US3560620A - Induction of fibrinolysis - Google Patents

Abstract

METHOD FOR INDUCING BIBRINOLYSIS IN MAMMALS, AND PHARMACEUTICAL COMPOSITIONS USEFUL THEREFOR, BY THE ACTION OF SPECIFIED ALKYLENEBIS (1,2,3,4-TERRAHYDROISOQUINOLINE) COMPOUNDS OR PHARMACEUTICALLY ACCEPTABLE ACID ADDITION SALTS THEREOF.

Description

United States Patent Office 3,560,620 Patented Feb. 2, 1971 3,560,620 INDUCTION F FIBRINOLYSIS Joseph M. Schor, Locust Valley, and Nathan Weiner, Rego Park, N.Y., assignors to Endo Laboratories Inc. No Drawing. Filed Aug. 9, 1966, Ser. No. 571,195

Int. Cl. A61k 27/00 US. Cl. 424-258 16 Claims ABSTRACT OF THE DISCLOSURE Method for inducing fibrinolysis in mammals, and pharmaceutical compositions useful therefor, by the action of specified alkylenebis [l,2,3,4-tetrahydroisoquinoline] compounds or pharmaceutically acceptable acid addition salts thereof.

This invention relates to means for inducing fibrinolytic activity in mammals. More particularly, it is directed to effecting high, sustained, useful levels of fibrinolytic activity in mammals by the action of alkylenebis [1,2,3,4-tetrohydroisoquinoline] compounds of the following Formula A, or pharmaceutically acceptable acid addition salts thereof, and to compositions containing such substances Formula A wherein:

The term pharmaceutically acceptable addition salt includes such salts as: the mineral acid salts, e.g., the hydrochloride, hydrobromide, sulfate and phosphate; and organic acid salts such as the succinate, benzoate, acetate, p-toluene-sulfonate and benzenesulfonate, and others formed from acids conventionally used in the pharmaceutical art.

In the formation of a blood clot, for example, athrombus, fibrinogen, a soluble plasma protein, is converted to the insoluble protein fibrin. As the fibrin is deposited it entraps blood cells within its meshwork to form a coagulum. In the case of a thrombus, the coagulum usually interferes with the flow of blood through the vessel.

The defense of the living organism against such occurrence is the plasma protein called plasminogen which, under certain conditions, can be activated by an activator whereby the plasminogen is converted to the protein, plasmin. Plasmin possesses the property of efficiently digesting and destroying fibrin (fibrinolysis). The fibrinolysis results in dissolution of the clot; and in the case of a thrombus, restores the potency of the vessel.

Under normal conditions, the organism has low levels of acitvator in the blood stream. It is believed that small amounts of plasminogen are constantly undergoing conversion to plasmin by the action of the activator. However, from a quantitative viewpoint the amount of activator normally present is insuflicient to produce enough plasmin to lyse the relatively large amount of fibrin present in a clot such as a thrombus.

The compounds of foregoing Formula A have the property of stimulating the production and/or release of relatively large quantities of activator activity into the blood stream. In essence, those compounds induce increased levels of activator which, in turn, produce high levels of plasmin within the clot and this results in dissolution thereof.

Consequently, the compounds of Formula A can be used to dissolve fibrin wherever it is deposited in the organism, independent of the cause of such deposition.

Fibrinolytic activity in vitro is manifested by many compounds such as the aromatic sulfonic acids, derivatives of salicyclic acid, long chain fatty acids and halogenated unsaturated acids. The compounds of the present invention, more importantly, are active in vivo.

Fibrinolytic activity in vivo can be induced by nicotinic acid, procaine, phenylbutazone, acetylcholine, epinephrine, serotonin and histamine. However, the effect of these compounds is of short-lived duration, i.e., of the order of minutes. The compounds of Formula A, in contrast thereto, can induce prolonged fibrinolytic activity, i.e., of the order of hours.

