Structure-activity relationships for interactions between carbapenems and beta-lactamases

Synthesis and biological activities of an alpha-methyl and a beta-methyl carbapenem and the corresponding unsubstituted compound

The carbapenem potassium salts 4, 7 and 8 were prepared. Their rates of beta-lactam hydrolysis and their biological activities, particularly their beta-lactamase inhibiting properties, were examined and explained on the basis of their different substitution and pyramidality.

Synthesis and biological properties of new 1 beta-methylcarbapenems

The synthesis and biological activity of the novel series of 1 beta-methylcarbapenems, 1 and 2 were described. Most compounds displayed high potent antibacterial activity. The best compound in this series, 2a (IH201; R2 = NH2) showed an excellent and a broad spectrum as well as high renal DHP-I stability. It also possessed good in vivo efficacy and high safety.

Structural comparison of 1 beta-methylcarbapenem, carbapenem and penem: NMR studies and theoretical calculations

Structural comparisons of meropenem (1), desmethyl meropenem (2) and the penem analogue (3) which contain the same side chains at both C-2 and C-6 were performed using 1H NMR measurements together with 3-21G* level of ab initio MO and molecular mechanics calculations. The ab initio MO calculations reproduced the skeletons of these strained beta-lactam rings in good agreement with the crystallographic data. 1H NMR measurements in aqueous solution together with molecular modeling studies indicated that there were conformational differences of the C-2 and C-6 side chains in this series of compounds. These observations suggested that the conformational differences could affect their biological activities.