MXPA98005953A - Benzymidazol nucleosides modified as antivira agents - Google Patents

Abstract

This invention pertains to nucleoside analogues which have antiviral activity and improved metabolic stability. More specifically, this invention pertains to modified sugar benzimidazole nucleosides, as exemplified by compounds such as benzimidazole nucleosides which possess a sugar-like, fluorinated portion (eg, a 2'-fluoro-furanosyl portion or a 3 'portion). -fluoro-furanosyl), and may be represented by the formula (I), wherein R1 is a portion similar to fluorinated sugar, and R2, R4, R5, R6 and R7 are benzimidazole substituents, such as -H, halogens (eg example, -F, -Cl, -Br, -l), -NO2, -NR2 (where R is independently -H or an alkyl group having 1-6 carbon atoms), -OR (where R is -H or a group alkyl having 1-6 carbon atoms), -SR (where R is -H or a hydrocarbyl of 1-10 carbon atoms), and -CF3. In one embodiment, R1 is 2'-fluoro-furanosyl or 3'-fluoro-furanosyl; R2 is -H, -F, -Cl, -Br, -l, or -NR2, wherein R is independently -H or a alkyl group having 1-6 carbon atoms, R 4, R 5, R 6 and R 7 are independently -H, -F, -Cl, -Br, or

Description

BENCIMIDAZO NUCLEOSIDES MODIFIED AS ANTIVIRAL AGENTS This application relates to a US serial application number 60 / 010,463 filed on January 23, 1996, the contents of which are incorporated herein by reference.

FIELD OF THE NONVENTION This invention pertains to nucleoside analogues which have antiviral activity and improved metabolic stability. More specifically, this invention pertains to modified benzimidazole nucleosides, as exemplified by compounds such as benzimidazole nucleosides possessing a fluorinated sugar-like portion (e.g., a 2'-fluoro-furanosyl portion or a 3'-fluoro portion). -furanosil).

BACKGROUND OF THE INVENTION Through this application, several publications, and published patent applications are referred by an identification appointment; Full citations for these documents can be found at the end of the specification immediately before the claims. The descriptions of publications, patents and published patent specifications referred to in this application are incorporated herein by reference in the present description to describe more complete way the state of the art to which this invention belongs. The benzimidazole nucleosides are particularly attractive as potential antiviral agents due to their ability to avoid some major routes of inactivation of bioactive (bicyclic) purine nucleoside, eg, adenosine deaminase deamination and glycosidic ligation cut by purine nucleoside phosphorylases. . For example, current therapy for HCMV includes the use of medications such as ganciclovir (also known as DHPG), foscarnet, and cidofovir. However, known benzimidazole nucleosides such as 5,6-dichloro-1- (β-D-ribofuranosyl) benzimidazole (DRB) have shown only marginal levels of activity or generally unacceptable levels of cytotoxicity or both, thereby greatly decreasing their utility in the treatment of viral infections. Recently, the benzimidazole compounds, such as TCRB (2,5,6-trichloro-1 - (2'-β-D-ribofuranosyl) benzimidazole) and 2-bromo-5,6-dichloro-1 - (2'- β-D-ribofuranosyl) benzimidazole (BDCRB) have been found to be useful against HCMV infections. See, for example, Townsend et al. , 1993, 1994, 1995. A number of benzimidazole nucleosides have been synthesized and tested for their antiviral activity and cytotoxicity in an effort to identify a compound with superior anti-human cytomegalovirus (HCMV) activity to ganciclovir and foscarnet. The antiviral activity of polysubstituted benzimidazoles such as 5,6-dichloro-1- (β-D-ribofuranosyl) benzimidazole (DRB) and some derivatives closely related have been previously described (Tamm, 1954). Its activity against specific viruses, such as RNA rhinovirus and herpes simplex virus type 1 and type 2 DNA, has also been reported. Several of the 5'-deoxyribosyl benzimidazole analogues, including 2,5,6-trichloro-1 (β-D-ribofuranosyl) benzimidazole (TCRB) have shown very potent activity against HCMV and low cellular toxicity at concentrations that inhibit viral growth . The structural activity relationships of TCRB and modified derivatives of carbohydrate and heterocycle have been reported. See, for example, Ravenkar et al. , 1968a. 1968b; Townsend et al. , March 1992; Zou er al. , 1992; Saluja et al. , 1992. These descriptions, however, do not describe the structure or synthesis of the compounds, which are the objective of this invention. Some modifications of the heterocycle have given analogs that are significantly more active than TCRB. However, most of these analogs are also more cytotoxic than TCRB, resulting in compounds with a slightly improved therapeutic index. Attempts to modify the carbohydrate portion by replacing the ribose with arabinose, xylose or acyclic analogues have given less active compounds than TCRB. Somewhat surprisingly a 5'-deoxy derivative of TCRB, 2,5,6-trichloro-1 (β-D-5'-deoxy-ribofuranosyl) benzimidazole was shown to be approximately 10 times more active than TCRB and to have a better therapeutic index than TCRB. Recent studies of the pharmacokinetics and metabolism of TCR B have revealed a drug half-life of approximately 0 6 hours in rats and 0.5-0.7 hours in monkeys (Good et al., 1994). The short life media may be associated with metabolic instability of the compound, for example, the cutting of the sugar portion of the benzimidazole.

I NDENTION COMPOUND An aspect of the present invention relates to modified benzimidazole nucleosides having a fluorinated sugar-like portion as described herein. In one embodiment, the fluorinated sugar-like portion comprises a 2'-fluoro-furanosyl portion or a 3'-fluoro-furanosyl portion. Another aspect of the present invention relates to pharmaceutical compositions for treating viral infections, which comprise a therapeutically effective amount of one or more of the modified benzimidazole nucleosides of the present invention, as described herein. Yet another aspect of the present invention corresponds to methods for treating viral infections in an animal patient comprising the step of administering a therapeutically effective amount of one or more of the modified benzimidazole nucleosides of the present invention, as described herein. Yet another aspect of the present invention pertains to methods for inhibiting viral proliferation (e.g., HCMV) in a virally infected cell comprising contacting the cell with an effective amount of one or more of the modified benzimidazole nucleosides of the present invention. , as described herein, under adequate conditions so that viral proliferation is inhibited. Yet another aspect of the present invention corresponds to methods of prophylactically treating a cell susceptible to viral infection (e.g., HCMV), by contacting the cell with an effective amount of one or more of the modified benzimidazole nucleosides of the present invention, as described herein, under suitable conditions so that viral infection is prevented. As will be apparent, the features and preferred features of one aspect of the invention are applicable to any other aspect of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a flow chart illustrating a method for the chemical synthesis of modified benzimidazole nucleosides having a portion similar to fluorinated sugar. Figure 2 is a flowchart illustrating another method for the chemical synthesis of modified benzimidazole nucleosides having a fluorinated sugar-like portion. Figure 3 is a flow chart illustrating yet another method for the chemical synthesis of modified benzimidazole nucleosides having a fluorinated sugar-like portion.

DESCRIPTION OF THE PREFERRED MODALITIES A. Antiviral Compounds of the Present Invention This invention pertains to modified benzimidazole nucleosides, which have antiviral activity and low toxicity and which offer improved metabolic stability, and therefore, longer half-lives in vivo. The compounds of the present invention can be described as "modified benzimidazole nucleosides", wherein the sugar-like portion in the 1-position (ie, R1) of a substituted benzimidazole has been derived, for example, to produce a similar portion. to fluorinated sugar. The compounds of the present invention can be represented by the formula: Where R1 is a portion similar to fluorinated sugar, and R2, R4, R5, R6 and R7 are benzimidazole substituents. Examples of benzimidazole substituents include -H, halogens (e.g., -F, -Cl, -Br, -I), -NO2. -N R2 (where R is independently -H or an alkyl group having 1-6 carbon atoms), -OR (where R is -H or an alkyl group having 1-6) carbon atoms), -SR (where R is -H or a hydrocarbyl of 1-10 carbon atoms), and -CF3. In one embodiment, the compounds of the present invention can be represented by the above formula, wherein R1 is a fluorinated sugar-like portion; R2 is -H, -F, -Cl, -Br, -I, or -NR2 (where R is independently -H or an alkyl group having 1-6 carbon atoms); and R4, R5, R6 and R7 are independently -H, -F, -Cl, -Br, or -I.

In one embodiment, the compounds of the present invention can be represented by the above formula, wherein R1 is a fluorinated sugar-like portion; R2 is -H, -F, -Cl, -Br, -I, or -NR2 (where R is independently -H or an alkyl group having 1-6 carbon atoms); Rs and R6 are independently -H, -F, -Cl, -Br, or -I; and R4 and R7 are -H. In another embodiment, the compounds of the present invention can be represented by the above formula, wherein R is a fluorine-like portion; R2, R5, and R6 are independently -H, -F, -Cl, -Br or -I; and R4 and R7 are -H. In another embodiment, the compounds of the present invention can be represented by the above formula, wherein R1 is a fluorine-like portion; R2 is N R2 (where R is independently -H or an alkyl group having 1-6 carbon atoms); R5, and R6 are independently -H, -F, -Cl, -Br or -I; and R4 and R7 are -H. In another embodiment, the compounds of the present invention can be represented by the above formula, wherein R1 is a portion similar to fluorinated sugar; R2, R5, and R6 are independently -H or -Cl; and R4 and R7 are -H. The term "sugar-like portion" as used herein refers to portions of monosaccharide. Preferred sugar-like portions are in cyclic form, for example, derivatives of furanose (5-membered ring) or pyranose (6-membered ring) forms, but more preferably of furanose forms. Examples of sugar-like portions include threo-furanosyl (from threo, a four-carbon sugar); erythro-furanosyl (from erythrose, a four-carbon sugar); ribo-furanosyl (from ribose, a five-carbon sugar); ara-furanosyl (also frequently referred to as arabino-furanosyl; arabinose, a five-carbon sugar); and xylo-furanosyl (from xylose, a five-carbon sugar). Examples of sugar-like portions having additional modi fi eons include derivatives of "deoxy", "keto", and "dehydro", for example 2'-deoxy-ribo-furanosyl; 3'-deoxy-ribo-furanosyl; 3'-keto-2'-deoxy-ribo-furanosyl; 2'-5'-dihydrofuran-2'-il; and 2 ', 3'-dihydrofuran-2'il. Sugar-like portions can be in any of their enantiomeric, diastereomeric or stereoisomeric forms, including for example, D or L forms. The modified benzimidazole nucleosides of the present invention can be in any stereochemical configuration, including, for example, or ß-anomeric. The term "fluorinated sugar-like portion" as used herein refers to sugar-like portions which have been derivatized to include at least one fluorine atom (i.e., -F). For example, furanosyl groups (5-membered ring) pentose derivatives (5 carbons) frequently have 2'-hydroxyl, 3'-hydroxy, and 5'-hydroxyl groups. The fluorinated derivatives of such sugar-like portions can be prepared, for example, by replacing one or more of the hydroxyl groups with fluoro groups. Examples of fluorinated sugar-like portions include 2'-fluoro-furanosyl and 3'-fluoro-furanosyl. Examples of preferred fluorinated sugar-like portions include 2'-fluoro-ara-furanosyl and 3'-fluoro-xylo-furanosyl. As used herein, the term "portion similar to fluorinated sugar" also encompasses portions similar to protected fluorinated sugar. For example, portions similar to fluorinated sugar, may possess one or more of the 2'-hydroxyl, 3'-hydroxyl, and / or 5'-hydroxyl groups in a protected form, for example, as an ester (eg, an acetate, -O (C = O) CH3), benzoate (i.e., -OC (= O) C6H5), or an ether (e.g., as a trityl ether, -OC (C6H5) 3). Throughout this application, the compounds described and claimed are identified by structure, name or by numerical designations.