Some sulphonylureas and steroids can induce an increase in fibrinolytic activity, but a lag period of the order of hours precedes the slow increase in lyti cactivity. Compounds of this type cannot be used when a substance is employed to effect thrombolytic therapy, because in such instance the activity must be rapidly induced to be effectice in dissolving clots. The compounds of Formula A, in contrast thereto, are highly effective for such use because they induce maximal lytic activity within minutes after administration.

Streptokinase, a streptococcal protein, has been used for thrombolysis, but the side effects of pyrogenicity and anaphylactic reactions have limited its use. In contrast thereto, compounds of Formula A are free of these side reactions.

Urokinase, a protein isolated from human urine, has also been used for thrombolysis but the difficulties involved in accumulating large supplies of the starting material, human urine, and the great cost of preparing the substance have proscribed its general and practical utility.

Bacterial pyrogens have also been used to effect thrombolysis, but the severity and unpredictability of the pyrogenic reactions have negated their usefulness. The compounds of Formula A are not pyrogenic.

In short, the fibrinolytic compounds of Formula A are the first synthetic substances which demonstrate activity in mammals in vivo, are highly potent, long-lasting, rapid in onset, readily prepared and suffer from none of the difiiculties associated with materials of natural origin.

The compounds of Formula A may be used to effect fibrinolysis of the clot in acute thrombosis. They may also be employed prophylactically to maintain increased fibrinolytic activity or a long term basis and thus diminish the icidence of new thrombotic episodes.

The alkylenebis [1,2,3,4-tetrahydroisoquinoline] compounds and their acid addition salts present in the compositions of the invention, when used in accordance with this invention, possess a high degree of activity and consequently only small amounts are required to produce fibrinolytic effects in mammals. At these dose levels, side effects are generally negligible.

When substituents R and R in Formula A include hydroxy moieties, moderate to marked blood pressure lowering effects accompany the production of good fibrinolytic action.

Oxygenated functions are generally beneficial for maximum fibrinolytic activity and with one preferred aspect of this invention there is included in R and R one or more lower alkoxy functions such as methoxy, isopropoxy, butoxy or methylenedioxy. These functions are most effective when situated at the 6 and 7 positions of the tetrahydroisoquinoline ring systems.

The alkylene chain, designated as alk, may vary within wide limits with retention of fibrinolytic potency. Activity is maximized, however, when the tetrahydroisoquinoline rings are separated by chains of from three to ten carbon atoms. Examples of such chains are 2-propyltrimethylene, tetramethylene, 1,8-diethyloctamethylene and decamethylene.

The groups R R R and R in preferred compounds, represent hydrogen or alkyl groups of not more than four carbon atoms. Most preferred are those compounds in which R R R and R are hydrogen or methyl.

The compounds of Formula A are all either known or, in view of their structures, are readily prepared by methods frequently described in the literature. Generally speaking, their preparation comprises the interaction of an appropriately substituted phenylethylamine with a dicarboxyalkane, whereof the bridge between the carboxyl moieties corresponds to the length of the alkylene chain desired. The bis-phenylethylamide thus derived is then cyclized through dehydration to an alkylene-bis-[3,4-dihydroisoquinoline]. The latter is then converted into a compound of Formula A through reduction to the corresponding alkylenebis l,2,3,4-tetrahydroisoquinoline].

It will be apparent from a consideration of the synthetic processes involved in making these compounds that they are capable of occurring in isomeric forms. In the simplest instances, i.e., where R R R and R of Formula A represent hydrogen, there are d1 and meso diastereoisomers. When additional asymmetric centers are introduced the situation becomes more complex and more diastereoisomers are possible.

We have studied the fibrinolytic potencies of various diastereoisomers as well as the potencies of the diastereoisomeric mixtures from which they were derived. In each case the pure compounds and the mixtures were found to be useful fibrinolytic agents. Formula A therefore embraces all of the isomers arising during the synthesis of these compounds. It is intended that the designation of the compounds of Formula A, by names and by formulas throughout the specification and claims, shall be read to include all isomers and mixtures thereof unless otherwise specified.

