Abstract: Novel 2,3,4,5-tetrahydro-1H-3-benzazepines having the formula ##STR1## wherein R.sup.3 represents H, C.sub.1-3 -alkyl or C.sub.3-7 -cycloalkyl; R.sup.4 represents hydrogen or R.sup.4 together with R.sup.10 represents a bridge which connects the positions to which R.sup.4 and R.sup.10 are linked, said bridge being --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --O--CH.sub.2 -- or --S--CH.sub.2 --;R.sup.7 represent hydroxy, lower alkoxy;R.sup.10, R.sup.11, R.sup.12 independently represent hydrogen or halogen or alkyl or alkoxy or trifluoromethyl, or R.sup.10 together with R.sup.4 represents a bridge as described in connection with the definition of R.sup.4 ; or R.sup.10 together with R.sup.11 represents a bridge or R.sup.11 together with R.sup.12 represents a bridge, the bridge in both cases being chosen among --O--CH.sub.2 --CH.sub.2 --, --O--CH.sub.2 --CH.sub.2 --CH.sub.2 --, --O-CH.dbd.CH--, --CH.sub.2 -CH.sub.2 -CH.sub.2 --, --CH.sub.2 -CH.dbd.CH-- or --CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --;R.sup.

Abstract: New derivatives of penem and pharmaceutically acceptable salt thereof are herein disclosed; these compounds being useful as an antibacterial agent which has an extremely wide antibacterial spectrum, exhibits a high sensitivity to bacteria resistant to conventional penicillins and cephalosporing antibiotics and is excellent in its physico-chemical stability, solubility to water and biological stability, in particular, stability to decomposition by enzyme such as dehydropeptidase I in kidney, .beta.-lactamase; these derivatives of penem being able to be prepared by reacting 2-substituted sulfinyl derivative of penem with a thiol compound and then optionally removing protective group(s) and further alkylating the reaction product or vice versa.