title: Effective enzymatic caffeoylation of natural glucopyranosides.
abstract: Reaction system was developed for enzymatic caffeoylation of model saccharidic acceptor methyl β-d-glucopyranoside to obtain exclusively methyl 6-O-caffeoyl-β-D-glucopyranoside. Reaction with starting concentration of acceptor 0.2 M provided 73% yield of purified product within 17 days. Reactions with low acceptor concentrations (0.04 and 0.08 M) run to the completion within 7 days. Such highly effective and regioselective reaction was promoted by Lipozyme TL IM in tert-butanol, using vinyl caffeate as acylation donor. The optimized reaction conditions were used in preparative caffeoylation of natural substances-arbutin and salidroside, giving 75% of 6-O-caffeoylated arbutin (robustaside B) and 74% of 6-O-caffeoylated salidroside as the only products after 12 and 16 days, respectively.
authors.affiliation: Laboratory of Biocatalysis and Organic Synthesis, Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 38 Bratislava, Slovakia.
authors.forename: Andrej
authors.initials: A
authors.lastname: Chyba
authors.affiliation: Laboratory of Biocatalysis and Organic Synthesis, Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 38 Bratislava, Slovakia.
authors.forename: Vladimír
authors.initials: V
authors.lastname: Mastihuba
authors.affiliation: Laboratory of Biocatalysis and Organic Synthesis, Institute of Chemistry, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 38 Bratislava, Slovakia. Electronic address: chemjama@savba.sk.
authors.forename: Mária
authors.initials: M
authors.lastname: Mastihubová
mesh_terms: D001688:Biological Products / Q000737:chemistry / Q000378:metabolism*; D002109:Caffeic Acids / Q000737:chemistry / Q000378:metabolism*; D005960:Glucosides / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism*; D008049:Lipase / Q000378:metabolism*; D015394:Molecular Structure; D011714:Pyrans / Q000737:chemistry / Q000378:metabolism*
chemical_list: D001688:Biological Products; D002109:Caffeic Acids; D005960:Glucosides; D011714:Pyrans; C093666:Lipozyme; D008049:Lipase
keywords: 6-O-Caffeoyl-salidroside; Lipozyme TL IM; Phenylpropanoid glycosides; Regioselective caffeoylation; Robustaside B