The compounds of this invention include, but are not limited to, those examples shown below. 2,5,6-trichloro-1 - (2'-fluoro-ara-furanosyl) benzimidazole (wherein R 1 is 2'-fluoro-ara-furanosyl; R 2 is -Cl; R 4 is -H; Rs is -Cl; R6 is -Cl; and R7 is -H) (for example, compound 6); 2,5,6-trichloro-1 - (3'-fluoro-xylo-furanosyl) benzimidazole (wherein R 1 is 3'-fluoro-xylo-furanosyl; R2 is -Cl; R4 is -H; R5 is -Cl; R6 is -Cl; and R7 is -H) (for example, compound 7); 5,6-dichloro-1- (2'-fluoro-ribo-furanosyl) benzimidazole (wherein R 1 is 2, -fluoro-ribo-furanosyl; R 2 is -H; R 4 is -H; R 5 is -Cl; -Cl; and R7 is -H) (e.g., compound 15); 2-bromo-5,6-dichloro-1- (2'-fluoro-ribo-furanosyl) benzimidazole (wherein R 1 is 2'-fluoro-ribo-furanosyl; R 2 is -Br; R 4 is -H; Rs is - Cl; R6 is -Cl; and R7 is -H) (for example, compound 19); 2-isopropylamino-5,6-dichloro-1- (2'-fluoro-ribo-furanosyl) benzimidazole (wherein R 1 is 2'-fluoro-ribo-furanosyl; R 2 is -NH (CH (CH 3) 2); R 4 is -H; R5 is -Cl; R6 is -Cl; and R7 is -H) (for example, compound 20); The compounds of this invention are useful in the methods provided below or are useful as intermediates for the manufacture of other compounds of the present invention. It should be understood, although not always explicitly stated, that reference to any of the above compounds is to include pharmaceutically acceptable salts and operative combinations thereof.

B. Methods for using the antiviral compounds of the present invention As shown below, the compounds of this invention are potent antiviral drugs, and are particularly effective against HCMV and HSV-1, and as such, when combined with carriers, provide compositions for inhibiting viral reproduction and in vitro proliferation ex vivo or in vivo. For example, the compounds can be combined with various liquid phase carriers, such as sterile or aqueous solutions, pharmaceutically acceptable carriers as defined below.

The compounds of this invention can be combined with other antiviral drugs to provide an operative combination. The "operative combination" is intended to include any chemically compatible combination of a compound of this inventive group with other compounds of the inventive group or other compounds outside the inventive group (such as ganciclovir, AZT, and foscarnet), so long as the combination does not eliminate activity. antiviral of the compound of this inventive group. The compounds of the invention can be used to treat HCMV and HSV-1 infections in AI DS patients already receiving the antiviral drug zidovudine (AZT). Combination therapies with AZT may provide the advantage of less toxicity over the combination of ganciclovir with AZT. The combination of the compounds of this invention with AZT may produce less cytotoxicity (ie, antagonism) in cultured human cells than any agent used alone. In contrast, the combination of ganciclovir with AZT may produce greater cytotoxicity in human cells than the use of any of these drugs alone. This invention also provides a method for reducing or inhibiting the reproduction and proliferation of HCMV or HSV-1 in an infected HCMV or HSV-1 cell or cell population by contacting the cell or population with an effective amount of a compound of This invention and under suitable conditions, so that viral reproduction and proliferation is inhibited. One of skill in the art can easily determine when the reproduction and proliferation of HCMV or HSV-1 has been reduced or inhibited upon noticing a reduction in viral titer or an increase in the survival of the infected cells as compared to untreated infected cells. Viral titer assay methods are well known to those of skill in the art and are exemplified below. It should be readily understood that by inhibiting or reducing viral replication and proliferation, viral infectivity is also inhibited or reduced and cells are treated adequately for HCMV or HSV-1 infection. For the purposes of this invention, is intended to include a "cell", but not limited to a mammalian cell, for example, a mouse cell, a rat cell, a woodchuck cell, an ape cell, or a human cell. The viruses, which were treated by the compounds, compositions and methods of this invention, include DNA and RNA viruses, particularly herpes viruses. Examples of herpes viruses, or herpesviridae, are herpes simplex virus 1 (HSV-1), herpes simplex virus 2 (HSV-2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), human herpes virus 6 (HHV-6), human herpes virus 7 (HHV-7), and human herpes virus 8 (HHV-8). The compounds of the present invention are particularly useful in the treatment of HCMV and HSV-1 infections. Effective amounts are readily determined by those of skill in the art and will vary with the cell, viruses being effected and the purpose of the treatment. For example, when the drug is used in the culture of the cell, it is important that the amount of drug is not cytotoxic to the cells.

"Suitable conditions" include in vitro, ex vivo or in vivo. When the method is practiced in vitro, contact can be effected by incubating the cells with an effective antiviral amount of the compound, effective to inhibit viral reproduction and proliferation in the cell or cell culture. The compound can be added directly to the culture medium or combined with a carrier before the addition of the cells. In vitro, the method is particularly useful for inhibiting reproduction, viral proliferation and therefore infection in laboratory cell cultures. Ex vivo, the compounds are useful for inhibiting viral reproduction and proliferation in blood and plasma before being reintroduced into a patient. The use of compounds and in vitro methods also provides a powerful bioassay to classify novel drugs or compounds, which provide similar or enhanced antiviral activity. Using the methods set forth below, the medicament to be tested is assayed under the same conditions as a compound of this invention. The cytotoxicity and antiviral of the test drug can then be compared to a compound of this inventive group. Although the compounds are shown below to be particularly effective against HCMV and HSV-1, one skilled in the art can readily determine other viruses effectively treated with the compounds of this invention by using methods described herein and others. well known to those skilled in the art. Other viruses contemplated to be treated within the scope of the present invention include, but are not limited to: human immunodeficiency virus (HIV) and hepatitis virus. When the method is practiced in vivo in a subject such as a human patient, the compound can be added to a pharmaceutically acceptable carrier and systemically or topically administered to the subject, such as a human or mammalian patient such as a mouse, a rat , a marmot, or an ape. The compositions may also be administered to subjects or individuals susceptible to or at risk of a viral infection, such as HCMV or HSV-1 infection. Thus, this invention also provides a prophylactic method for inhibiting replication, viral proliferation and / or viral infection in a subject by administering to a subject a prophylactically effective amount of the compound or composition under suitable conditions such that replication, proliferation or viral infection it is inhibited. A "prophylactically effective amount" is an amount which inhibits viral infection, reproduction and proliferation in a subject challenged with the virus without toxicity to the cells and subject to being treated. It should be understood that by preventing or inhibiting proliferation, infection and viral replication in a subject or individual, the compositions and methods of this invention also provide methods for treating, preventing or ameliorating symptoms or disorders associated with viral infection, such as disease of inclusion, blindness, mononucleosis, restenosis (HCMV); chickenpox, herpes (varicella-zoster virus); infectious mononucleosis, glandular lymphoma, fever and Burkittis (Epstein-Barr virus); cold sores (herpes simplex virus 1); genital herpes (herpes virus) simple 2); roseóla infantum (human herpes virus 6, human herpes virus 7); Kaposi sarcoma (human herpes virus 8). Thus, this invention also provides methods for improving, preventing or treating disorders or symptoms associated with viral infection, for example. infection of HCMV or HSV-1, for example, restenosis, opportunistic infections (such as retinal infections, gastrointestinal infections, pneumonia, CNS infections) and in uterine infections, by administering to the subject an effective amount of a compound of this invention under adequate conditions so that the disorder or symptom is improved. prevented or treated. The in vivo administration can be carried out in a dose, continuously or intermittently throughout the course of treatment. Methods for determining the most effective means and dosage of administration are well known to those of skill in the art and will vary with the composition used for therapy, the target virus, the purpose of the therapy, the target cell being treated, and the subject being treated. Simple or multiple administrations can be performed with the dose level and standard being selected by the attending physician. Suitable dosage formulations and methods for administering the compounds can be found later. The fluorinated benzimidazole nucleosides of the present invention exhibit all antiviral activity against HCMV and HSV-1, many with acceptable cytotoxicity. It will be appreciated that the compounds of the present invention which exhibit relatively high antiviral activity against cytotoxicity, ie, good selectivity, are preferred. As well it will be appreciated that the antiviral treatment according to the present invention encompasses the treatment of viral infections, as well as prophylactic treatment, which may be desired in certain situations, for example in immunocompromised patients, such as transplant patients of organs and spinal cord, as well as patients who harbor HIV, who are particularly susceptible to HCMV or HSV-1 infection. The compounds and compositions of the present invention can be used in the manufacture of medicaments and in the antiviral treatment of humans and other animals by administration according to conventional procedures, such as an active ingredient in pharmaceutical compositions. The compounds of the invention can be provided as pharmaceutically acceptable formulations and / or "prodrugs", including but not limited to esters, especially carboxylic acid esters (preferably Ci to C20), such as 5'-acetyl and 2 'prodrugs, 3 ', 5'-triacetyl and pharmaceutical salts such as thiolate, citrate and acetate salts. The pharmaceutical compositions can be administered topically, orally, intranasally, parenterally or by inhalation therapy, and can take the form of tablets, pills, granules, capsules, pills, ampules, suppositories or aerosol form. They can also take the form of ointments, gels, pastes, creams, sprays, lotions, suspensions, solutions and emulsions of the active ingredient in aqueous or non-aqueous diluents, syrups, granules or powders. In addition to a compound of the present invention, the pharmaceutical compositions they may also contain other pharmaceutically active compounds or a plurality of compounds of the invention. More particularly, a compound of the formula of the present invention also referred to herein as the active ingredient, can be administered for therapy by any suitable route including oral, rectal, nasal, topical (including transdermal, aerosol, buccal or sublingual), vaginal, parental (including subcutaneous, intramuscular, intravenous and intradermal) and pulmonary. It will also be appreciated that the preferred route will vary with the condition and age of the recipient, the virus being treated and the nature of the infection. In general, a suitable dose for each of the above-mentioned viral infections, eg, HCMV and HSV-1, is in the range of about 0.1 to about 250 mg per kilogram of body weight of the receptor per day, preferably in the range of about 1 to about 100 mg per kilogram of body weight per day and most preferably in the range of about 5 to 20 mg per kilogram of body weight per day. Unless indicated otherwise, all active ingredient weights are calculated as the parent compound of the formula of the present invention for salts or esters thereof, the weights would be proportionally increased. The desired dose is preferably presented as two, three, four, five, six or more sub-doses administered at appropriate intervals throughout the day. These sub-doses may be administered in dosage unit forms, for example, containing about 10 to about 1000 mg, preferably about 20 to 500 mg, and most preferably about 100 to about 400 mg of active ingredient per unit dosage form. It will be appreciated that appropriate dosages of the compounds and compositions of the invention may depend on the type and severity of the viral infection and may vary from patient to patient. Determining the optimal dosage will generally involve balancing the level of therapeutic benefit against any risk or deleterious side effects of the antiviral treatments of the present invention. Ideally, the active ingredient should be administered to achieve peak plasma concentrations of the active compound from about 2 μM to about 100 μM, preferably about 5 μM to about 70 μM, most preferably about 1 to about 50 μM. This can be achieved for example, by intravenous injection of about 0.1 to about 5% solution of the active ingredient, optionally in saline, or administered orally, for example, as a tablet, capsule or syrup containing about 0.1 to about 250 mg per kilogram of the active ingredient. Desirable blood levels can be maintained by continuous infusion to provide about 0.01 to about 5.0 mg / kg / hour or by intermittent infusions containing about 0.4 to about 15 mg per kilogram of the active ingredient. The use of operational combinations is contemplated to provide therapeutic combinations that require a lower total dosage of each antiviral agent component that may be required when each compound or individual therapeutic medicine is used alone, thereby reducing adverse effects, for example, cytotoxicity. While it is possible for the active ingredient to be administered alone, it is preferred to present it as a pharmaceutical formulation comprising at least one active ingredient, as defined above, together with one or more pharmaceutically acceptable carriers therefor and optionally other therapeutic agents. Each carrier must be "acceptable" in the sense of being compatible with the other ingredients of the formulation and not harmful to the patient. Formulations include those suitable for oral, rectal, nasal, topical (including transdermal, buccal and sublingual), vaginal, parenteral (including subcutaneous, intramuscular, intravenous and intradermal) and pulmonary administration. The formulations can conveniently be presented in unit dosage form and can be prepared by any method well known in the pharmacy art. Such methods include the step of bringing the active ingredient into association with the carrier, which constitutes one or more accessory ingredients. In general, the formulations are prepared by uniformly and intimately bringing into association the active ingredient with liquid carriers or finely divided solid carriers or both, and then, if necessary, shaping the product. Formulations of the present invention suitable for oral administration can be presented as discrete units such as capsules, cachets or tablets, each containing an amount predetermined active ingredient; as a powder or granules; as a solution or suspension in an aqueous or non-aqueous liquid; or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion. The active ingredient can also be presented as a bolus, electuary or paste. A tablet can be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets can be prepared by compressing in a suitable machine the active ingredient in a free-flowing form such as a powder or granules, optionally mixed with a binder (eg, povidone, gelatin, hydroxypropylmethyl cellulose), lubricant, inert diluent, preservative , disintegrant (eg, sodium starch glycolate, cross-linked povidone, cross-linked sodium carboxymethyl cellulose) surface-active or dispersing agent. The molded tablets can be made by molding in a suitable machine, a mixture of the powdered compound moistened with an inert liquid diluent. The tablets may be optionally covered or labeled and may be formulated so as to provide controlled or slow release of the active ingredient therein using, for example, hydroxypropylmethyl cellulose in varying proportions to provide the desired release profile. The tablets may optionally be provided with an enteric coating. to provide release in parts of the intestine other than the stomach.

