| abstract |
A compound of general formula (I) in which R is (a); wherein Rα is hydrogen, optionally substituted (C¿1-6?)alkyl or optionally substituted aryl; R?β¿ is hydrogen, optionally substituted (C¿1-6?)alkyl or optionally substituted aryl; or R?α and Rβ¿ together form an optionally substituted 5 or 6 membered heterocyclic ring with or without additional heteroatoms; R1 is (C¿1-6?)alkyl which is unsubstituted or substituted by fluoro, a hydroxy group which is optionally protected by a readily removable hydroxy protecting group, or by an amino group which is optionally protected by a readily removable amino protecting group; R?2¿ is hydrogen or methyl; and R3 is selected from the group consisting of (a) a group of formula (i) wherein R¿1? is hydrogen or (C1-6)alkyl, R2 is hydrogen, (C1-6)alkyl optionally substituted by halogen, (C1-6)alkenyl, (C1-6)alkoxycarbonyl, aryl, or heteroaryl, R3 is hydrogen, (C1-6)alkyl, or (C1-6)alkoxycarbonyl, and R4 is a pharmaceutically acceptable ester forming group, and (b) a group of formula CH(R?a)O.CO.Rb¿, wherein Ra is hydrogen, (C¿1-6?)alkyl, (C3-7)cycloalkyl, methyl, or phenyl; and R?b¿ is (C¿1-6?)alkyl(C3-7)cycloalkyloxy or (C1-6)alkoxy(C1-6)alkyl, is useful in the treatment of bacterial infections. |