| 摘要 |
<p>Penam 1,1 -dioxides of the formula: …<CHEM>… and the pharmaceutically-acceptable base salts thereof, wherein R<1> is selcted from hydrogen, ester-forming residues readily hydrolyzable in vivo, and conventional carboxy protecting groups; and R<2> and R<3> are each hydrogen or methyl provided they are not both methyl. The compounds in which R<1> is hydrogen or an ester-forming residue readily hydrolyzable in vivo are useful for enhancing the antibacterial activity of beta -lactam antibiotics; those in which R<1> is a conventional carboxy-protecting group are useful intermediates.</p> |
