The interaction of alkynyl carboxylates with serine enzymes a potent new class of serine enzyme inhibitors

The recently reported alkynyl esters, propynyl benzoate and propynyl p-methoxybenzoate, were found to interact with a variety of serine enzymes. α-Chymotrypsin was inhibited very rapidly by an equivalent amount of the esters. Trypsin, elastase and pronase were also inhibited by the esters. On the other hand, liver esterase started to hydrolyse the alkynyl esters rapidly, but the enzyme became inhibited during the course of reaction. The inhibited enzymes exhibited slow reactivation which could be considerably enhanced by hydroxylamine.