Formulations suitable for topical administration in the mouth include lozenges comprising the active ingredient in a flavored base, usually sucrose or gum arabic or tragacanth; pills comprising the active ingredient in an inert base such as gelatin and glycerin, or sucrose and arabic; and mouth rinses comprising the active ingredient in a suitable liquid carrier. The pharmaceutical compositions for topical administration according to the present invention can be formulated as an ointment, cream, suspension, lotion, powder, solution, paste, gel, spray, aerosol or oil. Alternatively, a formulation may comprise a patch or a bandage such as an adhesive bandage or patch impregnated with active ingredients and optionally one or more excipients or diluents. For infections of the eye or other external tissues, for example, mouth and skin, the formulations are preferably applied as a topical ointment or cream containing the active ingredient in an amount of, for example, about 0.075 to about 20% w / w, preferably about 0.2 to about 25% p / p and most preferably about 0.5 to about 10% w / w. When formulated in an ointment, the active ingredient can be used with either a paraffinic or water-miscible ointment base. Alternatively, the active ingredients can be formulated in a cream with an oil-in-water cream base. If desired, the aqueous phase of the cream base may include, for example, at least about 30% w / w of a polyhydric alcohol, i.e., an alcohol having two or more hydroxyl groups such as propylene glycol, butane-1 , 3-diol, mannitol, sorbitol, glyceroi and polyethylene glycol and mixtures thereof. Topical formulations may include Desirably a compound, which enhances the absorption or penetration of the active ingredient through the skin or other affected areas. Examples of such dermal penetration enhancers include dimethyl sulfoxide and related analogues. The oil phase of the emulsions of this invention can be constituted from known ingredients in a known manner. While this phase may simply comprise an emulsifier (otherwise known as an emulsifier), it conveniently comprises a mixture of at least one emulsifier with a fat or an oil or with both a fat and an oil. Preferably, a hydrophilic emulsifier is included together with a lipophilic emulsifier, which acts as a stabilizer. It is also preferred to include both an oil and a fat. Together, the emulsifier (s) with or without stabilizer (s) form the so-called emulsifying wax, and the wax together with the oil and / or fat form the so-called emulsifying ointment, which forms the oily dispersed phase of the emulsion formulations. cream. Emulsifiers and emulsion stabilizers suitable for use in the formulation of the present invention include Tween 60, Span 80. Cetostearyl alcohol, myristyl alcohol, glyceryl monostearate and sodium lauryl sulfate. The choice of oils or fats suitable for the formulation is based on achieving the desired cosmetic properties, since the solubility of the active compound in most of the oils likely to be used in pharmaceutical emulsion formulations is very low. Thus, the cream should preferably be a non-greasy, non-staining product and Washable with adequate consistency to avoid leakage of tubes or other containers. Mono- or dibasic, straight-chain or branched alkyl esters, such as di-isoadipate, isocetyl stearate, propylene glycol diester of coconut fatty acids, isopropyl myristate, decyl oleate, isopropyl palmitate, butyl stearate, palmitate 2-ethylhexyl or a mixture of branched chain esters known as Crodamol CAP can be used, the last three being the preferred esters. These can be used alone or in combination depending on the required properties. Alternatively, high-melting lipids such as white soft paraffin and / or liquid paraffin or other mineral oils can be used. Formulations suitable for topical administration to the eye also include eye drops, wherein the active ingredient is dissolved or suspended in a suitable carrier, especially an aqueous solvent for the active ingredient. The active ingredient is preferably present in such a formulation in a concentration of about 0.5 to about 20%, advantageously about 0.5 to about 105, particularly about 1.5% w / w. Formulations for rectal administration may be presented as a suppository with a suitable base comprising, for example, cocoa butter or a salicylate. Formulations suitable for vaginal administration may be presented as pessaries, tampons, creams, gels, pastes, foams or sprays containing, in addition to the ingredient active, such carriers as are known in the art to be appropriate. Formulations suitable for nasal administration, wherein the carrier is a solid, include a coarse powder having a particle size, for example, in the range of about 20 to about 500 microns, which is administered in the manner in which Aspiration is taken, that is, by rapid inhalation through the nasal passage of a powder container held near the nose. Suitable formulations wherein the carrier is a liquid for administration with, for example, nasal spray, nasal drops, or by spray delivery by nebulizer, include aqueous or oily solutions of the active ingredient. Formulations suitable for parenteral administration include sterile aqueous and non-aqueous isotonic injection solutions, which may contain anti-oxidants, buffers, bacteriostats and solutes, which render the formulation isotonic with the intended recipient's blood; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents, and liposomes or other microparticle systems which are designed to target the compound to blood components or one or more organs. The formulations can be presented in sealed multidose containers or dosage unit, for example, ampoules and flasks, and can be stored in a freeze-dried condition (lyophilized) requiring only the addition of the sterile liquid carrier, for example for injections, immediately before use. The solutions and Extemporaneous injection suspensions can be prepared from sterile powders, granules and tablets of the kind previously described. Preferred unit dosage formulations are those containing a daily dose or unit, daily sub-dose, as stated hereinbefore, or an appropriate fraction thereof, of an active ingredient. It should be understood that in addition to the ingredients particularly mentioned above, the formulations of this invention may include other agents conventional in the art with respect to the type of formulation in question, for example, those suitable for oral administration may include such additional agents as sweetening agents. , thickeners and flavorings. Compounds of the formula of the present invention may also be presented for use in the form of veterinary formulations, which may be prepared, for example, by methods that are conventional in the art.

C. Preparation of substituted sugar benzimidazoles modified General chemical procedures The melting points were taken on a Thomas-Hoover Unimelt apparatus and are not corrected. The nuclear magnetic resonance (NMR) spectra were obtained at 360 or 300 MHz with Bruker WP 360 SY or Bruker 300 SY. Elemental analyzes were performed by the Analytical Laboratory, Department of Chemistry, University of Michigan.

The spectra were made by the Mass Spectrum Laboratory of the Department of Chemistry, University of Michigan. Rapid column chromatography was performed using 230-400 mesh silica gel 60 (ICN) and the technique described by Still er al. (Still et al., 1978). Thin layer chromatography (TLC) was performed on pre-marked silica gel GHLF plates (Analtech, Newark, DE, USA). The compounds were visualized by illumination under UV light (254 nm) or by atomization with 20% methanolic sulfuric acid followed by scorching on a hot plate. Evaporations were carried out under reduced pressure (water aspirator) with water bath temperatures below 40 ° C unless otherwise specified. Fluorinated nucleosides have been commonly synthesized by any of two different routes. One route introduces the fluorine to a suitably protected nucleoside, while the other route condenses (eg, chemically or enzymatically) a heterocycle with a fluorinated sugar derivative. Amass of these strategies were investigated.

