Abstract
Odoroside H (Ia) was converted into 14β, 15β-epoxy-5β-card-20(22)-enolide-3β-ol-β-D-monodigitaloside (IIIa) in the following reaction sequence : Dehydration of odoroside H diacetate (Ib) with thionyl chloride in pyridine to give 14-anhydrodigitoxigenin-monodigitaloside diacetate (IIc). Mild hydrolysis of IIc with acid afforded the corresponding acetyl-free glycoside (IIa) together with monoacetate (IIb). These 14-anhydro compounds (IIa, IIb and IIc) were treated with N-bromoacetamide followed by alumina chromatography to yield 14β, 15β-epoxy-5β-card-20(22)-enolide-3β-ol-β-D-monodigitaloside (IIIa), and its mono- and diacetate (IIIb and IIIc) respectively. Microbiological deacetylation of IIIc furnished IIIa. In the same manner, digitoxin tetraacetate (VI) was changed into 14β, 15β-epoxy-5β-card-20(22)-enolide-3β-ol-β-D-tridigitoxoside (VIIIa).
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
