title: Efficient biocatalytic synthesis of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol by a newly isolated Trichoderma asperellum ZJPH0810 using dual cosubstrate: ethanol and glycerol.
abstract: (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol is a crucial intermediate for the synthesis of Aprepitant. An efficient biocatalytic process for (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol was developed via the asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone, catalyzed by whole cells of newly isolated Trichoderma asperellum ZJPH0810 using ethanol and glycerol as dual cosubstrate for cofactor recycling. A fungal strain ZJPH0810, showing asymmetric biocatalytic activity of 3,5-bis(trifluoromethyl) acetophenone to its corresponding (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol, was isolated from a soil sample. Based on its morphological and physiological characteristics and internal transcribed spacer sequence, this isolate was identified as T. asperellum ZJPH0810, which afforded an NADH-dependent (R)-stereospecific carbonyl reductase and was a promising biocatalyst for the synthesis of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol. Some key reaction parameters involved in the bioreduction catalyzed by T. asperellum ZJPH0810 were subsequently optimized. The effectiveness of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol production was significantly enhanced by employing a novel dual cosubstrate-coupled system for cofactor recycling. The established efficient bioreduction system contained 50 mM of 3,5-bis(trifluoromethyl) acetophenone and 60 g l(-1) of resting cells, employing ethanol (6.0 %, v/v) and glycerol (0.5 %, v/v) as dual cosubstrate. The bioreduction was performed in distilled water medium, at 30 °C and 200 rpm. Under the above conditions, a best yield of 93.4 % was obtained, which is nearly a 3.5-fold increase in contrast to no addition of cosubstrate. The ee value of the product reached above 98 %. This biocatalytic process shows great potential in the production of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol, a valuable chiral building block in the pharmaceutical industry.
authors.affiliation: College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310032, People's Republic of China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Pu
authors.initials: P
authors.lastname: Wang
authors.forename: Jun-Yao
authors.initials: JY
authors.lastname: He
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.forename: Jun
authors.initials: J
authors.lastname: Tang
mesh_terms: D001483:Base Sequence; D001592:Benzyl Alcohols / Q000378:metabolism*; D055162:Biocatalysis; D017931:DNA Primers; D000431:Ethanol / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D013379:Substrate Specificity; D014242:Trichoderma / Q000145:classification / Q000378:metabolism*
chemical_list: D001592:Benzyl Alcohols; D017931:DNA Primers; D009243:NAD; D000431:Ethanol; D005990:Glycerol