Benzimidazole Nucleoside Fluorination A method for the synthesis of a modified benzimidazole nucleoside is illustrated in Figure 1. In this method, a benzimidazole nucleoside, such as 2,5,6-trichloro-1-fluoosyl-benzimidazole was reacted with trityl chloride (ie, TrCI), dimethylaminopyridine (DMAP) and pyridine at 80 ° C for 4 hours. days to yield a mixture of 2 ', 5'-ditritylated and 3', 5'-ditritylated compounds. The compound 2 ', 5'- ditritylated was reacted with DAST (i.e., SF3Net2) in pyridine and dichloromethane (i.e., CH2Cl2), and subsequently reaction with trifluoroacetic acid (i.e., CF COOH) was made to produce the 3'-deoxy-3'- compound. f luoro, 2,5,6-trichloro-1 - (3'-deoxy-3'-fluoro-furanosyl) benzimidazole. In one embodiment, the compound is 2,5,6-trichloro-1- (3'-deoxy-3'-fluoro-β-xylo-furanosyl) benzimidazole, compound 7. Similarly, compound 3 ', 5' -ditritylated was reacted with DAST (ie, SF3Net2) in pyridine and dichloromethane (i.e., CH2Cl2), and subsequently reacted with trifluoroacetic acid (i.e., CF3COOH) to produce the compound 2'-deoxy-2'- fluoro, 2,5,6-trichloro-1 - (2'-deoxy-2'-fluoro-furanosyl) benzimidazole. In one embodiment, the compound is 2,5,6-trichloro-1- (2'-deoxy-2'-fluoro-β-ara-furanosyl) benzimidazole, compound 6. The glycosylation of various purines with 2'- derivatives Deoxy-2'-fluoro-arabinofuranosyl has been examined (Chu er al., 1989; Pankiewicz et al., 1992). Fluorination of a suitably protected derivative of compound 1 with dialkylamino sulfur trifluoride (DAST) was investigated, as described herein. While DAST has been reported to be an efficient fluorinating reagent for several nucleosides, it is well known that the conformation of the protected furanose portion is crucial to obtain the desired attack of the weakly nucleophilic fluoride on the β side (Krezeminski et al., 1991; Pankiewicz et al. , 1993). For a displacement of a group that leaves in the 2 'position, it is important that the furanose ring assumes an unfavorable conformation for trans- elimination. Such conformation can be induced by using bulky protective groups at C-5 'and C-3' (Theim et al., 1985). 2,5,6-trichloro-1 - (3,5-di-O-trityl-β-D-ribofuranosyl) benzimidazole (compound 2 was synthesized using reaction conditions similar to those described in the literature (Blank et al., 1970) Tritylation of compound 1 using TrCI and DMAP in pyridine at 80 ° C for 4 days gave a mixture of the ditrityl derivatives 2,5,6-trichloro-1 (3,5-di-O-trityl-β -D-ribofuranosyl) benzimidazole (Compound 2) and 2,5,6-trichloro-1 - (2,5, -di-O-trityl-β-D-ribofuranosyl) benzimidazole (compound 3) in a yield of 38% The attempts to improve performance by increasing the reaction time, reaction temperature or using bases other than DMAP to catalyze the reaction were not successful The di-O-trityl derivatives, compounds 2 and 3, could not be separated by flash column chromatography, but were separable by thin layer chromatography (EtOAc / hexane: 1: 2, three or four submersions) .These compounds were conveniently separated med. fractional crystallization from diethyl ether to give a ratio of 1: 3 of compounds 3 and 2. The justification for the assignment of compound 3 as the 2 ', 5'-di-O-trityl derivative and compound 2 as the 3 ', 5'-di-O-trityl derivative is based on homonuclear decoupling experiments. While the 3 ', 5'-di-O-trityl derivative, compound 2, was only obtained in 10% yield of compound 1, the isomeric derivative of 2', 5'-ditrityl, compound 3, was obtained in 30% yield Fluorination of compound 3 using DAST and pyridine in CH 2 Cl 2 yielded 2, 5,6- trichloro-1 - (2,5, -di-O-trityl-3-deoxy-3-fluoro-β-D-xylofuranosyl) benzimidazole (compound 5) in 71% yield. Fluorination of compound 2 using the same conditions gave 2,5,6-trichloro-1 (3,5-di-O-trityl-2-deoxy-2-fluoro-β-D-arabinofuranosyl) benzimidazole (compound 4) in a yield of 63%. Both compounds 4 and 5 were deprotected using 10% CF3COOH in CHCl3 to give good yields of the deprotected nucleosides 2,5,6-trichloro-1- (2-deoxy-2-fluoro-β-D-arabinofuranosyl) benzimidazole (compound 6) and 2,5,6-trichloro-1 - (3-deoxy-3-fluoro-β-D-xylofuranosyl) benzimidazole (compound 7), respectively. The fiuoro derivatives 6 and 7 are the β-arabino-furanosyl and β-xylo-furanosyl derivatives, respectively, since they were synthesized from the pre-formed β: ribofuranosyl nucleoside, compound 1, using DAST. These DAST fluorinations are known to replace a hydroxyl group with fluorine with a configuration inversion (Herdewijn et al., 1989). Additional support for the assignments of compounds 6 and 7 such as the ß-arabinofuranosyl and ß-xylofuranosyl derivatives, respectively. comes from the fact that both show a large coupling range between C7-H and F: this coupling is slightly higher for compound 6 (J = 1.9 Hz) than for compound 7 (J = 1.7 Hz). This indicates that the fluorine and the heterocycle are on the same side of the furanose ring. Finally, for the compound arabinose derivative 6, the coupling between the 1 '-H and the F is 17.7 Hz: this accumulation is an indicator of a trans neighborhood between 1 '-H and F (Wright et al., 1 969).

Compounds 2 and 3 2,556-trichloro-1 - (3,5-di-O-trityl-β-D-ribofuranosl) benzimidazole (2) and 2,5,6-trichloro-1 - (2) 5-di -O-trityl-β-D-ribofuranosyl) benzamidazole (3).

A mixture of compound 1 (5.0 g, 0.014 mol), DMAP (1.25 g, 0.014 mol) and TrCI (12.0 g, 0.043 mol) in dry pyridine (100 ml) was heated at 80 ° C for 3 days. Additional amounts of TrCI (12.0 g, 0.043 mol) were added on the 2nd and 3rd day. After 3 days the reaction was quenched with MeOH (60 ml). The reaction mixture was concentrated under reduced pressure and coevaporated with toluene (3 x 100 ml). The obtained residue was stirred in toluene (150 ml), filtered and the filtrate was evaporated to dryness. The resulting yellow foam was purified by flash chromatography (toluene 0.5 I, then toluene / EtOAc 20: 1, 5 cm x 20 cm) to give, after combining fractions containing ditrityl compounds and removal of the solvent under reduced pressure, a mixture of compounds 2 and 3 (4.5 g, 38%). Recrystallization from EtOEt mostly gave compound 3 while the filtrate was enriched in compound 2. Compound 3 could be purified in homogeneity by two additional recrystallizations from EtOEt to give 3.0 g (25%) of compound 3 as white crystals. Filtering which contained mostly compound 2, was evaporated to dryness and subsequently purified by recrystallization from EtOAc / hexane to give 1.0 g (8.4%) of pure compound 2 as white crystals. Compound 2: mp 174-175 ° C; Rf 0.19 (toluene / EtOAc 20: 1); Rf 0.62 (EtOAc / hexane 1: 2); 1 H-N M R (300 MHz, DMSO-d 6): d 8.06 (s, 1 H), 8.02 (s, 1H), 7.13-7.42 (m, 30 H, trifly), 6.24 (d, 1H, 2'-OH, J2., OH = 6.2 Hz), 6.18 (d, 1H, 1'-H, Jr, 2- = 8.3 Hz), 4.76 (m, 1H, 2'-H, becomes q in D2O wash with J, 2- = 7.9 Hz, J2., 3 '= 5.3 Hz), 4.23 (d, 1H, 3' -H, J2..3. = 5.4 Hz), 2.93 (m, 1H, 4'-H), 2.86 (dm, 1H, 5'-H), 2.64 (dm, 1H, 5'-H). Anal. Caled. For C5oH39Cl3N2O4: C, 71.65, H, 4.69, N, 3.34; found C, 71.50, H, 4.85, N, 3.24. Compound 3: mp 193-195 ° C; Rf 0.19 (toluene / EtOAc 20: 1); Rf 0.62 (EtOAc / hexane 1: 2); 1 H-NMR (300 MHz, DMSO-d 6): d 7.93 (s, 1H), 7.54 (s, 1H), 7.01-7.41 (m, 30 H, trityl), 6.22 (d, 1H, 1'-H, Jr, 2 = 8.4 Hz), 5.39 (d, 1H, 3'-OH, J3'-OH = 6.0 Hz), 4.50 (dd, 1H, 2'-H, J, r = 8.4 Hz, J2., 3 . = 4.4 Hz), 4.09 (m, 1H, 4'-H), 3.58 (t, 1H, 3'-H, J3 \ OH = 6.0 HZ, J2, 3 = 4.4 HZ: it becomes a pair in wash of D2O with J2., 3. = 4.4 Hz), 3.04 (dd, 1H, 5'-H), 3.18 (dd, 1H, 5'-H). Anal. Caled. For C50H39Cl3N2O4.1 / 2 H2O: C, 70.88, H, 4.76, H, 3.31; found C, 70.93, H, 4.80, N.3.31.

Compound 4 2,5,6-trichloro-1- (3,5-di-O-trityl-2-deoxy-2-fluoro-β-D-inofuranosyl) benzimidazole (4). The 3 ', 5'-di-O-trityl compound, compound 2 (0.3 g, 0.36 mmol) was dissolved in CH CI2 (10 mL). To this solution was added pyridine (0.3 ml, 3.6 mmol) and DAST (0.24 ml, 1.8 mmol) and the reaction was stirred at room temperature for 24 h. Additional CH2CI2 (200 ml) was added to the reaction mixture and the mixture was extracted with saturated NaHCO3 (100 ml) and washed with water (100 ml). The organic phase was dried over magnesium sulfate, filtered and the solvent was removed in vacuo. The resulting syrup was purified by chromatography Instantaneous (EtOAc / hexane 1: 2, 2 cm x 15 cm), fractions containing the product were extracted and the solvent was removed in vacuo to give, after recrystallization from EtOH, 0.20 g (67%) of compound 4 as a white solid. Compound 4: mp 145 ° C; Rf 0.57 (EtOAc / hexane 1: 2); 1H-NMR (360 MHz, CDCI3): d 7.65 (d, 1H, C7-H, J = 3.7 Hz, wide coupling range to F), 7.62 (s, 1H, C-4-H), 7.19-7.45 (m, 30 H , Tr), 6.10 (dd, 1H, 1'-H, Jr- Hz), 3.60 (dd, 1H, 2'-H, J2-, F = 50.3 Hz, Jr, 2 = 2.3 Hz), 3.50 (m, 1H, 5'-H), 3.27 (m, 1H, 5" -H) HRMS m / z caled, for C5oH38CI3FN2? 3 838.1932, found 838.1949, Anal.Called, for C50H38CI3FN2O3: C, 71.47, H, 4.56, N, 3.33, found C, 71.15, H, 4.72, N, 3.37 .

