Selective biotransformation reactions on (±)-aryl alkyl ketones, (±)-benzoxazines, and d-arabino- and d-threo-hydroxyalkyltriazoles

• Published in: Pure and Applied Chemistry
• Main Authors: Raunak, Prasad, Ashok K., Shakil, Najam A., Himanshu, Parmar, Virinder S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Walter de Gruyter GmbH 2001
• Subjects: General Chemical Engineering; General Chemistry; Rugosa; Antarc*; Antarctica
• Online Access: http://dx.doi.org/10.1351/pac200173010167; https://www.degruyter.com/view/journals/pac/73/1/article-p167.xml; https://www.degruyter.com/document/doi/10.1351/pac200173010167/xml; https://www.degruyter.com/document/doi/10.1351/pac200173010167/pdf

Abstract The capabilities of porcine pancreatic lipase (PPL), Candida antarctica lipase (CAL), and Candida rugosa lipase (CRL) were evaluated for enantio- and/or regioselective acetylation/deacetylation of (±)-2,4-diacetoxyphenyl alkyl ketones, (±)-4-alkyl-3,4-dihydro-3-hydroxyalkyl-2 H -1,3-benzoxazines, and d- arabino and d- threo -polyhydroxyalkyltriazoles in organic solvents. PPL in tetrahydrofuran (THF) exhibited high to moderate enantioselectivity during the deacetylation of (±)-2,4-diacetoxyaryl alkyl ketones and acetylation of (±)-3-hydroxyalkyl-2 H -1,3-benzoxazines. Together with enantioselectivity, PPL in THF also showed exclusive regioselectivity for the deacetylation of para -acetoxy over the ortho -acetoxy function, with respect to the nuclear carbonyl group in 2,4-diacetoxyphenyl alkyl ketones. CAL in diisopropyl ether (DIPE) and PPL in THF exhibited exclusive selectivity for the acetylation of primary hydroxyl over secondary hydroxyl group(s) of d- arabino - and d- threo -polyhydroxyalkyltriazoles.