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Patent EP0195960A1 successfully refreshed from Google Patents.
EP0195960A1
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EP
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Method for selective methylation of erythromycin a derivatives
Assignee: Taisho Pharmaceutical Co Ltd
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Filing: 1986-03-05
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Granted: —
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Expires: 2006-03-05
Abstract
Abstract A method for the selective methylation of the hydroxy group at the 6-position of erythromycin A derivatives which comprises reacting a compound represented by the formula R-X (wherein R is a 2-alkenyl group, a benzyl group or a substituted benzyl group, and X is a halogen atom), reacting the resulting quaternary salt compound with a methylating agent, and then eliminating R groups of the resulting compound to give 6-0-methylerythromycin A 9-oxime, is disclosed.
Inventors
- 👤 Shigeo Morimoto
- 👤 Takashi Adachi
- 👤 Toshifumi Asaka
- 👤 Masato Kashimura
- 👤 Yoshiaki Watanabe
- 👤 Kaoru Sota
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 07:14
CPC Classifications
C; C07; C07H; C07H17/00; C07H17/04; C07H17/08; A; A61; A61K; A61K31/00; A61K31/70; A61K31/7042; A61K31/7048
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
102 words
A method for the selective methylation of the hydroxy group at the 6-position of erythromycin A derivatives which comprises reacting erythromycin A 9-oxime with a compound represented by the formula R-X (wherein R is a 2-alkenyl group, a benzyl group or a substituted benzyl group, and X is a halogen atom) to give a quaternary salt compound represented by the formula (wherein R and X are as defined above), reacting the resulting compound with a methylating agent to give a 6-0-methylerythromycin A derivative, and eliminating R groups of the resulting compound by hydrogenolysis to give 6-0-methylerythromycin A 9-oxime represented by the formula
Claim 2
Independent Claim
102 words
A method for the selective methylation of the hydroxy group at the 6-position of erythromycin A derivatives which comprises reacting erythromycin A 9-oxime with a compound represented by the formula R-X (wherein R is a 2-alkenyl group, a benzyl group or a substituted benzyl group, and X is a halogen atom) to give a quaternary salt compound represented by the formula (wherein R and X are as defined above), reacting the resulting compound with a methylating agent to give a 6-0-methylerythromycin A derivative, and eliminating R groups of the resulting compound by hydrogenolysis to give 6-0-methylerythromycin A 9-oxime represented by the formula
Claim 3
Dependent Claim
15 words
A method according to Claim 1, wherein the compound of R-X is an allyl halide
Claim 4
Dependent Claim
15 words
A method according to Claim 1, wherein the compound of R-X is a benzyl halide.
References Cited (Backward Citations)
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