Compound 5 2J5,6-trichloro-1- (2,5-di-O-trityl-3-deoxy-3-fluoro-β-D-xylofuranosyl) benzimidazole (5). The 2 ', 5'-ditritrile compound, compound 3 (1.2 g, 1.44 mmol), was dissolved in CH2Cl2 (30 mL). To this solution was added pyridine (1.1 ml, 14.4 mmol) and DAST (1.0 ml, 7.2 mmol) and the reaction mixture was stirred at room temperature for 24 h. Additional CH2CI2 (200 ml) was added to the reaction mixture and the mixture was extracted with saturated NaHCO3 (100 ml) and washed with water (100 ml). The organic phase was then dried over magnesium sulfate, filtered and the solvent removed in vacuo. The resulting syrup was purified by flash chromatography (EtOAc / hexane 1: 2, 4 cm x 15 cm) and the product containing fractions were combined and the solvent was removed under reduced pressure to give, after recrystallization from EtOH, 0.85 g (70%) of compound 5 as a white solid. Compound 5: pf > 240 ° C (decomposes); Rf 0.6 (EtOAc / hexane 1: 2): 1 H-NMR (300 MHz, CDCl 3): d 7.73 (s, 1H), 7.17-7.40 (m, 31 H, C4-H and trifly), 6.17 (d, 1H , 1'-H, Jr, 2. = 4.5 Hz), 4.54 (dd, 1H, 2'-H, J, 2. = 4.5 Hz, J2., F = 20.9 Hz), 4.14 (dm, 1H, 4 '-H, J4-.F = 31.4 Hz), 3.99 (dd, 1H, 3'-H, J3., 4. = 2.1 Hz), 3.50 (m, 1H, 5'-H), 3.27 (m, 1H, 5'-H). HRMS m / z caled, for C5oH38CI3FN2? 3 838.1924, found 838.1957. Anal. Caled, for C5oH38CI3FN2O3 »1/2 H2O: C, 70.72, H, 4.63, N, 7.88; found C, 70.82, H, 4.77, N, 3.35.

Compound 6 2,5,6-trichloro-1- (2-deoxy-2-fluoro-β-D-inofuranosyl) benzimidazole (6). Compound 4 (0.10 g, 0.12 mmol) was dissolved in 10% CF3COOHal in CHCl3 (10 mL) and stirred at room temperature in a stoppered flask for 60 min. The reaction mixture was evaporated to dryness in vacuo, the oily residue was purified by flash chromatography (EtOAc / hexane 5: 1, 2 cm x 15 cm), the appropriate fractions were extracted, the solvent was removed in vacuo and the residue white crystallized from MeOH / H2O to give 25 mg (60%) of compound 6 as white crystals. Compound 6. Mp 223 ° C; Rf 0.43 (EtOAc / hexane 5: 1); 1H-NMR (360 MHz, DMSO-de): d 8.29 (d, 1H, C7-H, J = 1.9 Hz, wide range coupled to F), 7.93 (s, 1H, C4-H), 6.44 (dd, 1H, 1'- H, Jr, F = 17.7 Hz, Jr, 2 '= 4.5 Hz), 6.02 (d, 1H, 3'-OH, exchangeable D2O), 5.31-5.35 (m, 1.5 H, 5'-OH and 0.5 of 2'-H, 5'-OH D2O exchangeable) 5.25 (dm, 0.5 H, 2 '-H, J2-, F = 53.2 Hz, J2-.3- = 2.7 Hz), 4.42 (dm, 1H, 3'-H, becomes ddd in D2O wash with J3', F = 24.2 Hz, J2 -, 3- = 2.7 Hz and J3.?4.=5.9 Hz), 3.71-3.86 (m, 3H, 4'-H and 5'-H); 13 C-NMR (90 MHz, DMSO-dβ): d 140.81, 140.60, 134.07, 126.07, 125.68, 119.88, 115.61, 97.38 (2'C, J cF = 192.5 Hz), 84.98 (1'C, JrC? F = 17.4 Hz), 82.89 (4'C), 73.25 (3'C, J2.C? F = 24.4 Hz), 59.05 (5'C, J5'C, F = 9.9 Hz); HRMS m / z caled, for C? 2H10Cl3FN2O3 353.9741, found 353.9735. Anal. Caled for C 12 H 10 Cl 3 FN 2 O 3: C, 40.53, H, 2.83, N, 7.88; found C, 40.55, H, 2.94, N, 7.48.

Compound 7 2,5,6-trichloro-1- (3-deoxy-3-fluoro-β-D-xylo-furanosyl) benzimidazole (7). Compound 5 (0.28 g, 0.32 mmol) was dissolved in 10% CF3COOH in CHCl3 (20 ml) and stirred at room temperature in a stoppered flask for 45 min. The reaction mixture was evaporated to dryness in vacuo, the oily residue was purified by flash chromatography (EtOAc / hexane 5: 1, 2 cm x 15 cm), appropriate fractions were extracted, evaporated to dryness and crystallized from MeOH / H2O to give 85 mg (74%) of compound 7 as white crystals. Compound 7: mp 238 ° C; Rf 0.42 (EtOAc / hexane 5: 1); 1H-NMR (300 MHz, DMSO-d6): d 8.01 (s, 1H, C4-H), 7.93 (d, 1H, C7-H, J = 1.7 Hz, wide range coupled to F), 6.29 (d, 1H, 2'- OH, exchangeable D2O), 5.91 (d, 1H. 1'-H, Jr, 2. = 4.6 Hz), 5.17 (dd, 1H, 3'-H, J3.F = 52.8 Hz), 5.14 (t, 1H, 5'-OH, D2O exchangeable), 4.63 ( dm, 1H, 2'-H, J2-F = 22.6 Hz, becomes dd in wash D2O with J2-, F = 22.6 Hz and Jr, 2 = 4.6 Hz), 4.30 (dm, 1H, 4'-H, J4., F = 28.5 Hz), 3.69-3.84 (m, 2H, 5 ' -H); 13 C-NMR (90 MHz, DMSO-d 6): d 141.80, 140.94, 132.19, 125.967, 120.40, 113.61, 113.53, 96.90 (3'C, JVC, F = 184.1 Hz), 91.14 (1'C, Jrc, F = 4.6 Hz), 80.46 (4'C, J4.C, F = 19.8 HZ), 77.81 (2'C, J2-CF = 26.89 Hz), 57.71 (5'C, JS'C, F = 9.96); HRMS / m / z caled, for C 2 H 10 Cl 3 FN 2 O 3 353.9741, found 353.9747. Anal. Caled, for C? 2H10Cl3FN2O3: C, H, N. C12H10Cl3FN2O3: C, 40.53, H, 2.83, N, 7.88; found C, 40.77, H, 2.88, N, 7.56.

Coupling of a fluorinated sugar with a benzimidazole Another method for the synthesis of a modified benzimidazole nucleoside is illustrated in Figure 2. In this method, a fluorinated sugar-like compound is prepared and subsequently reacted with a benzimidazole to form the compound wanted. For example, a furanose which is 2'-, 3'-, and 5'-protected with benzoyl groups (ie, -OC (= O) C6H5) and 1'-protected with an acetate group (ie, -OC (= O) CH3) was converted to a 1'-deoxy-1'-bromo-2'-deoxy-2'-fluoro-3 ', 5'-benzoyl-furanose (see Howell et al., 1995) . This bromo-furanose was reacted with a benzimidazole, such as 2,5,6-trichlorobenzimidazole, in 1,2-dichloroethane (i.e., CICH2CH2CI) with 4 A sieve at 80 ° C for 2 days to yield a mixture of isomers of 2,5,6-trichloro- 1 - (2'-deoxy-2'-f-Ioro-3 ', 5'-benzoylifluorides i I) benzimidazole. Subsequent deprotection by reaction with ammonia (i.e., NH 3) in methanol (i.e., CH 3 H) afforded 2,5,6-trichloro-1- (2'-deoxy-2'-fluoro- furanosyl) benzimidazole. In one embodiment, the compound is 2,5,6-trichloro-1 - (2'-deoxy-2'-fluoro-β-ara-fu ranos il) benzimidazole (compound 6). The synthesis of 6 by coupling a fluorinated arabinofuranose compound (such as compounds 8 and 9) to a benzimidazole (such as 2,5,6-trichlorobenzimidaol, compound 6) was investigated. Initial attempts to use conditions of Vorbruggene attempts to glycosylate an alkaline salt of compound 6 were not successful. Compound 6 was successfully condensed with 1-bromo-3,5-di-O-2-deoxy-2-fluoro-aD-arabinofuranose (compound 9, Tann et al., 1985, Howell et al., 1988) using conditions similar to those described by Montgomery et al. (Montgomery et al., 1986). Thus, the condensation of compound 6 with compound 9 at 80 ° C in dichloroethane in the presence of molecular sieves of 4Á gave 2,5,6-trichloro-1- (3,5-di-O-benzoyl-2-) desired deoxy-2-fluoro-β-D-arabinofuranosyl) benzimidazole (compound 12 and its α-isomer (compound 1 1) The assignment of compound 12 as the β-anomer and the compound 1 1 as the α-anomer is based partially in its proton spectra The constant coupling between the fluorine and the 1'H is J, F = 23.1 Hz during compound 17 indicating a trans neighborhood relation of the proton to fluorine For compound 16 this constant coupling is JF = 17.4 Hz indicating a cis neighbor relation of the proton to the fluorine (Wright et al., 1969, Tann et al., 1985; Howell et al. 1,988; Reichman et al. , 1975). The additional justification for the anomeric assignment stems from the fact that C7-H at 7.91 ppm in compound 16 is separated by wide range of fluorine coupling (the signal is a pair, J = 3.2 Hz due to the coupling between C -H and F) which is not observed at C -H at 7.79 ppm for compound 17 (in this case the signal is a simple one). Further investigation of the condensation conditions showed that the anomeric ratio was highly dependent on the condensation conditions. The condensation conditions described above mostly gave the β-anomer, compound 17 (ratio / β: 1 / 5-1 / 10) in non-polar solvents such as dichloroethane and benzene. However, the α-anomer, compound 16 (ratio a / β 5/1 - 10/1) was the major product in more polar solvents such as acetonitrile and nitromethane. Yields were significantly better in nonpolar solvents such as dichloroethane (80% 8/1 ß / a) than in polar solvents such as acetonitrile (9% 1/7 ß / a). Deprotection of compound 1 2 in methanolic ammonia gave a compound identical to compound 6 previously characterized. Thus, an alternative route for the synthesis of compound 6 has been developed, which gave compound 6 in about 505 yield of the heterocycle (compound 6) and bromine sugar (compound 15), as compared to the 5% yield obtained using the previous method.

