EP0147062A2
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EP
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Method for preparing 6-0-methyl-2'-0,N-Bis (Benzyloxycarbonyl)-n-Demethylerythromycin a.
Assignee: Taisho Pharmaceutical Co Ltd
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Filing: 1984-11-26
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Granted: —
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Expires: 2004-11-26
Abstract
Abstract A method for preparing 6-O-methyl-2 min -O,N-bis (benzyloxycarbonyl)-N-demethylerythromycin A comprises methylating 2 min -O,N-bis(benzyloxycarbonyl)-N-demethylerythromycin A with a methylating agent in the presence of potassium hydroxide or sodium hydroxide in a polar aprotic solvent.
Inventors
- 👤 Shigeo Morimoto
- 👤 Takashi Adachi
- 👤 Yoko Takahashi
- 👤 Yoshiaki Watanabe
- 👤 Kaoru Sota
- 👤 Yasuo Kikugawa
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 10:08
CPC Classifications
C; C07; C07H; C07H17/00; C07H17/04; C07H17/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
32 words
A method for preparing 6-0-methyl-2'-0,N-bis (benzyloxycarbonyl)-N-demethylerythromycin A which comprises methylating 2'-0,N-bis(benzyloxycarbonyl)- N -demethylerythromycin A with a methylating agent in the presence of potassium hydroxide or sodium hydroxide in a polar aprotic solvent.
Claim 2
Independent Claim
32 words
A method for preparing 6-0-methyl-2'-0,N-bis (benzyloxycarbonyl)-N-demethylerythromycin A which comprises methylating 2'-0,N-bis(benzyloxycarbonyl)- N -demethylerythromycin A with a methylating agent in the presence of potassium hydroxide or sodium hydroxide in a polar aprotic solvent.
Claim 3
Dependent Claim
24 words
A method according to Claim 1, wherein the methylating agent is methyl iodide, methyl bromide, methyl chloride, dimethyl sulfate, methyl p-toluenesulfonate, or methyl methanesulfonate.
Claim 4
Dependent Claim
13 words
A method according to Claim 2, wherein the methylating agent is methyl iodide.
Claim 5
Dependent Claim
46 words
A method according to Claim 1, 2 or 3, wherein the polar aprotic solvent is dimethyl sulfoxide alone or a mixture of dimethyl sulfoxide with dimethoxymethane, 1,2-dimethoxyethane, tetrahydrofuran, dioxane, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, acetonitrile, dichloromethane, 1',2-dichloroethane, N,N-dimethyliformamide, tetramethylene sulfoxide or hexamethylphosphoric triamide.
Claim 6
Dependent Claim
22 words
A method according to Claim 4, wherein the polar aprotic solvent is dimethyl sulfoxide or a mixture of dimethyl sulfoxide and 1,2-dimethoxyethane.
Claim 7
Independent Claim
23 words
A method according to any preceding Claim, wherein the amount of methylating agent is 1 to 8 molar equivalents relative to 2'-O,N-bis(benzyloxycarbonyl)-N-demethylerythromycin A.
Claim 8
Independent Claim
26 words
A method according to any preceding Claim, wherein the amount of potassium hydroxide or sodium hydroxide is 0.9 to 1.3 molar equivalents relative to 2'-O,N-bis(benzyloxycarbonyl)-N-demethylerythromycin A.
Claim 9
Independent Claim
22 words
A method according to any preceding Claim, wherein the methylation is conducted at 0°C to room temperature for 2 to 5 hours.
Claim 10
Independent Claim
41 words
A method according to any preceding Claim which includes the additional step of removing the said benzyloxycarbonyl groups from the 2'-0 and N-positions of the 6-0-methyl-2'-O,N-bis (benzyloxycarbonyl)-N-demethy- lerythromycin A, and methylating the resultant product at the N-position to give 6-0-methylerythromycin A.
References Cited (Backward Citations)
No citation records indexed.
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