CA2015072A1 - Process for the preparation of glucosaminyl-epi-podophyllotoxin derivatives - Google Patents
Process for the preparation of glucosaminyl-epi-podophyllotoxin derivativesInfo
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- C07H15/00—Compounds containing hydrocarbon or substituted hydrocarbon radicals directly attached to hetero atoms of saccharide radicals
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Abstract
Abstract of the disclosure: HOE 89/B 015 A process for the preparation of glucosaminyl-epi-podo-phyllotoxin derivatives The invention relates to a novel process for the prepara-tion of glucosaminyl-epi-podophyllotoxin derivatives of the formula I
I
in which R1 is hydrogen or the acetyl or a mono-, di- or trihalo-genoacetyl protective group with halogen being fluor-ine, chlorine or bromine, R2 is hydrogen or (C1-C4)-alkyl, R3 hydrogen, (C1-C4)-alkyl or a benzyloxycarbonyl protective group, R4 is hydrogen, a mono-, di or trihalogenoacetyl pro-tective group, a benzyloxycarbonyl protective group or a methyl group, and A is C1-C4-alkyl, which comprises reacting a 3-0-acyl-2-N-benzyloxy-carbonyl-4,6-0-alkylidene-alpha-D-glucosamine derivative of the formula II, which is in the alpha-hydroxy form, II
in which R1 and R3 are acyl protective groups as defined above, and R2 is hydrogen, with a podophyllotoxin derivative of the formula III
III
in which R4 is a methyl group or a mono-, di- or trihalogenoacetyl or benzyloxycarbonyl protective group, in the presence of a promoter and of an anhydrous organic solvent at -50°C to 20°C to give a 4-O-(beta-glucosamin-yl)-epi-podophyllotoxin derivative of the formula I in which the radicals R1, R2, R3, and R4 retain their meaning as defined above, and subsequently converting the glyco-side products of the formula I, after elimination of the protective groups, into an amino or dialkylamino compound of the formula I.
I
in which R1 is hydrogen or the acetyl or a mono-, di- or trihalo-genoacetyl protective group with halogen being fluor-ine, chlorine or bromine, R2 is hydrogen or (C1-C4)-alkyl, R3 hydrogen, (C1-C4)-alkyl or a benzyloxycarbonyl protective group, R4 is hydrogen, a mono-, di or trihalogenoacetyl pro-tective group, a benzyloxycarbonyl protective group or a methyl group, and A is C1-C4-alkyl, which comprises reacting a 3-0-acyl-2-N-benzyloxy-carbonyl-4,6-0-alkylidene-alpha-D-glucosamine derivative of the formula II, which is in the alpha-hydroxy form, II
in which R1 and R3 are acyl protective groups as defined above, and R2 is hydrogen, with a podophyllotoxin derivative of the formula III
III
in which R4 is a methyl group or a mono-, di- or trihalogenoacetyl or benzyloxycarbonyl protective group, in the presence of a promoter and of an anhydrous organic solvent at -50°C to 20°C to give a 4-O-(beta-glucosamin-yl)-epi-podophyllotoxin derivative of the formula I in which the radicals R1, R2, R3, and R4 retain their meaning as defined above, and subsequently converting the glyco-side products of the formula I, after elimination of the protective groups, into an amino or dialkylamino compound of the formula I.
Description
2 ~ 2 BEHRINGWERKE AKTIENGESELLSCHAFT HOE 89/B 015 - Ma 764 Dr. Ha/Sd A process for the preparation of glucosaminyl-epi-podophyllotoxin derivatives _ The present invention relates to a process for the preparation of glucosaminyl-epi-podophylloto~in deriva-tives, especially 4-0-~4,6-O-alkylidene-beta-D-glucos-aminyl)-4~-demethyl-4-epi-podophyllotoxin derivatives, which, by reason of their cytostatic activity, are suitable for the treatment of cancers.
~lycosyl-epipodophyllotoxins are described in the specia-list literature. Two representatives of this class of substances, etoposide and teniposide, have been intro-duced as pharmaceuticals for the treatment of cancers.Etoposide derivatives which contain a glucosamine or N,N-dimethylglucosamine carbohydrate unit in place of the glucose unit show a broader spectr~m of activity than etoposide on preclinical investigation. Since these compounds are, by reason of the presence of the amino group, readily soluble in aqueous medium, compared with etoposide there are no problems in the preparation of pharmaceutical presentations from them.
Ep-A-o 141 057 and 0 196 618 describe etoposide deriva-tives which contain a glucosamine or ~,N-dimethylglucos-amine unit in place of the glucose.
~he said application EP-~-0 141 057 also discloses a process in which the compounds according to the inven~ion are prepared by reasting a functionalized beta-glucos-amine unit and 4'-O-protected epi-podophyllotoxin with catalysis ~y BF3. However, thi~ proce~s is elaborate and entails large losses because the de~ired epi-podophyllo-toxin glycoside is prepared starting from a beta-hydroxy-glycosylating component which can be prepared only by an elaborate method and is unstable because of m~tarotation.
2 ~ 7 ~
~rhe subsequent removal of the acyl prokective groups and the introduction of the 4'',6''-alkylidene group also entails large losses, and requires additional chromato-graphic purification steps, because of the large number of by-products.
Chemistry Letters, 799-802, 1987, discloses a process for the synthesis of beta-glucosaminyl-epi-podophyllotoxins, in which the glycosylating component i~ employed as 4,6-O-ethylideneglucosamine derivative. rrhe func$ionalized glucosEmine component, which is in the unstable beta-hydro~y form, yields, after glycosylation of the aglycon~
and subsequent elimination of the protective groups, the desired beta-glucosaminyl-epi-podophyllotoxin in 33%
yield.
lS Tt has been found, surprisingly, that the preferred product of the glycosylation o~ 4'-O-Z-4-epi-podophyllo-toxin (Z: benzyloxycarbonyl) with a functionalized glucosamine unit, which is in the alpha-hydroxy form, with catalysis by BF3 in ethyl acetate is the beta-glyco-~ide. ThP beta-glycosylation of epi-podophyllotoxins, as hitherto described in the specialist literature, takes place via the carbonium ion on carbon atom 4 of the aglycone, it being neces~ary ~or there to be nucleophilic attack of the beta-hydroxyl group of the glucosamine ~5 unit. The alpha-hydroxy form of the glycosylating unit is, because of the anomeric effect, energetically more stable than the beta-hydroxy form, with the alpha-hydroxy glucosamine derivatives being more straightforward ~o synthesize than the beta-hydroxy analogs, and thus the process according to the invention represents a novel and advantageous way for the industrial preparation of beta-glucosaminyl-epi-podophyllotoxins.
The in~ention has the object of developing a novel process which provides 4-0-(4,6-O-alkylidene-b2ta-D
glucosaminyl)-4' O-demethyl-4-epi-podophyllo~oxin deriva-tives in good yields and which is simpler than the known 20~7t~
~lycosyl-epipodophyllotoxins are described in the specia-list literature. Two representatives of this class of substances, etoposide and teniposide, have been intro-duced as pharmaceuticals for the treatment of cancers.Etoposide derivatives which contain a glucosamine or N,N-dimethylglucosamine carbohydrate unit in place of the glucose unit show a broader spectr~m of activity than etoposide on preclinical investigation. Since these compounds are, by reason of the presence of the amino group, readily soluble in aqueous medium, compared with etoposide there are no problems in the preparation of pharmaceutical presentations from them.
Ep-A-o 141 057 and 0 196 618 describe etoposide deriva-tives which contain a glucosamine or ~,N-dimethylglucos-amine unit in place of the glucose.
~he said application EP-~-0 141 057 also discloses a process in which the compounds according to the inven~ion are prepared by reasting a functionalized beta-glucos-amine unit and 4'-O-protected epi-podophyllotoxin with catalysis ~y BF3. However, thi~ proce~s is elaborate and entails large losses because the de~ired epi-podophyllo-toxin glycoside is prepared starting from a beta-hydroxy-glycosylating component which can be prepared only by an elaborate method and is unstable because of m~tarotation.
2 ~ 7 ~
~rhe subsequent removal of the acyl prokective groups and the introduction of the 4'',6''-alkylidene group also entails large losses, and requires additional chromato-graphic purification steps, because of the large number of by-products.
