Abstract
(5S) -Tricyclic penems were synthesized
for the first time via intramolecular cyclization of penem epoxy
amides catalyzed by a weak Lewis acid [Mg(ClO4 )2 ].
Due to the high degree of ring strain in these molecules, mild reaction
conditions were developed to successfully construct penem intermediates
and the tricyclic penem final products. These tricyclic penems and
other newly synthesized (5S )-penem esters
and amides exhibited good-to-high potency when tested as inhibitors
of bacterial signal peptidases.
Key words
tricyclic penems - β-lactams - cyclization - epoxidation - signal peptidase - inhibitors
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