Synthesis and antibacterial activity of 2-(isoxazolidinio-5-yl)carbapenem derivatives.

The synthesis and antibacterial activity of the title compounds having an isoxazolidine ring at the C-2 position are described. These derivatives were synthesized by the 1,3-dipolar cycloaddition reaction of nitrone with 2-vinyl carbapenems. This 1,3-dipolar cycloaddition reaction proceeded regioselectively to give diastereomeric isomers of 2(-isoxazolidin-5-yl)carbapenems. It was ascertained that the antibacterial activity of 1 beta-methylcarbapenem derivatives was superior to that of the corresponding 1H-carbapenem derivatives, and between the 2-(isoxazolidin-5-yl)-1 beta-methylcarbapenems the antibacterial activity of the 5'R-isomer was slightly better than that of the 5' R-isomer slightly better than that of the 5' S-isomer.