Chemistry Letters, 799-802, 1987, discloses a process for the synthesis of beta-glucosaminyl-epi-podophyllotoxins, in which the glycosylating component i~ employed as 4,6-O-ethylideneglucosamine derivative. rrhe func$ionalized glucosEmine component, which is in the unstable beta-hydro~y form, yields, after glycosylation of the aglycon~
and subsequent elimination of the protective groups, the desired beta-glucosaminyl-epi-podophyllotoxin in 33%
yield.
lS Tt has been found, surprisingly, that the preferred product of the glycosylation o~ 4'-O-Z-4-epi-podophyllo-toxin (Z: benzyloxycarbonyl) with a functionalized glucosamine unit, which is in the alpha-hydroxy form, with catalysis by BF3 in ethyl acetate is the beta-glyco-~ide. ThP beta-glycosylation of epi-podophyllotoxins, as hitherto described in the specialist literature, takes place via the carbonium ion on carbon atom 4 of the aglycone, it being neces~ary ~or there to be nucleophilic attack of the beta-hydroxyl group of the glucosamine ~5 unit. The alpha-hydroxy form of the glycosylating unit is, because of the anomeric effect, energetically more stable than the beta-hydroxy form, with the alpha-hydroxy glucosamine derivatives being more straightforward ~o synthesize than the beta-hydroxy analogs, and thus the process according to the invention represents a novel and advantageous way for the industrial preparation of beta-glucosaminyl-epi-podophyllotoxins.
The in~ention has the object of developing a novel process which provides 4-0-(4,6-O-alkylidene-b2ta-D
glucosaminyl)-4' O-demethyl-4-epi-podophyllo~oxin deriva-tives in good yields and which is simpler than the known 20~7t~
processes. In particular, the aim is to develop a novel process for the preparation of a suitable glucosamine-glycosylating component as well as novel deacylation processes for removing the acyl protec~ive group from glucosaminyl-epi-podophyllotoxins.
This object is achieved according to the invention by the process for the preparation of a gluco6aminyl-epi podo-phyllotoxin derivativP of the formula I
A~o~\ o ~o~o ~1 ~2-N ~ I
~~1~
Me~ ~ O~le O-R~
in which R1 is hydrogen or the acetyl or a mono-, di~ or trihalo-genoacetyl protective group with halogen being fluor-ine, chlorine or bromine, R~ is hydrogen or (Cl-C4)-alkyl, 5 R3 is hydrogen, (Cl-C4)-alkyl or a benzylox~carbonyl protective group, R4 is hydrogen, a mono-, di- or trihalogenoacetyl pro-tective group, a benzyloxycarbonyl protective group or a methyl group, and A is Cl-C4-alkyl, which comprises reacting a glucosamine derivative of the formula II, which i6 in the alpha-hydroxy form, 0~
~1~ ~ II
2 ~1 ~ 0 7 r~
in which R1 and R3 are acyl protective groups as defined above, and R2 is hydrogen and A is Cl-C4-alkyl, with a podophyllotoxin derivative of the formula III
Q~
<o~l~
' 0 III
rleO ~ or o_R4 in which R4 is a methyl group or a mono-, di- or trihalogenoacetyl or benzyloxycarbonyl protective group t in the presence of a promoter such as BF3.ether or of a tri-(Cl-C4) alkylsilyl trifluoromethanesulfonate and of an.
anhydrous organic solvent at -50aC to 20C to give a 4-O-(beta-glucosaminyl)-epi-podophyllotoxin derivative of ~: the formula I in which the radicals R1, RZ, R3, R4 and A
retain their meaning as defined above, subsequently eliminating the benzyloxycarbonyl protective group by hydrogenolysis using a palladium catalyst, eliminating the acetyl protective group using zinc dichloride or diacetate and eliminating the halogenoacetyl pxotective groups using a basic anion exchanger in an organic solv~nt such as methanol, ethanol, acetone, ethyl acetate or mixtures thereof with water where appropriate, and, where appropxiate, reacting the free amino group under the conditions of reductive alkylation with a Cl-C4-aldehyde in the presence of a hydride to give a mono- or dialkylamino derivative, there being formation of a 4-O-(beta-ylucosaminyl)-epi-podophyllotoxin derivative of the formula I in which R1 is hydrogen, R2 and R3 ~re hydrogen or (Cl-C4)-alkyl, R4 is hydrogen or the meth~l group and A is C1-C4-alkyl.
20~72 The compounds of the formula I which are preferably prepared by the process according ~o the invention are those in which Rl is hydrogen or acetyl or chloroacetyl protective group S R2 i8 hydrogen or (Cl-C4)-alkyl R3 is hydrogen, (Cl-C4)-alkyl or benzyloxycarbonyl protective group R4 is hydrogen, methyl or benzyloxycarbonyl or chloro-acetyl protective groups and A is methyl.
~he specific procedure for this is as follows: in the first place, starting from the 1,3-di-0-acyl precursor of the formula IV
A~o~\
R~HN "rOR~ . IV
~:O-O-CH2 Ph the glucosamine-glycosylating component of the formula V
~~
0~~ V
Rl Ht CO-O-CH2 P~
in which R1 and R5 are an acetyl or mono-, di- or trihalo-genoacetyl protective group and A is Cl-C4~alkyl, is prepared in the following manner: when R5 i5 an acetyl group, the precursor is treated with a weak organic base such as piperidine or pyridine, and when R5 is a halo-genoacetyl protective group, the precursor is treated with silica gel in a polar organic solvent such as methanol or ethanol.
The glucosamine compound is converted into the energeti-cally more stable alpha form by dissolving the products 20~7~
in a non-polar solvent such as chloroform, dichloro-methane.
~he glycosylation of a podophyllotoxin derivative of the formula III with the glucosamine unit of the formula V
preferably takes place in ethyl acetate, where approp-riate with admixture of dichloromethane, chloroform, ether or acetone, in the presence of 1 to 50 equivalents, preferably 20 to 30 equivalent~, of BF3-ether or tri-(C1-C4~-alkylsilyl trifluoromethanesulfonate at -50C to 20C, preferably at -30C to -15C. A molecular sieve can be used, where appropriate, as acid trap or drying agent.
The elimination of the protective group from the 4-O-glucosaminyl-epi-podophyllotoxin derivative of the formula I is carried out as follows:
The benzyloxycarbonyl protective group is eliminated by hydrogenolysis using palladium/carbon or palladium/barium sulfate in methanol, ethanol, acetone or ethyl acetate.
The acetyl protective group i8 eliminated using anhydrous zinc diacetate or dichloride in methanol or ethanol at the reflux temperature.
The halogenoacetyl protective groups, preferably the chloroacetyl protective group, are eliminated using a basic anion exchanger ~uch as Dowex, preferably lx8, in an organic solvent such as methanol, ethanol, acetone, ethyl acetate, preferably methanol, or mixture~ thereof.
The products of the formula I, which have a free amino group on carbon atom 2'', are converted into mono-, but preferably into di-(Cl-C4)-alkylamine derivatives by reductive alkylation with a Cl-C4-aldehyde and a hydride such as sodium cyanoborohydride.
The examples which follow are intended to explain the invention without, howe~er, confining it to the compounds mentioned.
- 2~15~7~
Examp~e 1 Preparation of 2-N-benzyloxycarbonyl-1,3-di-O-acyl-4,6-G-ethylidene-alpha,beta-D-glucosamine derivatives 2-N-Ben~ylo~ycarbonyl-4,6-O-ethylidene-D-gluco~amine Icompound 1~
The title compound was prepared by the proce~s of H.
Saito et al., as described in Chemistry Letters, 799-802 (1987), as follows: starting from D-gluco~amine hydro-chloride and ben~yloxrcarbonyl chloride, in the presence of 2 equivalents of NaOH in water, 2-N-benzyloxycarbonyl-D-glucosamine was prepared and subse~uently converted with acetaldehyde, with catalysis by H2SO4, into the title compound.
1,3~Di-O-acetyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-alpha,beta-D-glucosamine (compound 2) Compound 1 was reacted with acetic anhydrid~ and pyri-dine, by the acylation process customary in carbohydrate chemistry, to give the title compound.
