| 摘要 |
Antibiotic activity is exhibited by beta -lactams having an <IMAGE> substituent in the 1-position and an acylamino substituent in the 3- position, R<5> and R<6> being hydrogen atoms at various defined substituents or R<5> and R<6> together completing a ring. The corresponding 3-amino compounds may be produced as intermediates. The compounds may be of the formula:- <IMAGE> or salts or esters thereof, R1 being hydrogen or acyl and R2, R3 and R4 being hydrogen atoms or substituents. |
