根据化学转化、1H和13C核磁共振谱,从黄合花中分离得到的dauroside D的结构已确定为6-C-β-D-吡喃葡萄糖基-5,7-二羟基香豆素。已经报道了其醋酸盐的 1 H NMR 光谱的一些有趣的特征,并对其 1 H 和 13 C NMR 光谱中的信号进行了分配。Dauroside D 是第一种天然香豆素 C-糖苷。
Biocatalytic C-Glucosylation of Coumarins Using an Engineered C-Glycosyltransferase
作者:Dawei Chen、Ridao Chen、Kebo Xie、Tian Yue、Xiaolin Zhang、Fei Ye、Jungui Dai
DOI:10.1021/acs.orglett.8b00378
日期:2018.3.16
The enzymatic synthesis of coumarin C-glucosides by an engineered C-glycosyltransferase, MiCGTb-GAGM, was explored in vitro and in vivo. MiCGTb-GAGM exhibited a robust C-glucosylation capability toward structurally diverse coumarin derivatives. The whole-cell bioconversion of MiCGTb-GAGM was exploited for large-scale production of coumarin C-glucosides. Two C-glucosides exhibited potent SGLT2 inhibitory activities with IC50 values at 10(-6) M. These findings provide cost-effective and practical synthetic strategies to generate structurally diverse and novel bioactive coumarin C-glycosides for drug discovery.
Coumarins ofHaplophyllum dauricum. 5,7-Dihydroxycoumarin and its C-glucoside