2-N-Benzyloxycarbonyl-1,3-bis-O-chloroacetyl-4,6-~-ethylidene-alpha,beta-D-glucosamine (compound 3) 33 g (97.2 mmol) of compound 1 were dissolved in 1,000 ml of dichloromethane and 300 ml of pyridine and, while stirring at 0C, 2.4 equivalents of chloroacetyl chloride dissolved in 500 ml of dichloromethane were added in portions. After 14 h, the reaction mixture was washed thoroughly with sodium phosphate buffer, pH 7.5, and the organic phase was dried and evaporated in vacuo. The residue was purified by column chromatography on silica gel (eluent: dichloromethane/ace~one, 10:1).
Yield: 45.4 g (95%) 2 ~ 2 1~ NMRs (300 MHz, H,H-COSY, CDCl3) delta: 7.4-7.3(m, 5H, Ph), 6.20 (d, lH, J(1,2) = 3.8 Hz, H-l), 5.28 (dd, lH, J(2,3) = 10.4 Hz, J(3,4) = 9.6 Hz, H-3), 5.11 (d, lH, Jg = 1~.5 Hz, CHPh), 5.03 (d, lH, Jg, C~Ph), 5.02 (d, lH, J(2,NH) = 9.5 Hz, NH), 4.70 (q, lH, J(CH,Me) = 5 Hz, CH=), 4.23 (ddd, lH, J((1,2), J(2,3), J(2,NH), H-2)~ 4-15 ~s, 2H, ClCH2~, 4.13 (dd, lH, Jg = 10.5 Hz, J(5,6e) =
This object is achieved according to the invention by the process for the preparation of a gluco6aminyl-epi podo-phyllotoxin derivativP of the formula I
A~o~\ o ~o~o ~1 ~2-N ~ I
~~1~
Me~ ~ O~le O-R~
in which R1 is hydrogen or the acetyl or a mono-, di~ or trihalo-genoacetyl protective group with halogen being fluor-ine, chlorine or bromine, R~ is hydrogen or (Cl-C4)-alkyl, 5 R3 is hydrogen, (Cl-C4)-alkyl or a benzylox~carbonyl protective group, R4 is hydrogen, a mono-, di- or trihalogenoacetyl pro-tective group, a benzyloxycarbonyl protective group or a methyl group, and A is Cl-C4-alkyl, which comprises reacting a glucosamine derivative of the formula II, which i6 in the alpha-hydroxy form, 0~
~1~ ~ II
2 ~1 ~ 0 7 r~
in which R1 and R3 are acyl protective groups as defined above, and R2 is hydrogen and A is Cl-C4-alkyl, with a podophyllotoxin derivative of the formula III
Q~
<o~l~
' 0 III
rleO ~ or o_R4 in which R4 is a methyl group or a mono-, di- or trihalogenoacetyl or benzyloxycarbonyl protective group t in the presence of a promoter such as BF3.ether or of a tri-(Cl-C4) alkylsilyl trifluoromethanesulfonate and of an.
anhydrous organic solvent at -50aC to 20C to give a 4-O-(beta-glucosaminyl)-epi-podophyllotoxin derivative of ~: the formula I in which the radicals R1, RZ, R3, R4 and A
retain their meaning as defined above, subsequently eliminating the benzyloxycarbonyl protective group by hydrogenolysis using a palladium catalyst, eliminating the acetyl protective group using zinc dichloride or diacetate and eliminating the halogenoacetyl pxotective groups using a basic anion exchanger in an organic solv~nt such as methanol, ethanol, acetone, ethyl acetate or mixtures thereof with water where appropriate, and, where appropxiate, reacting the free amino group under the conditions of reductive alkylation with a Cl-C4-aldehyde in the presence of a hydride to give a mono- or dialkylamino derivative, there being formation of a 4-O-(beta-ylucosaminyl)-epi-podophyllotoxin derivative of the formula I in which R1 is hydrogen, R2 and R3 ~re hydrogen or (Cl-C4)-alkyl, R4 is hydrogen or the meth~l group and A is C1-C4-alkyl.
20~72 The compounds of the formula I which are preferably prepared by the process according ~o the invention are those in which Rl is hydrogen or acetyl or chloroacetyl protective group S R2 i8 hydrogen or (Cl-C4)-alkyl R3 is hydrogen, (Cl-C4)-alkyl or benzyloxycarbonyl protective group R4 is hydrogen, methyl or benzyloxycarbonyl or chloro-acetyl protective groups and A is methyl.
~he specific procedure for this is as follows: in the first place, starting from the 1,3-di-0-acyl precursor of the formula IV
A~o~\
R~HN "rOR~ . IV
~:O-O-CH2 Ph the glucosamine-glycosylating component of the formula V
~~
0~~ V
Rl Ht CO-O-CH2 P~
in which R1 and R5 are an acetyl or mono-, di- or trihalo-genoacetyl protective group and A is Cl-C4~alkyl, is prepared in the following manner: when R5 i5 an acetyl group, the precursor is treated with a weak organic base such as piperidine or pyridine, and when R5 is a halo-genoacetyl protective group, the precursor is treated with silica gel in a polar organic solvent such as methanol or ethanol.
The glucosamine compound is converted into the energeti-cally more stable alpha form by dissolving the products 20~7~
in a non-polar solvent such as chloroform, dichloro-methane.
~he glycosylation of a podophyllotoxin derivative of the formula III with the glucosamine unit of the formula V
preferably takes place in ethyl acetate, where approp-riate with admixture of dichloromethane, chloroform, ether or acetone, in the presence of 1 to 50 equivalents, preferably 20 to 30 equivalent~, of BF3-ether or tri-(C1-C4~-alkylsilyl trifluoromethanesulfonate at -50C to 20C, preferably at -30C to -15C. A molecular sieve can be used, where appropriate, as acid trap or drying agent.
The elimination of the protective group from the 4-O-glucosaminyl-epi-podophyllotoxin derivative of the formula I is carried out as follows:
The benzyloxycarbonyl protective group is eliminated by hydrogenolysis using palladium/carbon or palladium/barium sulfate in methanol, ethanol, acetone or ethyl acetate.
The acetyl protective group i8 eliminated using anhydrous zinc diacetate or dichloride in methanol or ethanol at the reflux temperature.
The halogenoacetyl protective groups, preferably the chloroacetyl protective group, are eliminated using a basic anion exchanger ~uch as Dowex, preferably lx8, in an organic solvent such as methanol, ethanol, acetone, ethyl acetate, preferably methanol, or mixture~ thereof.
The products of the formula I, which have a free amino group on carbon atom 2'', are converted into mono-, but preferably into di-(Cl-C4)-alkylamine derivatives by reductive alkylation with a Cl-C4-aldehyde and a hydride such as sodium cyanoborohydride.
The examples which follow are intended to explain the invention without, howe~er, confining it to the compounds mentioned.
- 2~15~7~
Examp~e 1 Preparation of 2-N-benzyloxycarbonyl-1,3-di-O-acyl-4,6-G-ethylidene-alpha,beta-D-glucosamine derivatives 2-N-Ben~ylo~ycarbonyl-4,6-O-ethylidene-D-gluco~amine Icompound 1~
The title compound was prepared by the proce~s of H.
Saito et al., as described in Chemistry Letters, 799-802 (1987), as follows: starting from D-gluco~amine hydro-chloride and ben~yloxrcarbonyl chloride, in the presence of 2 equivalents of NaOH in water, 2-N-benzyloxycarbonyl-D-glucosamine was prepared and subse~uently converted with acetaldehyde, with catalysis by H2SO4, into the title compound.
1,3~Di-O-acetyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-alpha,beta-D-glucosamine (compound 2) Compound 1 was reacted with acetic anhydrid~ and pyri-dine, by the acylation process customary in carbohydrate chemistry, to give the title compound.
2-N-Benzyloxycarbonyl-1,3-bis-O-chloroacetyl-4,6-~-ethylidene-alpha,beta-D-glucosamine (compound 3) 33 g (97.2 mmol) of compound 1 were dissolved in 1,000 ml of dichloromethane and 300 ml of pyridine and, while stirring at 0C, 2.4 equivalents of chloroacetyl chloride dissolved in 500 ml of dichloromethane were added in portions. After 14 h, the reaction mixture was washed thoroughly with sodium phosphate buffer, pH 7.5, and the organic phase was dried and evaporated in vacuo. The residue was purified by column chromatography on silica gel (eluent: dichloromethane/ace~one, 10:1).
