An Efficient One-Pot Enzymatic Synthesis of Cardiac Glycosides with Varied Sugar Chain Lengths
An efficient one-pot enzymatic synthesis of cardiac glycosides with varied sugar chain lengths (average yield >80%) was carried out through sequential glycosylation using a steroid glycosyltransferase UGT74AN3 from Catharanthus roseus and a cyclodextrin glycosyltransferase from Bacillus licheniformis. A series of cardiac glycosides were obtained and showed enhanced affinity and selectivity for inhibition of the α2 isoform of Na+/K+-ATPase. These findings demonstrate the significant potential of the one-pot biocatalytic approach in the synthesis of diverse cardiac glycosides as potentially safer cardiotonic agents. (Figure presented.).
Huang, Wei,Wen, Chao,Zhou, Zhen-Ru,Fu, Zhi-Hao,Katz, Adriana,Plotnikov, Alexander,Karlish, Steven J. D.,Jiang, Ren-Wang
supporting information
p. 3114 - 3119
(2019/05/22)
Biotransformation of digitoxigenin by cultured Strophanthus hybrid cells
Hybrid cells between Strophanthus gratus and S. amboensis were obtained by electrofusion and confirmed to be hybrids through isozyme and RFLP analyses. Because a new and hybrid compound, 17βH-periplogenin β-D- glucoside, was isolated as a biotransformation product of digitoxigenin by the hybrid cells, isomerization of 17β-lactone ring on S. gratus and glucosylation on S. amboensis were demonstrated simultaneously as the biotransformation abilities in the hybrid cells. Moreover, the productivity of the hybrid compound was increased by raising the sucrose concentration.
Biotransformation of digitoxigenin by cultured ginseng cells
Nine compounds, including a new compound (digitoxigenin β-D-glucoside malonyl ester), were isolated as biotransformation products of digitoxigenin by cell suspension cultures of Panax ginseng (Pg-3 cell line). At the same time, two known products were identified by TLC and HPLC.
BIOTRANSFORMATION OF DIGITOXIGENIN BY GINSENG HAIRY ROOT CULTURES
Five new compounds (three esters and two glycosides) and seven previously reported compounds were isolated as biotransformation products of digitoxigenin by ginseng hairy root cultures.The new esters and glycosides were elucidated as digitoxigenin stearate, digitoxigenin palmitate, digitoxigenin myristate, 3-epidigitoxigenin β-D-gentiobioside and digitoxigenin β-D-sophoroside using 1H and 13C NMR and FAB mass spectral data.Biotransformations involving esterification (of stearic acid, palmitic acid, myristic acid and lauric acid) and glycosylation (of gentiobiose and sophorose) of digitoxigenin have been demonstrated for the first time in the plant cell and tissue cultures.The hairy roots showed high glycosylation ability to the digitoxigenin molecule.