An outstanding feature of the compounds of Formula A is their relative lack of toxicity. Although they are active at very low dose levels, it is possible to exceed minimum effective levels by wide margins without encountering serious adverse reactions. This permits the compounds to be used without concern about undesirable side effects, as are so frequently encountered upon inadvertent overdosage of other substances of great potency. For example, by intraperitoneal administration to rats, compounds of Formula A were found to be effective in inducing fibrinolysis at 0.05 mg./kg. It was found, indeed, that the same compounds could be administered at levels of 100 mg./kg. By intravenous administration to rats, the compounds were effective at 0.05 ing/kg. and also at 80 mg./kg. They were active by the oral route in rats at doses of from 5 to 300 mg./kg. In dogs they were active by intraveneous administration at 0.5 mg./kg. and also at 60 mg./kg. In humans they may be administered parenterally in doses of from 0.1 mg./kg. to 50 ing/kg. These dose levels are illustrative and are not meant to limit the application of the invention. The veterinarian or physician may find it advisable to adjust dosage in t light of individual recipient response.

The compositions of the invention contain an alkylenebis-[1,2,3,4-tetrahydroisoquinoline] having Formula A or a non-toxic acid addition salt thereof together with a carrier. The carrier may be either a solid or liquid and the compositions can be in the form of tablets, liquidfilled capsules, dry filled capsules, dragees, pills, aqueous solutions, non-aqueous solutions, jellies, suppositories, syrups, suspensions, sprays, powders and the like. The compositions can, and in many cases, do contain suitable preservatives, coloring and flavoring agents. Some examples of the carriers which can be used in the preparation of the products of the invention are gelatin capsules, sugars such as lactose and sucrose; cellulose, methyl cellulose and cellulose acetate phthalate; gelatin; talc; magnesium stearate; vegetable oils such as peanut oil, cottonseed oil, sesame oil, olive oil, corn oil and oil of theobroma; liquid petrolatum, polyethylene glycol; glycerine; sorbitol; propylene glycol; ethanol; agar; water and isotonic saline.

In preparing the compositions of the invention for pharmaceutical uses, the conventional practices and precautions are used. The compositions intended for parenteral administration must be sterile and this can be accomplished either by using sterile ingredients and carrying out the production under asceptic conditions or by sterilizing the final composition by one of the usual procedures such as millipore filitration. Customary care should be exercised that no incompatible condition exists between the active component and the diulent preservative or flavoring agent or in the conditions employed in preparation of the compositions.

The compositions of the invention can be introduced into the mammal by the oral, rectal, or parenteral route. This can be done by injecting the liquid preparations intraveneously, intramuscularly, intraperitoneally, or subcutaneously; by swallowing, in the cases of the solid and liquid preparations, by local application to the mucous membrances, in the case of jellies, suppositories, tablets and the like; by inhalation of sprays or mists of the liquid preparations and the like.

For a fuller understanding of the nature and objects of this invention, reference may be had to the following examples which are given merely as further illustrations of the invention and are not to be construed in a limiting sense. The temperatures are in degrees centigrade.

EXAMPLE 1 1, l '-tetramethylenebis[ l,2,3,4-tetrahydroisoquinoline] dihydrochloride A mixture of 35.2 g. of adipic acid di(2-phenylethyl) amide, M.P. 184l85, and 176 g. of polyphosphoric acid was heated at 190193 for 1.25 hours. After cooling to the mixture was poured onto ice along with 20 ml. of concentrated hydrochloric acid. After washing with chloroform and benzene, the aqueous layer was made strongly alkaline with aqueous sodium hydroxide, extracted with benzene, and the benzene solution washed with water, dried, and purified by passage through an alumina column. The residue of l,l-tetramethylenebis- [3,4-dihydroisoquinoline] remaining on evaporation of the benzene melted at 100-102 after recrystallization from hexane-ethyl acetate.