Compounds 1 1 and 1 2 2,5,6-trichloro-1 - (3,5-di-O-benzoyl-2-deoxy-2-fluoro-β-D-arabinofuranosyl) benzimidazole (12) and its α-isomer (eleven ). The 2-fluoro sugar, compound 8 (1.20 g, 2.6 mmol, Tann et al., 1985) was dissolved in CH2Cl2 (10 ml) and then 33% H Br in CH3COOH solution was added (2.64 ml, 10.4 mmol). The reaction mixture was stirred in a stoppered flask for 6 h. Additional CH2Cl2 (100 ml) was added to the reaction mixture and the organic phase was washed sequentially with ice-cold saturated NaHCO3 (100 ml) and ice water (100 ml). The CH2Cl2 solution was dried over magnesium sulfate, filtered and the solvent was removed under reduced pressure to give a colorless syrup of compound 9. This syrup was dissolved in CICH2CH2CI (10 ml) and added to a previously prepared solution containing 2 g. , 5,6-trichlorobenzimidazole, compound 10 (0.6 g, 2.6 mmol) in CICH2CH2CI (10 ml) and activated 4Á sieves. The resulting mixture was heated to 80.}. ° C under an inert atmosphere for 2 days. Then CH2Cl2 (100 mL) and a saturated NaHCO3 solution (100 mL) were added to the reaction mixture. The organic phase was separated and washed with water (100 ml), then dried over magnesium sulfate, filtered and the solvent removed in vacuo. The resulting solid was purified by flash chromatography (EtOAC / hexane: 1: 2, 4 cm x 15 cm) with the fractions containing the fastest moving nucleoside being extracted, concentrated to dryness and recrystallized from MeOH / H2O and then a from EtOH to give 0.12 g (8%) of compound 1 1 as white crystals. Fractions containing the slower moving nucleoside were contaminated with a small amount of compound 10. These contaminated fractions were extracted, concentrated to dryness and re-chromatographed on a second column (5% MeOH in C HCl3, 4 cm x 1 5 cm) to give after extracting the appropriate fractions and stirring solvent under reduced pressure a white solid, which after recrystallizations from MeOH / H2O gave 1.0 g (72%) of compound 12. Compound 11: mp 78-80 ° C; Rf 0.60 (EtOA / hexane 1: 2); Rf 0.9 (5% MeOH in CHCl3); 1 H-NMR (360 MHz, CDCl 3): d 8.12 and 8.00 (2m, 4H), 7.79 (s, 1H), 7.72 (s, 1H), 7.24-7.63 (m, 6H, benzoyl), 6.64 (dd, 1H , 1'-H, Jr, 2. = 3.9 Hz, J? F = 17.4 Hz), 5.82 (dd, 1H, 2'-H, J2-.F = 18.7 Hz, J2-, 3- = 1.90 Hz) , 5.63 (dm, 1H, 3'-H, J3, F = 49.3 Hz), 4.94 (m, 1H, 4'-H), 4.88 (dd, 1H, 5'-H), 4.67 (dd, 1H, 5'-H); HRMS m / z caled, for C26H18CI3FN2O5 562.0265, found 562.0276. Anal. Caled, for C 26 H 18 Cl 3 FN 2 O 5: C, 55.39, H, 3.22, N, 4.97; found C, 55.74, H 3.23, N 4.87. Compound 12: mp 88-90 ° C; Rf 0.36 (EtOA / hexane 1: 2); Rf 0.67 (5% MeOH in CHCl3); 1 H-NMR (360 MHz, CDCl 3): d 8.07-8.18 (m, 4H), 7.91 (d, 1H, C7-H, J = 3.2 Hz wide coupled range for F), 7.43-7.73 (m, 7H, benzoyl and C4-H), 6.40 (dd, 1H, 1'-H, Jr, 2 = 2.7 Hz, Jr.F = 23.1 Hz), 5.78 (dd, 1H, 3'-H, J3., F = 19.0 Hz , J3.4- = 3.8 Hz), 5.39 (dd, 1H, 2'-H, Jr, 2 '= 2.7 Hz, J, F = 50.3 Hz), 4.91 (m, 2H, 5'-H), 4.57 (q, 1H, 4'-H, J3, 4 = 3.6 Hz); HRMS m / z caled, for C26H? 8CI3FN2O5 562.0265, found 562.0254. Anal. Caled, for C26H1sCI3FN2? 5: C, 55.39, H, 3.22, N, 4.97; found C, 55.34, H 3.23, N 4.87.

Compound 6 2,5,6-trichloro-1- (2-deoxy-2-fluoro-β-D-arabinofuranosyl) benzimidazole (6). Compound 12 (0.5 g, 0.9 mmol) was dissolved in methanolic ammonia and the solution was stirred at room temperature. environment for 6 h. The solvent was removed in vacuo and the residue was purified by flash chromatography (EtOAc / hexane 5: 1, 2 cm x 15 cm), the appropriate fractions were extracted and evaporated to dryness to give after crystallization from MeOH, 0.23. g (74%) of a white solid identical to the compound 6 previously characterized. Yet another method for the synthesis of a modified benzimidazole nucleoside is illustrated in Figure 3. In this method, a uridine derivative comprising a fluorinated sugar-like portion is reacted with a benzimidazole in the presence of the N- transferase enzyme. deoxyribo-furanosyl to form the desired compound. The benzimidazole portion of this compound can be further derivatized, for example, in the 2-position to produce 2-substituted benzimidazole nucleosides (e.g., 2-Br, 2-N R2).

Compound 15 5,6-dichloro-1- (2-deoxy-2-fluoro-β-D-ribofuranosi I) benzidazole (15). 2'-deoxy-2'-fluoruridine, compound 13 (0.99 g, 4 mmol), which can be prepared by the method of Codington et al. (Codington et al., 1 968), was dissolved in 800 ml of 50 mM citrate buffer pH 6.0. 5,6-dichlorobenzimidazole, compound 14 (0.30 g, 1.6 mmol), which can be prepared by the method of Townsend et al. (Townsend et al., 1970) was added and the reaction was placed in a 50 ° C water bath. The N-deoxyribo-furanosyl transferase (60,000 units, see Cook et al., 1990) was added and the reaction mixture was stirred gently overnight. 5,6-dichlorobenzimidazole, compound 14 (0.30 g, 1.6 mmol) was added and the reaction continued for 2 days. The enzyme was precipitated by heating at 80 ° C followed by cooling to room temperature. Celite® (50-60 g) was added and the reaction mixture was filtered. The product was extracted with ethyl acetate (3X). The ethyl acetate was removed in vacuo and the residue was purified by chromatography on 75 g of basic alumina levigated with chloroform / methanol (95: 5, v / v) followed by (9: 1), v / v), then 2 : 1, v / v), and finally (1: 1, v / v). Fractions containing product were combined and the solvents were removed in vacuo to give 0.54 g (67%) of compound 15. Compound 15: MS (FAB +) m / z, 321, M + 1. 1H-NMR (DMSO-d6) d 8. 62 (s, 1H, H-2), 8.19 (s, 1H, Ar-H), 7.96 (s, 1H, Ar-H), 6.35 (dd, 1H, H-1 ', Jr, 2. = 3.5 Hz, J, F = 14.9 Hz), 5.74 (br s, 1H, OH), 5.23 (dt, 1H, H-2 \ Jr, 2. = 3.5 Hz, J2.3. = 4.4 Hz, J2., F = 52.4 Hz), 5.23 (br s, 1H, OH), 4.35 (dt, 1H, H-3 \ J2.3. = 4.4 Hz, J3., 4- = 5.3 Hz, J3-.F = 15.9 Hz) , 3.98 (m, 1H, H-4 '), 3.66 (dd, 2H, H-5', J = 3.4 Hz, J = 12.5 Hz).

Compound 16 5,6-dichloro-1- (2-deoxy-2-fluoro-3,5-diacetyl-β-D-ribofuranosyl) benzimidazole (16). Compound 15 (0.45 g, 1.4 mmol) was dissolved in pyridine (20 ml) and boiled to remove the water. The solution was cooled to 0 ° C in an ice bath. Acetic anhydride (260 μl, 29 mmol, 2 equiv.) Was added and the reaction mixture was allowed to warm to room temperature while stirring overnight. Methanol (3 ml) was added and the solvents were removed in vacuo. The residual pyridine was removed by coevaporation with toluene (3X).

The residue was partitioned between water and ethyl acetate. The ethyl acetate solution was dried with magnesium sulfate, filtered and the solvent removed in vacuo to yield 0.56 g (98%) of compound 16. The product was used without further purification. Compound 16: MS (FAB +) m / z, 405, M + 1. 1 H NMR (DMSO-d6) d 8.59 (s, 1 H, H-2), 8.05 (s, 1 H, Ar-H), 8.01 (s, 1 H, Ar-H), 6.45 (dd) , 1 H, J-1", Jr.2- = 4.8 Hz, Jr.F = 14.8 Hz), 5.75 (dt, 1 H H-2 \ J = 5.2 Hz, J2, F = 51 Hz), 5.40 ( m, 1 H, H-3 '), 4.43 (m, 1 H, H-4'), 4.28 (m, 2 H, H-5 '), 2.1 3 (s, 3 H, acetyl-CH 3), 2.02 ( s, 3H, acetyl-CH 3).

Compound 1 7, 18, and 19 2-bromo-5,6-dichloro-1 - (2-deoxy-2-fluoro-3,5-diaceti l-β-D-ribofuranosii) benzim idazole (1), 2- bromo-5,6-dichloro-1 - (2-deoxy-2-fluoro-5-d-acetyl-β-D-ribofuranosyl) benzimidazole (18), and 2-bromo-5,6-dichloro-1 - (2-deoxy-2-fluoro-β-D-ribofuranosyl) benzimidazole (19). Compound 16 (0.55 g, 1.4 mmol) was dissolved in dioxane (25 ml) and boiled to remove the water. The solution was heated to reflux in an oil bath at 120 ° C. N-bromosuccinimide (N BS, 0.48 g, 2.8 mmol 2 equiv.) Was added and the reaction mixture was refluxed for 4 min. A second portion of NMS (0.48 g, 2.8 mmol, 3 equiv.) Was added and the reflux continued for 6 min. The reaction mixture was removed from the heat, diluted with chloroform (40 ml) and cooled to room temperature. The solution was washed with saturated sodium bicarbonate (2X), dried with magnesium sulfate and filtered. The solvents were removed in vacuo, and the residue was purified by chromatography on 75 g of gel. silica levigated with ethyl acetate / hexane (1: 1, v / v). The fractions containing product were combined and the solvents were removed in vacuo to give compound 17. The hydrolysis of the acetyl groups was achieved by treatment in methanol and ethanol (17 ml each) with sodium carbonate (0.22 g, 2.1 mmol, 2 equiv.) Dissolved in 4.2 ml of water. The reaction mixture was stirred at room temperature overnight. The solution was diluted with water (40 ml). The products were extracted with ethyl acetate (2X). The ethyl acetate solution was dried with magnesium sulfate, filtered and the solvent removed in vacuo. The residue was purified by chromatography on 75 g of silica gel eluted with ethyl acetate / hexane (1: 4, v / v) followed by (1: 2, v / v). The fastest levigating product was the 5'-acetyl compound, compound 18 (0.17 g) and the second product to levigate was the dihydroxy compound. compound 19 (0.03 g). Compound 18: MS (Fab +) m7z, 399, M + 1. ? -NMR (DMSO-d6) d 8. 46 (s, 1H, Ar-H), 7.95 (s, 1H, Ar-H), 6.22 (dd, 1H, H-1 \ Jr.2- = 5.4 Hz, Jr.F = 14.5 Hz), 5.82 ( d, 1H, OH-3 ', J = 5.6 Hz), 5.45 (t, 1H, OH-5', J = 4.5 Hz). 5.29 (dt, 1H, H-2 \ J = 5.2 Hz, J2-, F = 53 Hz), 4.3 (m, 1H, H-3 '), 4.0 (m, 1H, H-4'), 3.7 ( m, 2H, H-5 '). Compound 19: 1 H-NMR (DMSO-d 6) d 8.00 (s, 1H, Ar-H), 7.90 (s, 1H.