Yield: 45.4 g (95%) 2 ~ 2 1~ NMRs (300 MHz, H,H-COSY, CDCl3) delta: 7.4-7.3(m, 5H, Ph), 6.20 (d, lH, J(1,2) = 3.8 Hz, H-l), 5.28 (dd, lH, J(2,3) = 10.4 Hz, J(3,4) = 9.6 Hz, H-3), 5.11 (d, lH, Jg = 1~.5 Hz, CHPh), 5.03 (d, lH, Jg, C~Ph), 5.02 (d, lH, J(2,NH) = 9.5 Hz, NH), 4.70 (q, lH, J(CH,Me) = 5 Hz, CH=), 4.23 (ddd, lH, J((1,2), J(2,3), J(2,NH), H-2)~ 4-15 ~s, 2H, ClCH2~, 4.13 (dd, lH, Jg = 10.5 Hz, J(5,6e) =
4.5 Hz, H-6e), 4.02 (d, lH, Jg = 15 Hz, ClCH?-A~, 3.92 (d, lH, Jg, ClCH2-B), 3.79 (ddd, lH, J(5,6a) = 10 Hz, J15.6e), J (4,5), H-5), 3.58 (dd, lH, J(3,4), J(4,5), H-4), 3.5 (dd, lH, Jg, J(5,6a), H-6a), 1.33 (d, 3H, J(Me,CH), MeC=) Example ~
Preparation of 3-O-acyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-alpha-D-glucosamine derivatives 3-O-Acetyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-~lpha-D-gluocosamine (compound 4) 2.11 g (5 mmol) of compound 2 were dissolved in 40 ml of THF, and 0.5 ml of piperidine was added. After the reaction mixture had been stirred for 1~ h it was evapo-rated in vacuo and then distilled with toluene. The residue was dissolved in chloroform; the solution was thoroughly washed with ice-water, and the organic phase was dried over sodium sulfate. Th~ product was purified by column chromatography on silica gel (eluent: dichloro-methane/acetone 6:1). Yield: 1.67 g (88%) of syrup, ~23 = +29.1 (c=1 in chloroform) 2-N-Benzyloxycarbonyl-3-O-chloroacetyl-4,6-O-ethylidene-alpha-D-glucosamine (compound 5) 37 g (75.2 mmol) of compound 3 were dissolved in 500 ml of methanol, and 74 g of silica gel 60 t40 - 63 ~m) were added. The suspension was stirred at RT for 3 h. TLC~
dichloromethane/e~hyl acetate 1:1. The reaction mixture 2 ~ 7 2 g was filtered, and the solid phase was washed with methan-ol. The residue from evaporation of the organic phas~ was dissolved in dichloromethane/ethyl acetate and iiltered through 50 g of silica gel. The organic phase was evapo-rated in vacuo and then distilled with chloroform. Yield:
28.31 g (91~) of Byrupl [~D5 = +32.9~ (c=l in ethyl acetate) lH NMR (300 MHz, H,H-COSY, CDCl3) delta: 7.38-7.30 (m, 5H, Ph), 5.32 ~dd, lH, J(2,3) = 11 Hz, J(3,4) = 10 ~z, H-3), 5.26 td, lH, J(2,NH) = 10 Hz, NH)~ 5.23 (d, lH, J~1,2) =
3.5 Hz, H-1), 5.11 (d, lH, Jg = 12 Hz, CHPh), 5.03 ~d, lH, Jg = 12 Hz, CHPh), 4.69 (q, lH, J(Ne,CH) = 5 Hz, CH=), 4.09 (dd, lH, J(5,6e) = 4.7 Hz, Jg = 10 Hz, H-6), 4.04 (d~ lH~ J(1,2), J(2,NH), J(2,3), H-2), 4.02 (d, lH, Jg = 14.6 Hz, ClCH), 3.99 (ddd, lH, J(4,5) = 10 Hz, J
(5,6a) = 10 Hz, J(5,6e) = 4.7 Hæ, H-5), 3.92 (d, lH, Jg, ClCH), 3.52 (dd, lH, J(5,6~, Jg, H-6a), 3.48 (dd, lH, J(3,4), J(4,5), H-4), 1.32 (d, 3H, J(Me,CH), MeC=).
Example 3 Glycosylation of podophyllotoxin derivati~es 4-O-(3-O-Acetyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-beta-D-glucosaminyl)-4'-O-benzyloxycarbonyl 4~-O de-methyl-4-epi-podophyllotoxin (compound 6) 2.8 g (5.2 mmol) of 4'-O-benzyloxycarbonyl-4'-O-demethyl-4-epi-podophyllotoxin and l.9 g (5.2 mmol~ of compound 4 were dissolved in 300 ml of ethyl acetate. 5 g of 4 molecular sieves were added and then the reaction mixture was cooled to -18C, and 39 g of BF3.ether were added.
The reaction mixture was stirred at -18C for 6 h (T~C:
dichloromethane/acetone lO:1). It was then neutralized with 40 ml of triethylamine and filtered. The organic phase was evapor~ted in vacuo, the re~idue was dissolved in chloroform, and the ~olution was thoroughly washed with water. The organic phase was dried over sodium sulfate and evaporated. The resulting product was puri-fied by column chromatography on silica gel (eluent:
dichloromethanP/acetone 10.1).
~ield: 3.6 g (78%) lH NMR ~300 MHZ, H,H-COSY, CDC13) delta: 7.38-7.19 (m, 10H, Ph), 6.68 (s, lH, H-5), 6.44 (s, lH, H-8), 6.18 (s, 2H, H-2' and -6'), 5.88 (fi, lH, H~15a), 5.73 (s, lH, H-15b), 5.20 (~, 2H, H2Ph), 5.12 (dd, lH, J(2'',3''~ =
10 Hz, E-3''), 5.00 (d, 1~, Jg = 12.5 Hzt CH2Ph-A), 4.84 (d, lH, Jg, ~ , 4.82 (d, ~H, J(3,4) = 3 ~z~ H-4)~
4.79 (d, lH, J(2~', NH) c 10 Hz, NH), 4.69 (d, lH, J(1'',2'') = 8.5 Hz, H-1''), 4.69 (q, lH, J(CH,Me) = 5 Hz, MeCH=), 4.45 (d, lH, J(1,2) = 5 Hz, H-l), 4.41 (dd, lH, J(3,11a) = 9 Hz, Jg = 9 Hz, H-lla), 4.18 (dd, lH, Jg, J(3,11b) - 7 Hz, H-llb), 4.15 (dd, lH, Jg = 10 Hz, J(5'',6~'e) = 4.5 Hz, H-6~e), 3.60 (s, 3H, MeO3, 3.56 (ddd, lH, J(1'',2''), J(2'', NH), J(2''~3'')~ H-2'')~
3.54 (dd, lH, Jg, J(5'',6''a) = 10 Hz, H 6''a), 3.40 (dd~
lH, J(3~',4''), J(4'',5'~) = 9.5 Hz, H-4~'), 3.33 (ddd, lH, J(4'',5''~, J(5'',6''a), J(5'',Ç''e), H-5''), 3.19 (dd, lH, J(1,2), J(2,3) = 14 Hz, H-2~, 2.77 (m, lH, J(2,3), J(3,4), J(3,11a), J(3,11b), H-3), 1.97 (8, 3H, acetyl), 1.28 (d, 3H, J(CH,Me) = 5 Hz, MeC=).
