title: Enantioselective esterification of racemic naproxen by lipases in organic solvent.
abstract: Enantioselective esterification of naproxen, 2-(6-methoxy-2-naphthyl) propionic acid, was attempted by lipases in nearly anhydrous isooctane. The nature of the alcohol affects the reactivity and enantioselectivity of the lipase from Candida cylindracea. Alcohols containing a trimethylsilyl group are highly reactive and enantioselective to the S-isomer of the acid. An optimal temperature around 65 degrees C and an enzyme concentration less than 7 mg ml-1 were proposed to resolve the racemate, with trimethylsilyl methanol as nucleophile, from a consideration of the enantiomeric ratio, the ester formation, and the resistance of mass transfer for the substrate.
authors.affiliation: Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan, Republic of China.
authors.forename: S W
authors.initials: SW
authors.lastname: Tsai
authors.forename: H J
authors.initials: HJ
authors.lastname: Wei
mesh_terms: D000438:Alcohols / Q000378:metabolism; D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D002175:Candida / Q000201:enzymology; D004951:Esterification; D005656:Fungal Proteins / Q000378:metabolism; D008049:Lipase / Q000378:metabolism*; D009288:Naproxen / Q000737:chemistry / Q000378:metabolism*; D009795:Octanes; D010940:Plant Proteins / Q000378:metabolism; D012997:Solvents; D013237:Stereoisomerism; D013379:Substrate Specificity; D013552:Swine; D013696:Temperature; D014297:Trimethylsilyl Compounds / Q000378:metabolism
chemical_list: D000438:Alcohols; D001426:Bacterial Proteins; D005656:Fungal Proteins; D009795:Octanes; D010940:Plant Proteins; D012997:Solvents; D014297:Trimethylsilyl Compounds; C086780:(trimethylsilyl)methanol; D009288:Naproxen; D008049:Lipase; C045798:2,2,4-trimethylpentane