To a solution of 44.2 g. of the 3,4-dihydro compound in 500 ml. of ethanol, 21.2 g. of sodium borohydride was added in portions with stirring. After the exothermic reaction had abated, the mixture was refluxed for 3 hours, and then evaporated to dryness in vacuo. The residue was taken up in water, extracted with chloroform, and the extract dried and evaporated to dryness. The resulting oil was dissolved in absolute ethanol and treated with hydrogen chloride and ether. The solid product, representing an isomeric mixture of hydrochlorides, melted at 335- 338 (dec.). Fractional crystallization yielded one isomer (1.1) (A), M.P. 344-346 (decomposition) from water, and the second isomeric product (B) (1.2), M.P. 266- 269 from ethanol.

EXAMPLE 2 1,1-hexamethylenebis 1,2,3,4-tetrahydroisoquinoline] dihydrochloride A mixture of 38 g. of suberic acid di-(Z-phenylethyl) amide, M.P. 165-166, and 300 g. of polyphosphoric acid was heated at 240 for 1.5 hours. After cooling to 100- it was poured into 500 ml. of ice water containing ml. of concentrated hydrochloric acid. After washing with benzene, the aqueous phase was made basic and extracted several times with benzene. Concentration product 1,1- hexamethylenebis[3,4-dihydroisoquinoline], M.P. 9092 after recrystallization from acetonitrile.

A 30 g. sample of the bisdihydro compound was dissolved in ethanol and 13 g. of sodium borohydride was added with stirring. After 10 minutes at room temperature the mixture was heated under reflux for 1.5 hours. The ethanol was removed, water was added and the aqueous mixture was extracted with chloroform. The chloroform solution was dried and evaporated. The oily residue was taken up in ethanol, treated with hydrogen chloride and cooled in ice. The resulting isomer mixture of hydrochlorides melted at 275-285. Fractional crystallization yielded one isomer (A) (2.1), M.P. 291-294 from methanolethyl acetate and the second isomeric product (B) (2.2), M.P. 246-248 from ethanol.

EXAMPLE 3 -1,1'-hexamethylenebis[7-chloro-1,2,3,4-tetrahydroisoquinoline] dihydrochloride By the procedude of Example 2, suberic acid di[2-(4- chloropheny1)ethyl] amide was converted into the mixture of isomeric (3.1) bis[7-chlorotetrahydroisoquinoline] dihydrochlorides.

EXAMPLE 4 1,1'-hexamethylenebis[7-chloro-1,2,3,4-tetrahydroisoquinoline] dihydrochloride A mixture of 8.24 g. of adipic acid di[2-(3-methoxyphenyl)ethy1] amide, M.P. 152, ml. of phosphorus oxychloride, and 82 ml. of dry toluene was refluxed for 0.5 hour. After cooling in ice, the precipitate was filtered and washed with benzene and acetone. A solution of this solid in warm water was made strongly alkaline with aqueous sodium hydroxide, and the product extracted into chloroform, washed with water and dried. Removal of the solvent gave 1,1'-tetramethylenebis[3,4-dihydro- 6-methoxyisoquino1ine], M.P. 105106 after recrystallization from cyclohexane. Reduction with sodium borohydride as described in Example 1, followed by treatment with hydrogen chloride yielded the mixture of 11 and meso isomeric products, (4.1) M.P. 272-273".

EXAMPLE 5 1,1'-tetramethylenebis 1,2,3,4-tetrahydro-6,7-methy1enedioxyisoquinoline] A mixture of 43 g. of adipic acid di[2-(3,4-methylenedioxyphenyl)ethyl] amide, M.P. 207208, and 130 ml. of phosphorus oxychloride was heated under reflux for one hour. Excess phosphorus oxychloride was removed under reduced pressure and the residue was treated with water and then with alkali and chloroform. The chloroform was concentrated and the crystalline residue was recrystallized from toluene to yield 1,l-tetramethylenebis [3,4-dihydro-6,7-methylenedioxyisoquinoline], M.P. 214- 215.

The dihydro compound (17 g.) was dissolved in hot dioxane (2 liters) and treated dropwise with 6.4 g. of sodium borohydride in 200 ml. of ethanol. After the exothermic reaction subsided, the mixture was heated under reflux for an additional 3 hours and concentrated. The mixture of diasterioisomers (5.1) melted at 175-190.