4'-O-Benzyloxycarbonyl 4-0-(2-N-benzyloxycarbonyl-3-O
chloroacetyl-4,6-O-ethylidene-beta-D-glucosaminyl)-4~-O-demethyl-4-epi-podophyllotoxin (compound 7) 13 g (25 mmol) of 4'-O-benzyloxycarbonyl-4'-O-demethyl 4-epi-podop~yllotoxin and 10 g (25 mmol) of compound 5 were dissolved in 400 ml of dichloromethane/ethyl acetate 1:1, and 23 g of 4 ~ molecular sieves were added. The reaction mixture was cooled to -18~C and, while ~tirring, 80 ml of BF3.ether were added in portions. After stirring at -18C for 4 h, a fur~her 4.0 g of aglycone, dissolved in 50 ml of ethyl ace~ate, were added. After 10 h, B0 ml of triethylamine were added to the reaction mixture at -18~C. The xeaction mixture was filtered and evaporated - 20~7~
in vacuo. The residue was dissolved in chloroform and thorou~hly washed with ice-water. ~he organic phase was dried over sodium sulfate and evaporated in vacuo. The product was purified by column chromatography on silica gel (eluent: dichloromethane/acetone 15:1). Yield: 17 g (74%)/ t~lD = ~ 2S (c=0.2 in CHCl3) Melting point: 140 - 142 JC
H ~MR (300 NHz, H,H-COSY, CDCl3) delta: 7.30-7.44 (m, 10H, Ph), 6.74 (s, lH, H-5), 6.50 (s, lH, H-8), 6-~4 (St 2H, H-2' and H-6'), 5.93 (s, lH, H-lSa), 5.76 (s, lH, H-15b), 5.33 (dd, lH, J(2'~,3'') = 10 Hz, J(3'',4'') = 10 Hz, H-3''), 5.26 (s, 2H, Ch2Ph), 5.05 (d, lH, Jg = 12.5 Hz, CH-Ph-A), 4.93 td, lH, Jg = 12.5 Hz, CH-Ph-B), 4.89 ~d, lH, J(1'',2l') = 7.5 Hz, H-1''), 4.89 (d, lH, Jt3,4) = 3 Hz, H-4), 4.89 (d, lH, J(2'',NH) = 9.5 Hz, NH), 4.70 (q, lH, J(Me,CH) = 5 Hz, Me-CH=), 4.52 (d, lH, J(1,2) =
5.3 Hz, H-l), 4.45 (dd, lH, Jg = 9 Hz, J(3,11a) = 10 Hz, H-lla), 4.24 (dd, lE, Jg, J(3,11b) = 7 Hz, H-llb), 4.22 (dd, lH, Jg = ~0.5 Hz, J(5''t6''e~ = 4.5 Hz, H-6''e), 4.06 (d, lH, Jg = 15 Hz, ClAc), 3.99 (d, lH, Jg = 15 Hz, ClAc), 3.66 (s, 3H, MeO), 3.60 (dd~ lH, J~3~',4'~) = 9 Hz, J(4~,5~) = 9 Hz, H-S~), 3.23 (dd, lH, J(2,3) = 14 Hz, J(1,2), H-2), 2.83 (m, lH, J(2,3), J(3,4), J(3,11a), J(3,11b), H-3), 1.34 (s, 3H, J(Me,CH) = 5 Hzl MeC=).
4-O-(2-N-Benzyloxycarbonyl-3-O-chloroacetyl-4,6-O-ethyli-dene-beta-D-glucosaminyl)-4'-O-chloroacetyl-4'-O-de-methyl-4-epi-podophyllotoxin ~compound 8~
The title compound was prapared starting from 200 mg (0.42 mmol) o~ 4'-O-chloroacetyl-4'-O-demethyl-4-epi-podophyllotoxin and 175 mg ~O.42 ~mol) of compound 5 by the procedure for the preparation of compound 7 and was characterized by lH and 13C NMR spectra.
Yield- 257 mg (70%3 4-O-~2-N-Benzyloxycarbonyl-3-O-chloroacetyl-4,6-O-ethyli-dene-beta-D-glucosaminyl~-4-epi-podophyllotoxin 2~5~
~compound 9) The title compound was preparsd starting from 150 mg (0.36 mmol) of podophyllotoxin and 150 mg ~0.36 mmol~ of compound 5 by the procedure for the preparation of compound 7 and was characterized by lH and 13C NMR
~pectra. Yield: 190 mg (65~) ExamJæle 4 Deacylation of the glucosaminides 4-O-t2-N-Benzyloxycarbonyl-4,6-O-ethylidene-beta-D-glucosaminyl) 4'-O-benzyloxycarbonyl-4'-O-demethyl-4-epi-podophyllotoxin (compound 10) a) Deacylation of the 3''-O-chloroacetyl derivati~e (compound 7) 2.5 g (2.4 mmol) of compound 7 were dissolved in 500 ml lS of methanol, and 5 g of Dowex lx8 ion exchanger were added. After stirring at room temperature for 2 h, the resin was filtered off and thoroughly wa~hed with methan-ol. ~he organic phase was evaporated in vacuo, and the residue was dissolved in chloroform and thoroughly washed. The organic phase was dried over sodium sulfate and evaporated in vacuo, Yield: 1.95 g (98~), t~]20 =
-~5.4 (c=1 in chloroform) The title compound w~s characterized by NMR spectroscopy.
b) Deacylation of the 3''-O-acetyl der.ivative (compound 6) 600 mg (0.~1 mmol) of compound 6 were dis601ved in 50 ml of dry methanol, and 83 mg of zinc dichloride were added.
Th~ reaction mixture was refluxed for 3 d. After the usual working up, the product was purified by column chromatography. Yield: 377 mg (65%~
2 ~
_ 13 -4-O-(2-N-Benzyloxycarbonyl-4,6-O ethylidene-beta-D-glucosaminyl)-4-epi-podophyllotoxin (compound 11) 190 mg ~0.234 mmol) of compound 9 were deblocked with Dowex to give the title compound by the procedure for the 5 deacylation of compound 7.
Yield: 160 mg (93%) Example 5 Elimination of the N- or O-benzyloxycarbonyl protective group by hydrogenolysis 4'-0-Demethyl-4-epi-4-0-(4,6-O-ethylidene-beta-D-glucos-aminyl)-podophyllotoxin ~compound 12) 1.5 g (1.88 mmol) of compound 10 were dissolved in 100 ml of methanol, and 0.45 g of palladium/carbon was added.
The reaction mixture was hydrogenated at room temperature under atmospheric pressure for 1 h. The mixture was.
filtered and evaporated in vacuo. The product crystall-izes from methanol/ethyl acetate. Yield: 0.95 g (90%) t~]20 = _ 115.4 (c=1 in methanol) Melting point: 202 - 204C
4-Epi-4-O-(4,6-O-ethylidene-beta-D-glucosaminyl)-podo-phyllotoxin ~compound 13) Staxting from 160 mg (0.217 mmol) of compound 11, the title compound was hydrogenated and worked up ~y the procedure for the preparation of compound 12. Yield:
117 mg ~90~
- 2 ~
ExamPle 6 Reductive alkylation of 2''-amino derivati~es 4'-O-Demethyl-4-0-(2-N,N-dLmethyl-4,6-O-ethylidene-beta-D-glucosaminyl)-4-epi-podophyllotoxin (compound 14) 2.5 g (4.25 mmol) of compound 12 were dissolved ~n 200 ml of methanol, and 4 ml of a 37% strength aqueous foxmalde-hyde solution and 1.06 g of sodium cyanoborohydride were added. The reaction mixture was stirred for 1 h and then evaporated in vacuo, and the residue was purified by column chromatography on silica gel (eluent: dichloro-methane/methanol 10:1). Yield: 2 g (76%), [~] DO = - 113.2 (c=1 in chloroform) 4-O-(2-N,N-Dimethyl-4,6-O-ethylidene-beta-D-glucos-aminyl)-4-epi-podophyllotoxin (compound 15) The title compound wa~ prepared starting from 110 mg (0.18 mmol) of compound 13 by the procedure for the preparation of compound 14. Yield: 95 mg (75%)
Preparation of 3-O-acyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-alpha-D-glucosamine derivatives 3-O-Acetyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-~lpha-D-gluocosamine (compound 4) 2.11 g (5 mmol) of compound 2 were dissolved in 40 ml of THF, and 0.5 ml of piperidine was added. After the reaction mixture had been stirred for 1~ h it was evapo-rated in vacuo and then distilled with toluene. The residue was dissolved in chloroform; the solution was thoroughly washed with ice-water, and the organic phase was dried over sodium sulfate. Th~ product was purified by column chromatography on silica gel (eluent: dichloro-methane/acetone 6:1). Yield: 1.67 g (88%) of syrup, ~23 = +29.1 (c=1 in chloroform) 2-N-Benzyloxycarbonyl-3-O-chloroacetyl-4,6-O-ethylidene-alpha-D-glucosamine (compound 5) 37 g (75.2 mmol) of compound 3 were dissolved in 500 ml of methanol, and 74 g of silica gel 60 t40 - 63 ~m) were added. The suspension was stirred at RT for 3 h. TLC~
dichloromethane/e~hyl acetate 1:1. The reaction mixture 2 ~ 7 2 g was filtered, and the solid phase was washed with methan-ol. The residue from evaporation of the organic phas~ was dissolved in dichloromethane/ethyl acetate and iiltered through 50 g of silica gel. The organic phase was evapo-rated in vacuo and then distilled with chloroform. Yield:
28.31 g (91~) of Byrupl [~D5 = +32.9~ (c=l in ethyl acetate) lH NMR (300 MHz, H,H-COSY, CDCl3) delta: 7.38-7.30 (m, 5H, Ph), 5.32 ~dd, lH, J(2,3) = 11 Hz, J(3,4) = 10 ~z, H-3), 5.26 td, lH, J(2,NH) = 10 Hz, NH)~ 5.23 (d, lH, J~1,2) =
3.5 Hz, H-1), 5.11 (d, lH, Jg = 12 Hz, CHPh), 5.03 ~d, lH, Jg = 12 Hz, CHPh), 4.69 (q, lH, J(Ne,CH) = 5 Hz, CH=), 4.09 (dd, lH, J(5,6e) = 4.7 Hz, Jg = 10 Hz, H-6), 4.04 (d~ lH~ J(1,2), J(2,NH), J(2,3), H-2), 4.02 (d, lH, Jg = 14.6 Hz, ClCH), 3.99 (ddd, lH, J(4,5) = 10 Hz, J
(5,6a) = 10 Hz, J(5,6e) = 4.7 Hæ, H-5), 3.92 (d, lH, Jg, ClCH), 3.52 (dd, lH, J(5,6~, Jg, H-6a), 3.48 (dd, lH, J(3,4), J(4,5), H-4), 1.32 (d, 3H, J(Me,CH), MeC=).
