| 摘要 |
<p>1316689 Rifamycin SV derivatives GRUPPO LEPETIT SpA 15 Dec 1971 [18 Jan 1971] 58329/71 Heading C2A Novel rifamycin SV derivatives having the general formula wherein R and R<SP>1</SP> each represent a C 1 -C 8 alkyl, C 3 -C 8 alkenyl, cycloalkyl, aryl, cycloalkyl-(C 1 -C 8 ) alkyl or aryl-(C 1 -C 5 ) alkyl group, or taken together with the common nitrogen atom form a heterocycle which may contain other hetero atoms and/or be substituted by C 1 -C 4 alkyl or C 1 -C 4 carbalkoxy, are prepared by reacting one molecular amount of rifamycin O with two molcular amounts of an amine of formula in which R and R<SP>1</SP> are as defined above, in an organic solvent at 15‹ to 35‹ C. The aryl group is preferably phenyl which may be substituted by alkyl, alkoxy or halogen. The heterocycle is preferably a saturated 5 to 8 membered ring. The reaction product is recovered by evaporating the solvent and taking up the residue in a solvent (e.g. ethyl acetate), from which it is recrystallized or precipitated by adding a non-solvent (e.g. hexane). Pharmaceutical compositions having antibiotic activity comprises the aforesaid rifamycin SV derivative and a pharmaceutically acceptable carrier.</p> |
