Methods for the stereoselective cis-cyanohydroxylation and -carboxyhydroxylation of olefins
作者:Alan P. Kozikowski、Maciej Adamcz
DOI:10.1021/jo00151a017
日期:1983.2
Resolution of ?2-isoxazoline-5-carboxylates by a protease fromAspergillus Oryzae providing masked synthons for enantiopure ?-aminoalcohols and related structures
作者:S. Yang、W. Hayden、H. Griengl
DOI:10.1007/bf00811865
日期:1994.4
A series of racemic DELTA2-isoxazolinecarboxylates have been synthesized and subjected to enzymatic hydrolysis by a protease from Aspergillus oryzae in a two-phase system. Out of these compounds only isoxazoline-5-carboxylates unsubstituted at C-4 were hydrolyzed. Thus, from 3-ethoxycarbonyl-, 3-methyl-, and 3-phenyl-DELTA2-isoxazoline-5-carboxylates the corresponding (R)-configurated carboxylic acids are obtained. In contrast, an additional methyl group at C-5 changes the steric course of the hydrolysis to give predominantly the (S)-acid. The enantioselectivities obtained are in the range of E = 5-35.
Nitrile oxides in medicinal chemistry. 6. Enzymatic resolution of a set of bicyclic Δ2-isoxazolines
作者:Marco De Amici、Carlo De Micheli、Giacomo Carrea、Sergio Riva
DOI:10.1016/0957-4166(96)00075-4
日期:1996.3
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
Fajkos,J.; Edwards,J.A., Journal of Heterocyclic Chemistry, 1974, vol. 11, p. 63 - 67