Biosynthesis Of Coumarin Glycosides By Transgenic Hairy Roots Of Polygonum Multiflorum

To investigate the substrate specificity and regioselectivity of coumarin glycosyltransferases in transgenic hairy roots of Polygonum mulhflorum, esculetin (1) and eight hydroxycoumarins (2-9) were employed as substrates. Nine corresponding glycosides (10-18) involving four new compounds, 6-chloro-4-methylcoumarin 7-O-beta-o-glucopyranoside (15), 6-chloro-4-phenylcoumarin 7-O-beta-D-glucopyranoside (16), 8-hydroxy-4-methylcoumarin 7-O-beta-D-glucopyranoside (17), and 8-allyl-4-methylcoumarin 7-O-beta-D-glucopyranoside (18), were biosynthesized by the hairy roots.