EP0161534A2 — New process for the synthesis of pyrido-imidazo-refamycins
Assigned to Alfa Wasserman SpA · Expires 1985-11-21 · 40y expired
What this patent protects
A new process for the synthesis of pyrido-imidazo-rifamycins of formula wherein R is hydrogen or acetyl, R, and R 2 independently represent hydrogen, (C 1-4 )-alkyl, benzyloxy, mono- or di-(C 1-3 )-alkylamino-(C 1-4 )-alkyl. (C 1-3 )-alkoxy-(C 1-4 )-alkyl, hydroxymethyl, hy…
USPTO Abstract
A new process for the synthesis of pyrido-imidazo-rifamycins of formula wherein R is hydrogen or acetyl, R, and R 2 independently represent hydrogen, (C 1-4 )-alkyl, benzyloxy, mono- or di-(C 1-3 )-alkylamino-(C 1-4 )-alkyl. (C 1-3 )-alkoxy-(C 1-4 )-alkyl, hydroxymethyl, hydroxy-(C 2 - 4 )-alkyl, cyano, halogen, nitro, mercapto, (C 1-4 )-alkylthio, phenylthio, carbamoyl, mono- or di-(C 1-4 )-alkyl-carbamoyl, or R 1 and R 2 taken together with two consecutive carbon atoms of the pyridine nucleus form a benzene ring optionally substituted by one or two methyl or ethyl groups. The process comprises reacting the rifamycin 0 of (Continuation next page) with a 2-aminopyridine of formula wherein R 1 and R 2 have the same meanings as before.
Drugs covered by this patent
- Xifaxan (rifaximin) · Bausch Health
Bibliographic data sourced from FDA Orange Book + USPTO public records. Plain-English summary generated by AI grounded in source text. Patent term extensions (PTR, SPC, pediatric) may shift the effective expiry. Not legal advice.
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