Example 3 Glycosylation of podophyllotoxin derivati~es 4-O-(3-O-Acetyl-2-N-benzyloxycarbonyl-4,6-O-ethylidene-beta-D-glucosaminyl)-4'-O-benzyloxycarbonyl 4~-O de-methyl-4-epi-podophyllotoxin (compound 6) 2.8 g (5.2 mmol) of 4'-O-benzyloxycarbonyl-4'-O-demethyl-4-epi-podophyllotoxin and l.9 g (5.2 mmol~ of compound 4 were dissolved in 300 ml of ethyl acetate. 5 g of 4 molecular sieves were added and then the reaction mixture was cooled to -18C, and 39 g of BF3.ether were added.
The reaction mixture was stirred at -18C for 6 h (T~C:
dichloromethane/acetone lO:1). It was then neutralized with 40 ml of triethylamine and filtered. The organic phase was evapor~ted in vacuo, the re~idue was dissolved in chloroform, and the ~olution was thoroughly washed with water. The organic phase was dried over sodium sulfate and evaporated. The resulting product was puri-fied by column chromatography on silica gel (eluent:
dichloromethanP/acetone 10.1).
~ield: 3.6 g (78%) lH NMR ~300 MHZ, H,H-COSY, CDC13) delta: 7.38-7.19 (m, 10H, Ph), 6.68 (s, lH, H-5), 6.44 (s, lH, H-8), 6.18 (s, 2H, H-2' and -6'), 5.88 (fi, lH, H~15a), 5.73 (s, lH, H-15b), 5.20 (~, 2H, H2Ph), 5.12 (dd, lH, J(2'',3''~ =
10 Hz, E-3''), 5.00 (d, 1~, Jg = 12.5 Hzt CH2Ph-A), 4.84 (d, lH, Jg, ~ , 4.82 (d, ~H, J(3,4) = 3 ~z~ H-4)~
4.79 (d, lH, J(2~', NH) c 10 Hz, NH), 4.69 (d, lH, J(1'',2'') = 8.5 Hz, H-1''), 4.69 (q, lH, J(CH,Me) = 5 Hz, MeCH=), 4.45 (d, lH, J(1,2) = 5 Hz, H-l), 4.41 (dd, lH, J(3,11a) = 9 Hz, Jg = 9 Hz, H-lla), 4.18 (dd, lH, Jg, J(3,11b) - 7 Hz, H-llb), 4.15 (dd, lH, Jg = 10 Hz, J(5'',6~'e) = 4.5 Hz, H-6~e), 3.60 (s, 3H, MeO3, 3.56 (ddd, lH, J(1'',2''), J(2'', NH), J(2''~3'')~ H-2'')~
3.54 (dd, lH, Jg, J(5'',6''a) = 10 Hz, H 6''a), 3.40 (dd~
lH, J(3~',4''), J(4'',5'~) = 9.5 Hz, H-4~'), 3.33 (ddd, lH, J(4'',5''~, J(5'',6''a), J(5'',Ç''e), H-5''), 3.19 (dd, lH, J(1,2), J(2,3) = 14 Hz, H-2~, 2.77 (m, lH, J(2,3), J(3,4), J(3,11a), J(3,11b), H-3), 1.97 (8, 3H, acetyl), 1.28 (d, 3H, J(CH,Me) = 5 Hz, MeC=).
4'-O-Benzyloxycarbonyl 4-0-(2-N-benzyloxycarbonyl-3-O
chloroacetyl-4,6-O-ethylidene-beta-D-glucosaminyl)-4~-O-demethyl-4-epi-podophyllotoxin (compound 7) 13 g (25 mmol) of 4'-O-benzyloxycarbonyl-4'-O-demethyl 4-epi-podop~yllotoxin and 10 g (25 mmol) of compound 5 were dissolved in 400 ml of dichloromethane/ethyl acetate 1:1, and 23 g of 4 ~ molecular sieves were added. The reaction mixture was cooled to -18~C and, while ~tirring, 80 ml of BF3.ether were added in portions. After stirring at -18C for 4 h, a fur~her 4.0 g of aglycone, dissolved in 50 ml of ethyl ace~ate, were added. After 10 h, B0 ml of triethylamine were added to the reaction mixture at -18~C. The xeaction mixture was filtered and evaporated - 20~7~
in vacuo. The residue was dissolved in chloroform and thorou~hly washed with ice-water. ~he organic phase was dried over sodium sulfate and evaporated in vacuo. The product was purified by column chromatography on silica gel (eluent: dichloromethane/acetone 15:1). Yield: 17 g (74%)/ t~lD = ~ 2S (c=0.2 in CHCl3) Melting point: 140 - 142 JC
H ~MR (300 NHz, H,H-COSY, CDCl3) delta: 7.30-7.44 (m, 10H, Ph), 6.74 (s, lH, H-5), 6.50 (s, lH, H-8), 6-~4 (St 2H, H-2' and H-6'), 5.93 (s, lH, H-lSa), 5.76 (s, lH, H-15b), 5.33 (dd, lH, J(2'~,3'') = 10 Hz, J(3'',4'') = 10 Hz, H-3''), 5.26 (s, 2H, Ch2Ph), 5.05 (d, lH, Jg = 12.5 Hz, CH-Ph-A), 4.93 td, lH, Jg = 12.5 Hz, CH-Ph-B), 4.89 ~d, lH, J(1'',2l') = 7.5 Hz, H-1''), 4.89 (d, lH, Jt3,4) = 3 Hz, H-4), 4.89 (d, lH, J(2'',NH) = 9.5 Hz, NH), 4.70 (q, lH, J(Me,CH) = 5 Hz, Me-CH=), 4.52 (d, lH, J(1,2) =
5.3 Hz, H-l), 4.45 (dd, lH, Jg = 9 Hz, J(3,11a) = 10 Hz, H-lla), 4.24 (dd, lE, Jg, J(3,11b) = 7 Hz, H-llb), 4.22 (dd, lH, Jg = ~0.5 Hz, J(5''t6''e~ = 4.5 Hz, H-6''e), 4.06 (d, lH, Jg = 15 Hz, ClAc), 3.99 (d, lH, Jg = 15 Hz, ClAc), 3.66 (s, 3H, MeO), 3.60 (dd~ lH, J~3~',4'~) = 9 Hz, J(4~,5~) = 9 Hz, H-S~), 3.23 (dd, lH, J(2,3) = 14 Hz, J(1,2), H-2), 2.83 (m, lH, J(2,3), J(3,4), J(3,11a), J(3,11b), H-3), 1.34 (s, 3H, J(Me,CH) = 5 Hzl MeC=).
4-O-(2-N-Benzyloxycarbonyl-3-O-chloroacetyl-4,6-O-ethyli-dene-beta-D-glucosaminyl)-4'-O-chloroacetyl-4'-O-de-methyl-4-epi-podophyllotoxin ~compound 8~
The title compound was prapared starting from 200 mg (0.42 mmol) o~ 4'-O-chloroacetyl-4'-O-demethyl-4-epi-podophyllotoxin and 175 mg ~O.42 ~mol) of compound 5 by the procedure for the preparation of compound 7 and was characterized by lH and 13C NMR spectra.