Ar-H), 6.258dd, 1H, H-1 ', Jr, 2 = 5.1 Hz, Jr.F = 16.5 Hz), 5.95 (d, 1H, OH-3. "J = 6 Hz), 5.40 (dt , 1H, H-2 ', J = 5.3 Hz, J2-.F = 53 Hz), 4.4-4.1 (m, 4H, H-3 \ 4". 5'), 2.13 (s, 3H, CH3-acetyl ).

Compound 20 2-isopylamino-5,6-dichloro-1- (2-deoxy-2-fluoro-β-D-ribofuranosyl) benzimidazole (20). Compound 18 (0.06 g, 0.14 mmol) was dissolved in ethanol (4 ml) and isopropylamine (1.3 ml) was added. The reaction mixture was heated in an oil bath at 90 ° C sealed for 17 h. The solvents were removed in vacuo and the residue was purified by chromatography on silica gel (6 g) eluted with chloroform / methanol (95: 5 v / v). The fractions containing product were combined and the solvents were removed in vacuo to give compound 20 (0.03 g, 57%). Compound 20: MS (APCH +) m / z, 378, M + 1. 1H-NMR (DMSO-d6) d7.66 (s, 1H, H-2), 7.37 (s, 1H, Ar-H), 6.92 (d, 1H, NH J = 7.7 Hz), 6.17 (dd, 1H, H-1", Jr, 2 = 5.3 Hz, Jr, F = 15.4 Hz), 5.73 (d, 1H, OH-3 ', J = 5.7 Hz), 5.63 (t, 1H, OH-5 ', J = 4.3 Hz), 5.12 (dt, 1H, H-2', J = 5.3 Hz, J, F = 53 Hz), 4.29 (dt , 1H, J-3 '), 4.02 (m, 1H, CH), 3.94 (m, 1H, J-4'), 3.68 (m, 2H, H-5 '), 1.16 (d, 6H, CH3, J = 6.5 Hz).

D. assays for antiviral activity and cytotoxicity Cells and viruses KB cells (available from American Type Culture Collection (ATCC) 12301 Parklawn Drive, Rockport, MD 20852 (ATCC CCL 17)), an established human cell line derived from an oral epidermal carcinoma, were grown in minimal essential medium (MEM) (Sigma) with Hanks salts (MEM (H)) supplemented with 5% fetal calf serum. Human prepuce fibroblasts (HFF cells) were grown (provided by University of Michigan Hospital) and African green monkey kidney cells (BSC-1) (ATTC CCL 26) in MEM and Earl's salts (MEM (E)) supplemented with 10% fetal bovine serum. The cells were incubated according to conventional procedures and as described in Shipman et al., (Shipman et al., 1976). Briefly, cells were incubated in 1: 2 to 1: 10 dilutions according to conventional procedures using 0.05% trypsin plus 0.02% EDTA in a buffered HES EPES solution, HFF H cells were incubated only in dilutions 1 :2. A purified plate isolate, PQ, of the Towne species of HCMV was used in all experiments and was a gift from Dr. Mark Stinski, University of Iowa. The KOS species of HSV-1 was used and was provided by Dr. Sandra K. Weller, University of Connecticut. The HCMV and HSV-1 stock preparations were prepared and titrated as is known to those of skill in the art and is described in Turk et al. (Turk er al., 1987) and Shipman er al. (Shipman et al., 1990). Briefly, high-titer HSV-1 stocks were prepared as follows. Closely confluent monolayer cultures of KB cells were grown in 1 L glass bottles containing MEM (E) buffered with 25 mM H EPES and supplemented with 5% fetal bovine serum and 0.127 g / L L-arginine ( VGM, virus growth medium). The cultures were infected at a low input multiplicity to reduce the formation of defective viruses. After the cell cytopathology reached "three to four more", the cells were collected by vigorous agitation, and concentrated by centrifugation (800 x g for 5 min). The resulting virus deposits were stored at -76 ° C until they were recovered for use in experiments. HSV-1 was titrated using monolayer cultures of BSC-1 cells. Cells were plated at 3 x 10 5 cells / well using 6-well cluster dishes. MEM (E) supplemented with 105 fetal bovine serum was used as medium. After 22-24 h, the cells were 90% confluent and inoculated in triplicate using at least three ten-fold dilutions with 0.2 ml of the virus suspension to be tested and incubated in an atmosphere of 4% CO 2 - 90% Humidified air for one hour to allow viral adsorption. Following virus adsorption, the cell sheet was covered with 5 ml of MEM (E) with 5% serum plus 0.5% methocel (4000 CPS) and incubated for two to three additional days. The cells were fixed and stained with 0.1% crystal violet in 20% methanol and the macroscopic plates were enumerated. Reserve HCMV was prepared by infecting HFF cells at a multiplicity of infection (m.o. i.) Of less than 0.01 plaque forming units (p.f.u) per cell. The cell growth medium was changed every four days until the cytopathology was evident in all cells (approximately 21 days). The supernatant fluids were retained as the virus stock. Four days later, the remaining cells were disrupted by three freeze-thaw cycles and the cell plus the medium were sustained as an additional source of virus. The storage was in liquid nitrogen.

HCMV was titled in 24-well cluster dishes, which were platinized to contain 5 x 104 FF H cells / cavity, grown as described above. When the cells were 70 to 80% confluent, 0.2 ml of the virus suspension was added per cavity and adsorbed as described above. At least three ten-fold dilutions of each preparation were used. Following the adsorption of the virus, the leaves of cells were covered with 0.5% methocel (4000 CPS) in maintenance medium [MEM (E) with 1.1 g / liter of NaHCO3, 100 units / ml of penicillin G, 100 μg. / ml of streptomycin, and 5% of fetal bovine serum]. The cultures were incubated in a humidified atmosphere of 4% CO2- 96% air. Viral plaques were visible 5 to 7 days after infection using at least 10-fold magnification. The cells were fixed and stained by a 10 minute exposure to a 0.1% solution of crystal violet in 20% methanol 7 to 12 days after infection. Microscopic locations were enumerated at 20 times magnification using a Nikon Profile Projector.

Assays for antiviral activity HCMV plate and yield reduction experiments were performed with monolayer cultures of FF H cells by a method similar to that referred to above for virus titration and described in Townsend et al. (Townsend et al., 1995). The activity of the compounds against HSV-1 was evaluated using an ELISA assay, also described in Townsend et al. (Townsend er al., 1995).

The effect of HCMV replication compounds was measured using plaque reduction and yield tests. For the first, the HFF cells in 24-well culture dishes were infected with approximately 50 p.f.u. of HCMV per cavity using the procedures detailed above. The compounds dissolved in growth medium were added in four to six selected concentrations to cavities in duplicate following the adsorption of the virus. Following incubation at 37 ° C for 7 to 10 days, the leaves of cells were fixed, stained and the microscopic plates were enumerated as described above. The effects of the drug were calculated as a percentage of the reduction in the number of plaques in the presence of each drug concentration compared to the number observed in the absence of the drug. DH PG (ganciclovir) was used as a positive control in all experiments. Performance reduction trials were conducted as described in Townsend et al. (Townsend I went to., nineteen ninety five) . The ELISA techniques as described in Townsend et al. (Townsend et al., 1995) were used to determine activity against HSV-1. The drug effects were calculated as a percentage of the reduction in virus titers in the presence of each drug concentration compared to the titre obtained in the absence of medication. Acyclovir was used as a positive control in all experiments.

Cytotoxicity assays Two different methods were used to evaluate the cytotoxicity of the compounds. First, the cytotoxicity produced in stationary FF H cells was determined by microscopic examination of cells not affected by the virus used in the plaque assay. Second, the effect of the compounds on KB cells during two bending times of the population was determined by crystal violet staining and spectrophotometric quantification of levigated dye from stained cells. This method has been used for the analysis of ganciclovir and zidovudine (See Prichard et al., 1991). The cytotoxicity and antiviral activity data for two of the fluorinated sugar benzimidazole nucleosides of the present invention are presented in Table 1, together with comparison data for known antiviral agents TCRB and ganciclovir.

The cytotoxicity and antiviral activity data for three of the fluorinated sugar benzimidazole nucleosides of the present invention are presented below in Table 2. The HCMV AD169 species was grown in monolayers of human embryonic lung cells (MRC5 cells) in plates of 96 cavities. After injection of the cells at a rate of approximately 0.01 infectious virus particles per cell, the compounds to be tested were added to select cavities in six different concentrations, each in triplicate. The same concentrations of compounds were also applied to cavities containing monolayers of uninfected cells in order to assess the cytotoxicity of the compound. The plates were incubated for 5 days, and the minimum cytotoxic dose was estimated from the microscopic examination. The IC5o for antiviral effect was estimated from measurements of HCMV DNA in each cavity by blotting and quantitative specific DNA hybridization, similar to the Gadler method (see, Gadler, 1983). Briefly, the probe for hybridization was prepared from cosmids pC7531 and pCS37 (see, Suilivan et al, 1993). These contain the sequences HCMV AD169 of nucleotides 102,000 to 143,300 and 51,600 to 92,900, respectively. The probe is a 1: 1 mixture of the two cosmids labeled with α- [32 P] -dCTP using random primers and T7 DNA polymerase (Pharmacia) after cutting with Xba1 nuclease. The probe was denatured by heating for 2 minutes at 99 ° C and filtered through a sterile Corning filter of 0.45 μm (25933-200). The prehybridization of the membranes was performed in 6X SSPE (SSPE: 0. 18 M NaCl, 10 mM NaPO 4 (pH 7.7), 1 mM EDTA), 1% Ficoll. 1% polyvinylpyrrolidine, 1% BSA, 0.5% SDS, and 50 μg / ml salmon sperm DNA at 45 ° C for 2 to 12 h. The prehybridization solution was replaced with hybridization solution (6X SSPE, 0.5% SDS, 50 μg / ml salmon sperm DNA) containing 1 x 106 cpm / ml of each heat denatured probe. Hybridization was for 16 h at 65 ° C. The membranes were then washed as follows: 6X SSPE with 0.5% SDS, room temperature, 2X for 2 min; 1 X SSPE with 0.5% SDS, 65 ° C, 2X for 1 5 min; 0.1 X SSPE with 0.5% SDS, 65 ° C, once for 1 h.

The membranes were stained dry and wrapped in Saran wrapper for quantification by Phospholmager (Molecular Dynamics, Sunnyvale, CA). Phospholmager screens were exposed to spots for 16 to 24 h. The global accounts in each sample were calculated using ImageQuant computer program (Molecular Dynamics, Sunnyvale, CA) and net accounts obtained by subtracting the local membrane backup. The accounts of the drug dilution cavities were compared with the untreated control cavity accounts to produce a response curve and were used to calculate the IC 50 values. The ICS0 values were calculated by linear regression assigned according to the Hill equation.

The embodiments of this invention illustrated above are intended to aid in the understanding of the invention but are not intended, and should not be construed by, to limit the invention in any way as it is intended. set forth in the following claims. Other aspects, advantages and modifications within the scope of this invention will be apparent to those skilled in the art to which this invention pertains.