6 EXAMPLE 6 1,1'-tetramethylenebis [7-benzyloxy-1,2,3,4-tetrahydro-6- methoxy-isoquinoline] dihydrobromide A mixture of 6.53 g. of adipic acid di-[2-(4-benzyloxy-3-methoxyphenyl)ethyl] amide, M.P. 197, 20 ml. of phosphorus oxychloride, and 65 m1. of dry toluene was refluxed for 1 hour. After cooling the precipitate was washed with benzene and acetone. A solution of the precipitate in hot water was made strongly alkaline with aqueous sodium hydroxide, and, after cooling in ice, the precipitate was filtered and washed with water. Recrystallization from absolute ethanol gave 1,l-tetramethylenebis[7 benzyloxy 3,4 dihydro-6-methoxyisoquinoline], M.P. 166. Reduction thereof with sodium borohydride as described in Example 1, followed by treatment with hydrogen bromide yielded the mixture of (11 and meso isomer hydrobromides (6.1).

The following products are prepared in similar fashion:

(6.2) 1,1'-tetramethylenebis[7 allyloxy 1,2,3,4-tetra hydro-6-methoxyisoquinoline] (6.3) 1,1-tetramethylenebis[1,2,3,4 tetrahydro 6- methoxy-7-phenoxyisoquinoline] EXAMPLE 7 1,1'-tetramethylenebis[1,2,3,4-tetrahydro-7-hydr0xy- 6-methoxyisoquinoline] Reduction of 1,1-tetramethylenebis[7-benzyloxy-3,4-dihydro-6-methoxyisoquinoline] described in Example 6, with 10% palladium on charcoal and hydrogen in acetic acid resulted in debenzylation to produce the mixture of isomeric 7-hydroxy compounds, (7.1) M.P. 259-261".

EXAMPLE 8 1,1'-tetramethylenebis-[6-benzyloxy-7-butoxy-1,2,3,4- tetrahydroisoquinoline] dihydro chloride 2-(3-benzyloxy 4 butoxyphenyl)-N-acetylethylamine was hydrolyzed with dilute sodium hydroxide and the resulting amine was converted into the desired product (8.1) by the procedures of Example 6.

EXAMPLE 9 1,1'-(2-propyltrimethylene) 1,2,3,4-tetrahydroisoquinoline) 1,2,3,4-tetrahydro-6,7-dimethoxyisoquinoline) 3-(3,4-dihydro 6,7 dimethoxy-l-isoquinolylmethyl)- hexanoic acid and 2-phenylethylamine were heated at 200 to produce the amide. Cyclization with phosphorus oxychloride followed by reduction with sodium borohydride as described in Example 1 yielded the product.

EXAMPLE 1O 1,1'-tetramethylenebis[1,2,3,4-tetrahydro-6,7,8-trimethoxyisoquinoline] dihydrochloride A mixture of 19.0 g. of adipic acid di-[2-(3,4,5-trimethoxyphenyDethyl]amide, M.P. 174-175 57 ml. of phosphorus oxychloride, and ml. of dry toluene was refluxed for 0.5 hour to give an oil which solidified on cooling. The solid was filtered, washed with benzene and acetone, and then dissolved in hot water and made strongly 7 EXAMPLE 11 Ingredients: Mg. tablet 1,1' hexamethylenebis[l,2,3,4 tetraisoquinoline]dihydrochloride,isomerA 25 Lactose USP (spray dried) 170 Starch USP Magnesium stearate USP 1 Stearic acid USP 5 Flavor Q.s.

All the above ingredients were passed through 60 mesh sieve, blended for 30 minutes and compressed directly into tablets on a suitable press at a weight of 211 mg. using a biconcave, scored punch.

'EXAMPLE 12 Ingredients: Mg./Capsule 1,1-hexamethylenebis[ 1,2,3,4-tetramethylene- 6,7-dihydroxyisoquinoline] dihydrobromide Lactose USP 100 Magnesium stearate 1 Cab-O-Sil (amorphous silicon dioxide) 5 These ingredients were combined, blended and passed through a No. 1 screen of Fitzpatrick comminutor machine before encapsulating into a two piece hard gelatin No. 3 capsule on a standard capsulating machine at a net weight of 126 mg.