Yield- 257 mg (70%3 4-O-~2-N-Benzyloxycarbonyl-3-O-chloroacetyl-4,6-O-ethyli-dene-beta-D-glucosaminyl~-4-epi-podophyllotoxin 2~5~
~compound 9) The title compound was preparsd starting from 150 mg (0.36 mmol) of podophyllotoxin and 150 mg ~0.36 mmol~ of compound 5 by the procedure for the preparation of compound 7 and was characterized by lH and 13C NMR
~pectra. Yield: 190 mg (65~) ExamJæle 4 Deacylation of the glucosaminides 4-O-t2-N-Benzyloxycarbonyl-4,6-O-ethylidene-beta-D-glucosaminyl) 4'-O-benzyloxycarbonyl-4'-O-demethyl-4-epi-podophyllotoxin (compound 10) a) Deacylation of the 3''-O-chloroacetyl derivati~e (compound 7) 2.5 g (2.4 mmol) of compound 7 were dissolved in 500 ml lS of methanol, and 5 g of Dowex lx8 ion exchanger were added. After stirring at room temperature for 2 h, the resin was filtered off and thoroughly wa~hed with methan-ol. ~he organic phase was evaporated in vacuo, and the residue was dissolved in chloroform and thoroughly washed. The organic phase was dried over sodium sulfate and evaporated in vacuo, Yield: 1.95 g (98~), t~]20 =
-~5.4 (c=1 in chloroform) The title compound w~s characterized by NMR spectroscopy.
b) Deacylation of the 3''-O-acetyl der.ivative (compound 6) 600 mg (0.~1 mmol) of compound 6 were dis601ved in 50 ml of dry methanol, and 83 mg of zinc dichloride were added.
Th~ reaction mixture was refluxed for 3 d. After the usual working up, the product was purified by column chromatography. Yield: 377 mg (65%~
2 ~
_ 13 -4-O-(2-N-Benzyloxycarbonyl-4,6-O ethylidene-beta-D-glucosaminyl)-4-epi-podophyllotoxin (compound 11) 190 mg ~0.234 mmol) of compound 9 were deblocked with Dowex to give the title compound by the procedure for the 5 deacylation of compound 7.
Yield: 160 mg (93%) Example 5 Elimination of the N- or O-benzyloxycarbonyl protective group by hydrogenolysis 4'-0-Demethyl-4-epi-4-0-(4,6-O-ethylidene-beta-D-glucos-aminyl)-podophyllotoxin ~compound 12) 1.5 g (1.88 mmol) of compound 10 were dissolved in 100 ml of methanol, and 0.45 g of palladium/carbon was added.
The reaction mixture was hydrogenated at room temperature under atmospheric pressure for 1 h. The mixture was.
filtered and evaporated in vacuo. The product crystall-izes from methanol/ethyl acetate. Yield: 0.95 g (90%) t~]20 = _ 115.4 (c=1 in methanol) Melting point: 202 - 204C
4-Epi-4-O-(4,6-O-ethylidene-beta-D-glucosaminyl)-podo-phyllotoxin ~compound 13) Staxting from 160 mg (0.217 mmol) of compound 11, the title compound was hydrogenated and worked up ~y the procedure for the preparation of compound 12. Yield:
117 mg ~90~
- 2 ~
ExamPle 6 Reductive alkylation of 2''-amino derivati~es 4'-O-Demethyl-4-0-(2-N,N-dLmethyl-4,6-O-ethylidene-beta-D-glucosaminyl)-4-epi-podophyllotoxin (compound 14) 2.5 g (4.25 mmol) of compound 12 were dissolved ~n 200 ml of methanol, and 4 ml of a 37% strength aqueous foxmalde-hyde solution and 1.06 g of sodium cyanoborohydride were added. The reaction mixture was stirred for 1 h and then evaporated in vacuo, and the residue was purified by column chromatography on silica gel (eluent: dichloro-methane/methanol 10:1). Yield: 2 g (76%), [~] DO = - 113.2 (c=1 in chloroform) 4-O-(2-N,N-Dimethyl-4,6-O-ethylidene-beta-D-glucos-aminyl)-4-epi-podophyllotoxin (compound 15) The title compound wa~ prepared starting from 110 mg (0.18 mmol) of compound 13 by the procedure for the preparation of compound 14. Yield: 95 mg (75%)
Claims (11)
1. A process for the preparation of a glucosaminyl-epi-podophyllotoxin derivative of the formula I
I
in which R1 is hydrogen or the acetyl or a mono-, di- or trihaloyenoacetyl protective group with halogen being fluorine, chlorine or bromine, R2 is hydrogen or (C1-C4)-alkyl, R3 is hydrogen, (C1-C4)-alkyl or the benzyloxy-carbonyl protective group, R4 is hydrogen, a mono-, di- or trihalogenoacetyl protective group, a benzyloxycarbonyl protective group or a methyl group, and A is C1-C4 alkyl, which comprises reacting a glucosamine derivative of the formula II, which is in the alpha hydroxy form, II
in which R1 and R3 are acyl protective groups as defined above, and R2 is hydrogen and A is C1-C4-alkyl, with a podophyllotoxin derivative of the formula III
III
in which R4 is a methyl group or a mono-, di- or trihalogeno-acatyl or benzyloxycarbonyl protective group, in the presence of a promoter such as BF3 ether or of a tri-(C1-C4)-alkylsilyl trifluoromethanesulfonate and of an anhydrous organic solvent at -50°C to 20°C to give a 4-0-(beta-glucosaminyl)-epi-podophyllotoxin derivative of the formula I in which the radicals R1, R2, R3, R4 and A retain their meaning as defined above, subsequently eliminating the benzyloxycarbonyl pro-tective group by hydrogenolysis using a palladium catalyst, eliminating the acetyl protective group using zinc dichloride or diacetate and eliminating the halogenoacetyl protective groups using a basic anion exchanger in an organic solvent such as methan-ol, ethanol, acetone, ethyl acetate or mixtures thereof with water where appropriate, and, where appropriate, reacting the free amino group under the conditions of reductive alkylation with a C1-C4-aldehyde in the presence of a hydride to give a mono-or dialkylamino derivative, there being formation of a 4-O-(beta-glucosaminyl)-epi-podophyllotoxin deriva-tive of the formula I in which R1 is hydrogen, R2 and R3 are hydrogen or (C1-C4)-alkyl, R4 is hydrogen or the methyl group and A is C1-C4-alkyl.
I
in which R1 is hydrogen or the acetyl or a mono-, di- or trihaloyenoacetyl protective group with halogen being fluorine, chlorine or bromine, R2 is hydrogen or (C1-C4)-alkyl, R3 is hydrogen, (C1-C4)-alkyl or the benzyloxy-carbonyl protective group, R4 is hydrogen, a mono-, di- or trihalogenoacetyl protective group, a benzyloxycarbonyl protective group or a methyl group, and A is C1-C4 alkyl, which comprises reacting a glucosamine derivative of the formula II, which is in the alpha hydroxy form, II
in which R1 and R3 are acyl protective groups as defined above, and R2 is hydrogen and A is C1-C4-alkyl, with a podophyllotoxin derivative of the formula III
III
in which R4 is a methyl group or a mono-, di- or trihalogeno-acatyl or benzyloxycarbonyl protective group, in the presence of a promoter such as BF3 ether or of a tri-(C1-C4)-alkylsilyl trifluoromethanesulfonate and of an anhydrous organic solvent at -50°C to 20°C to give a 4-0-(beta-glucosaminyl)-epi-podophyllotoxin derivative of the formula I in which the radicals R1, R2, R3, R4 and A retain their meaning as defined above, subsequently eliminating the benzyloxycarbonyl pro-tective group by hydrogenolysis using a palladium catalyst, eliminating the acetyl protective group using zinc dichloride or diacetate and eliminating the halogenoacetyl protective groups using a basic anion exchanger in an organic solvent such as methan-ol, ethanol, acetone, ethyl acetate or mixtures thereof with water where appropriate, and, where appropriate, reacting the free amino group under the conditions of reductive alkylation with a C1-C4-aldehyde in the presence of a hydride to give a mono-or dialkylamino derivative, there being formation of a 4-O-(beta-glucosaminyl)-epi-podophyllotoxin deriva-tive of the formula I in which R1 is hydrogen, R2 and R3 are hydrogen or (C1-C4)-alkyl, R4 is hydrogen or the methyl group and A is C1-C4-alkyl.
