| abstract |
There is disclosed an azetidinones compound of the formula (I): Wherein, R is hydrogen, or hydroxy protecting group, R 1 and R 2 are each independently alkyl of 1-15 carbon atoms, benzyl or cycloalkyl of 5-6 carbon atom which may have substituent(s), R 3 is low alkyl, or low alkyl ester, R 4 is aryl, or aryl substituted with halogen, alkoxy of 1-6 carbon atom, nitro groups which is useful as a synthetic intermediate of the 1′β-methylcarbapenem-type antibacterial agent. |