EXAMPLE 13 Ingredients: Ampoule l,1-tetramethylenebis[1,2,3 ,4-tetrahydro-6,7- dimethoxyisoquinoline] dihydrochloride, isomer B mg Pyrogen free water for injection ml 25 Mannitol N.F. To make the solution isotonic.

The compound is added to the water and the solution made isotonic with mannitol. The resulting pH is 5.5. The

solution is filled into ampoules under sterile conditions and the sealed ampoule is autoclaved. The ampoule contains 5 ml. of the 5 mg./ml. solution.

EXAMPLE 14 Ingredients: Ampoule l,1'-hexamethylenebis[1,2,3 ,4-tetrahydro-6,7

dimethoxy-3-methylisoquinoline] dihydrochloride mg 25 Pyrogen free water for injection ml 25 Dextrose N.F. To make the solution isotonic.

The compound is added to the water and the solution made isotonic with dextrose. The resulting pH is 5.5. The solution is filled into ampoules under sterile conditions and the sealed ampoule is autoclaved. The ampoule contains 5 ml. of the 5 mg./ml. solution.

EXAMPLE 15 Ingredients: Ampoule 1,1 -decamethylenebis 1,2,3 ,4-tetrahydro-6,7- dimethoxyisoquinoline] dihydrochloride dihydrate mg 25 Pyrogen free water for injection ml 25 Fructose N.F. To make the solution isotonic.

The compound is added to the water and the solution made isotonic with fructose. The resulting pH is 5 .5 The solution is filled into ampoules under sterile conditions and the sealed ampoule is autoclaved. The ampoule contains 5 ml. of the 5 mg./ml. solution.

EXAMPLE 16 Ingredients: Per ampoule 1,1-tetramethylenebis[1,2,3,4-tetrahydro-6- methoxyisoquinoline] mg 25 Peanut oil ml 5 Benzyl alcohol mg 5 The compound is dissolved in the peanut oil containing the benzyl alcohol. The ampoules are filled under sterile conditions. Each ampoule contains 5 ml. of 5 mg. of the compound/ml.

EXAMPLE 17 Ingredients: Mg,/suppository 1,l-hexamethylenebis[7-chloro-1,2,3,4-tetrahydroisoquinoline] 200 Cocoa butter c- Q.s.

The compound and cocoa butter are combined, mixed thoroughly and formed into two gram suppositories.

EXAMPLE 18 Ingredients Mg./ suppository 1,1'-hexamethylenebis[1,2,3 ,4-tetrahydroisoquinoline], isomer B 200 Oil of theobroma Q.s.

The compound and oil of theobroma are combined, mixed thoroughly and formed into two gram suppositories.

EXAMPLE 19 Ingredients: Grams/liter 1,1-hexamethylenebis[1,2,3 ,4-tetrahydro-6,7-

dimethoxyisoquinoline] dihydrochloride 10 Granulated sugar 600 Flavor Q.s. Color Q.s. Sodium benzoate 1 'Deionized water Q.s.

All above ingredients are dissolved in water, combined and made up to a volume of one liter.

EXAMPLE 20 Ingredients: Mg./ tablet 1,1'-hexamethylenebis[1,2,3 ,4-tetrahydro-6,7

dimethoxyisoquinoline] dihydrochloride 50 Lactose USP (spray dried) Starch USP 20 Magnesium stearate USP 1 Stearic acid USP 5 Flavor Q.s.

These ingredients were passed through 60 mesh sieve, blended for 30 minutes and compressed directly into tablets on a suitable tablet press at a weight of 226 mg. using a biconcave, scored punch.

