Orally active carbapenem antibiotics I. Antibacterial and pharmacokinetic potential of 2-phenyl and 2-thienylcarbapenems.

In order to design orally active carbapenem antibiotics effective against /5-lactam-resistant pathogens, such as penicillin-resistant Streptococcus pneumoniae (PRSP) and β-lactamase non-producing ampicillin-resistant Haemophilus influenzae (BLNAR), a series of novel 2-phenylcarbapenems and some 2-thienyl derivatives were synthesized and tested for antibacterial activities. These compounds were highly active against PRSP, BLNAR, and major Gram-positive and Gram-negative bacteria that cause community-acquired infections. Their pivaloyloxymethylester-type prodrug exhibited good oral absorption in mice, suggesting that this series of carbapenems were promising as a prototype of novel orally active β-lactams.