Synthesis and structure-activity relationships of 2-azetidinone-1-sulfonic acid derivatives with a heteroatom-bound substituent at the 4-position.

The synthesis and antibacterial activity of 3-[(Z)-2-alkoxyimino-2-(2-aminothiazol-4-yl)-acetamido] -2-azetidinone-1-sulfonic acid derivatives with a heteroatom-bound substituent at the 4-position are described. The effect of various 4-substituents on the antibacterial activity was examined. Some of these compounds showed excellent antibacterial activity especially against Gram-negative bacteria, including beta-lactamase-producing strains.