What is claimed is:

1. Method of treating a mammal to induce an increase in fibrinolytic activity in a mammal in need of such treatment, which comprises administering to said mammal a fibrinolytically effective amount of a compound of the following Formula A or a pharmaceutically acceptable addition salt thereof:

4. The method of claim 3 wherein said lower alkoxy is methoxy.

5. The method of claim 1 wherein said compound of Formula A is 1,1alkylenebis[1,2,3,4-tetrahydro-hydroxyisoquinoline] 6. The method of claim '1 wherein said compound of Formula A is a 1,1-alkylenebis[1,2,3,4-tetrahydro-lower alkoxy-hydroxy-isoquinoline] 7. The method of claim 1 wherein said compound of Formula A is a 1,1'-alkylenebis[1,2,3,4-tetrahydro-methyl isoquinoline] 8. The method of claim 1 wherein said compound of Formula A is 1,1-alkylenebis[1,2,3,4-tetrahydro-methylenedioxy-isoquinolinc] 9. Method in accordance in claim 1 wherein the compound of Formula A is: 1,1-tetramethylene-bis[1,2,31,4- tetrahydroisoquinoline] 10. Method in accordance with claim 1 wherein the compound of Formulae A is: 1,1-hexamethylene-bis[1,2, 3,4-tetrahydro-6-methoxyisoquinoline] 11. Method in accordance with claim 1 wherein the compound of Formula A is: 1,1'-hexamethylene-bis[1,2, 3,4-tetrahydroisoquinoline] 12. Method in accordance with claim 1 wherein the compound of Formula A is: 1,1-tetramethylene-bis[1,2, 3,4-tetrahydro-6,7-dimethoxyisoquinoline] 13. Method in accordance with claim -1 wherein the compound of Formula A is: 1,1'-decamethylene-bis[1,2, 3,4-tetrahydro-6,7-dimethoxyisoquinoline] References Cited UNITED STATES PATENTS 2,659,728 11/1953 Craig et al. 260-286 2,744,901 12/1953 Nabenhauer 260-286 3,138,600 6/1964 Fancher et al. 260286 FOREIGN PATENTS 922,828 1/1'955 Germany 260-286 OTHER REFERENCES J. Chem. Soc. 2010-21 (1929); Chemical Abstracts vol. 43 2624 (1949) (I); vol. 48 2254 (1954) (II); Vol. 49 6957 (1955) (111); vol. 52 12870 (1958) (IV); vol. 63 18053 (1965) (V); vol. 33 619 (VI).

ALBERT T. MEYERS, Primary Examiner F. E. WADDELL, Assistant Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,560 ,620 Dated February 2, 1971 Inventor-(s) Joseph Schol" t 8.1

It is certified that error appears in the above-identified pateni and that said Letters Patent are hereby corrected as shown below:

In column 1, the upper right-hand corner of Formula A for "R" R line 55, for "athrom-" read a thromline 70, for "potency" read patenoy line 71, for "acitvator" read activa Column 2, line 31, for "lyti cactivity" read lytic activity lines 3H-35, for "effeotice" read effective line 61, for "activ or" read activity on line 62, for "icidence" read incidence Column 3, line 29 for "alJ ylene-bis-[3, +-dihydroiso-" read allcylene bis[3,H-dihydroiso- Column H, line 26 for "filitration" read filtration line 28, for "diulent" read diluent Column 5, ll, for "product" read produced line 25, for "methanolethyl" re methanol-ethyl line 31, for "procedude" read procedure lin for the title of Example 4, read l,l'-I'ETRAIIBTHY1ENEBIS[1,2,3,H-TEIR B-I'IL'IHOXYISOQUINOLINEJ .DIHYDROQiLDRIDE Column 6, line 52, after "p read (9.1) Column 7, line 3, for "tetraisoquino-" read tetrahydroisoquinoline 13, after "suitable" read tablet 17, for "tetramethylene-" read tetrahydrolines 35, &7 and 60 To make the solution isotonic under the heading "Ampoule"; line for "Per ampoule" read Mg/Ampoule Column 9 line t, after "For A is" read a line 12, after "A is" read a Signed and sealed this 7th day of September 1971.

(SEAL) Attest:

EDNAHD M.FLETGI ER,JR.

Acting Commissioner of Pate