title: Bioreduction of alpha-methylcinnamaldehyde derivatives: chemo-enzymatic asymmetric synthesis of Lilial and Helional.
abstract: Nonracemic aryl-substituted alpha-methyldihydrocinnamaldehyde derivatives employed as olfactory principles in perfumes (Lilial, Helional) were obtained via enzymatic reduction of the corresponding cinnamaldehyde precursors using cloned and overexpressed ene-reductases. (R)-Enantiomers were obtained using the old-yellow-enzyme (OYE) homolog YqjM from Bacillus subtilis and 12-oxophytodienoic acid reductase isoenzyme OPR1 from tomato (e.e.(max) 53%), and (S)-aldehydes were furnished in up to 97% e.e. using isoenzyme OPR3, nicotinamide 2-cyclohexene-1-one reductase NCR from Zymomonas mobilis and yeast OYE isoenzymes 1-3 under optimised reaction conditions in the presence of t-butyl methyl ether as the co-solvent. The stereochemical outcome of the reduction of alpha-methylcinnamaldehyde using NCR and OYEs 1-3 [previously reported to be (R)] was unambiguously corrected to be (S).
authors.affiliation: Department of Chemistry, Organic & Bioorganic Chemistry, Heinrichstrasse 28, A-8010, Graz, Austria.
authors.forename: Clemens
authors.initials: C
authors.lastname: Stueckler
authors.forename: Nicole J
authors.initials: NJ
authors.lastname: Mueller
authors.forename: Christoph K
authors.initials: CK
authors.lastname: Winkler
authors.forename: Silvia M
authors.initials: SM
authors.lastname: Glueck
authors.forename: Karl
authors.initials: K
authors.lastname: Gruber
authors.forename: Georg
authors.initials: G
authors.lastname: Steinkellner
authors.forename: Kurt
authors.initials: K
authors.lastname: Faber
mesh_terms: D000171:Acrolein / Q000031:analogs & derivatives* / Q000737:chemistry; D000447:Aldehydes / Q000737:chemistry / Q000378:metabolism*; D001412:Bacillus subtilis / Q000201:enzymology; D001426:Bacterial Proteins / Q000378:metabolism; D001665:Binding Sites; D055162:Biocatalysis; D004798:Enzymes / Q000378:metabolism*; D005656:Fungal Proteins / Q000378:metabolism; D018551:Solanum lycopersicum / Q000201:enzymology; D008958:Models, Molecular; D009252:NADPH Dehydrogenase / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000378:metabolism; D010476:Perfume / Q000737:chemistry / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism; D013237:Stereoisomerism; D017355:Zymomonas / Q000201:enzymology
chemical_list: D000447:Aldehydes; D001426:Bacterial Proteins; D004798:Enzymes; D005656:Fungal Proteins; D010476:Perfume; D010940:Plant Proteins; D000171:Acrolein; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; C117248:2-cyclohexen-1-one reductase (NAD(P)H); C106360:12-oxophytodienoate reductase; D009252:NADPH Dehydrogenase; C012843:cinnamaldehyde; C038018:lilial