| abstract |
Beta-lactam antibiotics corresponding to formula (I) or one of their salts. In the formula, R4 represents hydrogen, methoxy or formamido; R2 represents an acyl group; CO2R3 represents a carboxy group or a carboxylate anion, or R3 represents an easily removable carboxy protection group; R4 represents up to four substituents; X represents S, SO, SO2, O or CH2; m is 1 or 2; and n is 0, effective in the treatment of bacterial infections in humans and animals. |