2. The process as claimed in claim 1, in which R1 is hydrogen or the acetyl or a chloroacetyl protective group, R2 is hydrogen or (C1-C4)-alkyl, R3 is hydrogen, (C1-C4)-alkyl or the benzyloxycar-bonyl protective group, R4 is hydrogen, methyl or benzyloxycarbonyl or chloroacetyl protective groups and A is methyl, wherein a glucosamine derivative of the formula II
which is in the alpha-hydroxy form and in which R1 is a chloroacetyl group, R2 is a hydrogen atom, R3 is a benzyloxycarbonyl group and A is a methyl group is reacted with a podophyllotoxin derivative of the formula III in which R4 is a methyl group, chloroacetyl or benzyloxycar-bonyl protective group, in the presence of BF3.ether or tri-(C1-C4)-alxylsilyl trifluoromethanesulfonate in an organic solvent at -30°C to -10°C to give a 4-O-(beta-glucosaminyl)-epi-podophyllotoxin derivative of the formula I, and the compound is used for the preparation of another compound of the formula I.
which is in the alpha-hydroxy form and in which R1 is a chloroacetyl group, R2 is a hydrogen atom, R3 is a benzyloxycarbonyl group and A is a methyl group is reacted with a podophyllotoxin derivative of the formula III in which R4 is a methyl group, chloroacetyl or benzyloxycar-bonyl protective group, in the presence of BF3.ether or tri-(C1-C4)-alxylsilyl trifluoromethanesulfonate in an organic solvent at -30°C to -10°C to give a 4-O-(beta-glucosaminyl)-epi-podophyllotoxin derivative of the formula I, and the compound is used for the preparation of another compound of the formula I.
3. The process as claimed in claim 1 in which Rl is the acetyl or a mono-, di- or trihalogeno-acetyl protective group with halogen being fluorine, chlorine or bromine, R2 is a hydrogen atom, R3 is a benzyloxycarbonyl protective group, R4 is a mono-, di- or trihalogenoacetyl or benzyl-oxycarbonyl protective group or methyl group and A is C1-C4-alkyl, wherein a glucosamine derivative of the formula II
which is in the alpha form and in which R1, R2, R3 and A are as defined above is reacted with a podophyllo-toxin derivative of tha formula III in which R4 is as defined above, in the presence of a promoter such as BF3.ether or a tri-(C1-C4)-alkylsilyl trifluoromethane-sulfonate and of an anhydrous organic solvent at -50°C to + 20°C, preferably at -20°C to -30°C, whereappropriate with the addition of a drying agent such as a molecular sieve.
which is in the alpha form and in which R1, R2, R3 and A are as defined above is reacted with a podophyllo-toxin derivative of tha formula III in which R4 is as defined above, in the presence of a promoter such as BF3.ether or a tri-(C1-C4)-alkylsilyl trifluoromethane-sulfonate and of an anhydrous organic solvent at -50°C to + 20°C, preferably at -20°C to -30°C, whereappropriate with the addition of a drying agent such as a molecular sieve.
4. The process as claimed in claim 3, in which BF3.ether is employed as promoter.
5. The process as claimed in claim 3, in which ethyl acetate or a mixture thereof with another solvent such as dichloromethane, acetone or ether is used as organic solvent.
6. A process for the preparation of a glucosamine deriv-ative of the formula II which is in the alpha form and in which R1 is an acyl protective group R2 is hydrogen R3 is benzyloxycarbonyl protective group and A is C1-C4-alkyl which comprises treating a 1,3-di-0-acyl-4,6-0-alkyl-idene-2-N-benzyloxycaxbonyl-alpha,beta-D-glucosamiine derivative of the formula IV
IV
in which R1 and R5 are an acyl protective group as defined above, R2 is hydrogen, R3 is the benzyloxycarbonyl protective group and A is C1-C4-alkyl with an organic base such as piperidine or pyridine or with silica gel in a polar solvent such as methanol or ethanol, resulting in a compound of the formula II.
IV
in which R1 and R5 are an acyl protective group as defined above, R2 is hydrogen, R3 is the benzyloxycarbonyl protective group and A is C1-C4-alkyl with an organic base such as piperidine or pyridine or with silica gel in a polar solvent such as methanol or ethanol, resulting in a compound of the formula II.
7. A 3-0-acyl-4,6-0-alkylidene-2-N-benzyloxycarbonyl-alpha-D-glucosamine derivative of the formula II in which R1 is acetyl or mono-, di- or trihalogenoacetyl with halogen being fluorine, chlorine or bromine and A is C1-C4-alkyl.
8. A derivative as claimed in claim 7, in which R1 is the acetyl or chloroacetyl protective group and A is methyl.
9. 4-0-(4,6-0-Alkylidene-beta-D-glucosaminyl)-4-epi-podophyllotoxin of the formula I in claim 1 with A
C1-C4-alkyl.
C1-C4-alkyl.
10. 4-0-(4,6-0-Alkylidene-2-N-dimethyl-beta-D-glucosamin-yl)-4-epi-podophyllotoxin of the formula I in claim 1 with A C1-C4-alXyl.
11. The process as claimed in claim 1 and substantially as described herein.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEP3913327.3 | 1989-04-22 | ||
DE3913327A DE3913327A1 (en) | 1989-04-22 | 1989-04-22 | METHOD FOR PRODUCING GLUCOSAMINYL-EPI-PODO-PHYLLOTOXIN DERIVATIVES |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2015072A1 true CA2015072A1 (en) | 1990-10-22 |
Family
ID=6379258
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002015072A Abandoned CA2015072A1 (en) | 1989-04-22 | 1990-04-20 | Process for the preparation of glucosaminyl-epi-podophyllotoxin derivatives |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP0394908A1 (en) |
JP (1) | JPH02295996A (en) |
KR (1) | KR900016245A (en) |
AU (1) | AU643433B2 (en) |
CA (1) | CA2015072A1 (en) |
DE (1) | DE3913327A1 (en) |
PT (1) | PT93800A (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3913326A1 (en) * | 1989-04-22 | 1990-11-08 | Behringwerke Ag | METHOD FOR PRODUCING ETOPOSIDES |
ES2191733T3 (en) * | 1995-12-04 | 2003-09-16 | Nippon Kayaku Kk | PROCEDURE TO PRODUCE ETOPOSIDE. |
KR100418183B1 (en) * | 2000-01-03 | 2004-02-11 | 한국화학연구원 | 4-o-[2-(n,n-dialkylamino)-2-deoxy-4,6-o,o-(alkenylidene- or alkynylidene)-beta-d-glucosyl]-4'-o-demethyl-epi-podophyllotoxins, preparation thereof and antitumor composition containing same |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6032799A (en) * | 1983-07-29 | 1985-02-19 | Microbial Chem Res Found | Novel 4'-demethyl-4-epipodophyllotoxin derivative |
JPS61227590A (en) * | 1985-04-02 | 1986-10-09 | Microbial Chem Res Found | Novel 4'-epopodophyllotoxin derivative |
-
1989
- 1989-04-22 DE DE3913327A patent/DE3913327A1/en not_active Withdrawn
-
1990
- 1990-04-19 PT PT93800A patent/PT93800A/en not_active Application Discontinuation
- 1990-04-20 CA CA002015072A patent/CA2015072A1/en not_active Abandoned
- 1990-04-20 JP JP2103209A patent/JPH02295996A/en active Pending
- 1990-04-20 KR KR1019900005534A patent/KR900016245A/en not_active Application Discontinuation
- 1990-04-23 EP EP90107638A patent/EP0394908A1/en not_active Withdrawn
- 1990-04-23 AU AU53714/90A patent/AU643433B2/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
DE3913327A1 (en) | 1990-10-25 |
AU5371490A (en) | 1990-10-25 |
AU643433B2 (en) | 1993-11-18 |
KR900016245A (en) | 1990-11-13 |
PT93800A (en) | 1990-11-20 |
EP0394908A1 (en) | 1990-10-31 |
JPH02295996A (en) | 1990-12-06 |
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