Nitrile oxides in medicinal chemistry .6. Enzymatic resolution of a set of bicyclic Delta(2)-isoxazolines.

Chymotrypsin selectively catalyzed the hydrolysis of a series of 3-ethoxycarbonyl-Delta(2)-isoxazolines 1-4, whereas lipase from Pseudomonas cepacia (lipase PS) was remarkably selective in hydrolysing the corresponding 3-hydroxymethyl-Delta(2)-isoxazoline butyrates (5-8). The enantio-preference of chymotrypsin for the first set of compounds is the same as that observed for the lipase PS-cataiyzed hydrolysis of the other series of substrates. The hydrolytic activity of lipase PS for compounds 5-8 was considerably higher than that shown by chymotrypsin for substrates 1-4. (C) 1996 Elsevier Science Ltd