E. References Descriptions of publications, patents, and published patent specifications referred to below are incorporated herein by reference in the present description to more fully describe the state of the art to which this invention pertains.

Blank, H.U .; Frahne, D .; Myles, A .; Pfleiderer, W. Uber die Tritylierung von Adenosin-Derivate. Liebigs Ann. Chem. 1970, 747, 34-42.

Chu, C.K .; Matulic-Adamic, J .; Huang, J.-T .; Chou, T-C; BurchenaL J.H .; Fox, J.J .; Watanabe, K.A., "Nucleosides 135. Synthesis of some 9- (2-deoxy-2-fluoro-β-D-arabinofurnosyl) -9H-purines and Their Biological Activities," Chem. Pharm. Bull. 1989, 37, 336. Codington, J.F., Doerr, II. L., Fox, J.J., J. Org. Chem., 1964, vol. 29. pp. 558. Cook et al., J. Biol. Chem., (1990), Vol.265, p.2682. Devivar, R.V. et al. (1994) J. Med. Chem. Vol. 37: 2942-2949. Gadler, Antimicrob. Agents Chemother., 1983, vol.24, pp.370-374.

Good, et al., Antiviral Research (Suppl. 1), Vol.23, p. 103 (1994). Herdewijn, P .; Aerchot, A .; Kerremans, L. Synthesis of Nucleosides Fluorinated in the Sugar Moiety. The Application of Diethylaminosulfur Trifluoride to the Synthesis of Fluorinated Nucleosides. Nucleosides and Nucleotides 1989, 8, 65-96 and references therein. Howell I went to. , J. Org. Chem., 1995, Vol. 50, p. 3644-3647. Howell, H.G.; Bordfuehrer, P. R.; Brundige, S. P.; Benigne, D.A.; Sapino, C. Antiviral Nucleosides. A Steroeospecific, Total Synthesis of 2'-Fluoro-2'-deoxy-ß-D-arabinofuranosyl Nucleosides. J. Org. Chem. 1988, 53, 85-88. Krezeminski, J.; Nawrot, B.; Pankiewicz, K. W.; Watanabe, K.A. Synthesis of 9- (2-deoxy-2-fluoro-β-D-arabinofuranosyl) hypoxanthine. The First Direct Introduction of a 2'-ß-fluoro Substituent in Preformed Purine Nucleosides. Studies Directed Toward The Synthesis of 2'-Deoxy-2'-substituted Arabinonucleosides. Nucleosides and Nucleotides 1991, 19, 781-798. Montgomery, J.A.; Shortnacy, A.T.; Carson, D.A.; Secrist I I I, J .A. 9- (2-deoxy-2-fluoro-β-D-arabinofuranosyl) guanine: A Metabolically Stable Cytotoxic Analogue of 2'-deoxyguanosine. J. Med. Chem 1986, 29, 2389-2392. Pankiewicz, K. W.; Krzeminski, J.; Ciszewski, L.A.; Ren, W.Y. : Watanabe, KA, "A Synthesis of 9- (2-Deoxy-2-fluoro-ß-D-arabinofuranosyl) adenine and Hypoxanthine. An Effect of C3'-Endo to C2'- Endo Conformational Shift on the Reaction Course of 2 ' -Hydroxyl Group with DAST ", J. Org. Chem. 1992, 57 553-559. Pankiewicz, K.W.; Watanabe, K.A. A Synthesis of 2'-Fluoro- and 3'-Fluoro-Substituted Purine Nucleosides via Direct Approach. In Nucleosides as Antitumor and Antiviral Agents; Chu, C.K .; Baker, D.C., Eds .; Plenum Press: New York, 1993, pp. 55-71. Prichard, M.N. et al. Antiviral Res. (1991) Vol.35: 1060-1065. Reichman, U .; Watanabe, K.A .; Fox, J.J. A Practical Synthesis of 2-Deoxy-2-Fluoro-D-Arabinofuranose Derivatives. Carbohydr. Res. 1975, 42, 233-240 Revenkar, R.G. and Townsend, L.B. (1968) J. Heterocyclic Chem. Vol. 5: 477-483 Revenkar, R.G. and Townsend, L.B. (1968) J. Heterocyclic Chem. Vol. 5: 615-620; Saluja, S. et a. "Synthesis and antiviral activity of certain 2-substituted-5,6-dichlorobenzimidazole acyclic nucleosides Poster # 146, Division of Medicinal Chemistry, 204th American Chemical Society National Meeting, Washinton, DC, August 23-28, 1992. Shipman, C, Jr. et al. (1976) Antimicrob Agents Chemother, Vol. 9: 120 Shipman C, Jr., ei al (1990) J. Virol. Methods Vol.28: 101-106. Still, W.C .; Kahn, M .; Mitra, A., "Rapid Chromatographic Techniques for Preparative Separation with Moderate Resolution," J. Org. Chem. 1978, 43, 2923-2925. Tamm, I., Science (9154) Vol. 120: 847-848). Tann, C.H .; Brodfuehrer, P.R .; Brundige, S.P .; Sapino, C; Howell, H.G. Fluorocarbohydrates in Synthesis. An efficient Synthesis of 1- (2-Deoxy-2-fluoro-ß-D-arabinofuranosyl) -5-iodouracil (ß-FIAU) and 1- (2-Deoxy-2- fluoro-ß-D-arabinofuranosyl) thymine (ß-FMAU). J. Org. Chem. 1985, 50, 3644-3647. Thiem, J .; Rash, D. Synthesis and Perkow Reaction of Uridine Derivatives, Nucleosides and Nucleotides 1985, 4, 487. Townsend and Revankar, Chem. Rev., (970), Vol.70, p.389. Townsend, L.B. and Drach, J.C., fifth International Conference on Antiviral Research Vancouver, British Columbia, March 1992; Townsend, L.B., et al., J. Med. Chem., Vol. 38, pp. 4098-4105 (1995). Townsend, L.B. e. al., U.S. Patent No. 5,248, 672 issued September 28, 1993. Townsend, L.B. ei al., U.S. Patent No. 5,360, 795 issued November 1, 1994. Turk, S.R. i went to (1987) Antimicrob. Agents Chemother. Vol. 31: 544-550. V. Sullivan, K.K. Biron, C.L. Talarico, S.C. Stanat, M.G. Davis, L.S. Pozzi, and D.M. Coen, Antimicrob. Agents Chemother, 1993, vol. 37, pp. 19-25. Wright, J.A .; Taylor, N.F .; Fox, J.J. Nucleosides. LX. Fluorocarbohydrates. XXII. Synthesis of 2-deoxy-2-fluoro-D-arabinose and 9- (2-deoxy-2-fluoro-a- and β-arabinofuranosyl) adenines. J. Org. Chem. 1969, 34, 2632-2636. Zou, R. et al., "Design, synthesis and antiviral evaluation of some TCRB analogs modified on the benzene moiety," Poster # 142. Division of Medicinal Chemistry, 204th American Chemical Society National Meeting, Washington, D.C. , August 23-28, 1992.

Claims (10)

1. CLAIMS 1 . A modified benzimidazole nucleoside of the formula: wherein R1 is a portion similar to fluorinated sugar; R2 is -H, -F, -Cl, -Br, -I, or -NR2, wherein R is independently -H or an alkyl group having 1 - . 1-6 carbon atoms; R4 is -H, -F, -Cl, -Br, or -I; R5 is -H, -F, -Cl, -Br, or -I; R6 is -H, -F, -Cl, -Br, or -I; R7 is -H, -F, -Cl, -Br, or -I; and the pharmaceutically acceptable salts thereof. 2. The modified benzimidazole nucleoside of claim 1, wherein said fluorinated sugar-like portion comprises a portion of 2'-fluoro-furanosyl or a 3'-fluoro-furanosyl portion. 3. The modified benzimidazole nucleoside of claim 2, wherein said fluorinated sugar-like portion comprises a portion selected from the group consisting of: 2'-fluoro-threo-furanosyl; 3'-fluoro-threo-furanosyl; 2'-fluoro-erythro-furanosyl; 3'-fluoro-erythro-furanosyl; 2'-fluori-ribo-furanosyl; 3'-fluoro-ribo-furanosyl; 2'-fluoro-ara-furanosyl; 3'-fluoro-ara-furanosyl; 2'-fluoro-ara-furanosyl; 3'-fluoro-ara-furanosyl; 2'-fluoro-xylo-furanosyl; and 3'-fluoro-xylo-furanosyl. The modified benzimidazole nucleoside of claim 3, wherein said fluorinated sugar-like portion comprises a portion selected from the group consisting of: 2'-fluoro-ribofuranosyl; 2'-fluoro-ara-furanosyl; and 2'-fluoro-xylo-furanosyl. 5. The modified benzimidazole nucleoside of claim 4, wherein said fluorinated sugar-like portion possesses one or more hydroxyl groups in a protected form. 6. The modified benzimidazole nucleoside of claim 1, wherein R1 is 2-fluoro-ara-furanosyl; R2 is -Cl; R4 is -H; R5 is -Cl; R6 is -Cl; and R7 is -H. 7. The modified benzimidazole nucleoside of claim 1, wherein R1 is 2-fluoro-xylo-furanosyl; R2 is -Cl; R4 is -H; R5 is -Cl; R6 is -Cl; and R7 is -H. 8. The modified benzimidazole nucleoside of claim 1, wherein R1 is 2-fluoro-ribo-furanosyl; R2 is -H; R4 is -H; Rs is -Cl, R6 is -Cl; and R7 is -H. 9. The modified benzimidazole nucleoside of claim 1, wherein R 1 is 2-fluoro-ribo-furanosyl; R2 is -Br; R4 is -H; Rs is -Ci; R6 is -Cl; and R7 is -H. 10. The modified benzimidazole nucleoside of claim 1, wherein R1 is 2-fluoro-ribo-furanosyl; R2 is -NH (CH (CH3) 2); R4 is -H; R5 is -Cl; R6 is -Cl; and R7 is -H. eleven . A composition comprising a compound according to any of claims 1 to 10 and a pharmaceutically acceptable carrier. 12. The use of a compound according to any of claims 1 to 10, alone or in combination, for the preparation of a medicament for inhibiting or preventing viral infection. 13. A method for inhibiting viral proliferation in a virally infected cell comprising contacting the cell with an effective amount of a compound according to any of claims 1 to 10 under suitable conditions so that viral proliferation is inhibited. A method for inhibiting HCMV proliferation in an HCMV infected cell comprising contacting the cell with an effective amount of a compound according to any of claims 1 to 10 under suitable conditions so that the proliferation of HCMV is inhibited . 15. A method for prophylactically treating a cell susceptible to viral infection by contacting the cell with an effective amount of a compound according to any of claims 1 to 10 under suitable conditions such that the viral infection is inhibited. 16. A method for prophylactically treating a cell susceptible to HCMV infection by contacting the cell with an effective amount of a compound according to any of claims 1 to 10 under suitable conditions such that HCMV infection is inhibited.