Polypodoside structure

Three steroidal saponins, polypodosides, were isolated from the rhizomes of Polypodium glycyrrbiza DC. Eaton (Polypodiaceae).37,38 According to the corrected structure of osladin, the structure of polypodoside was also revised.39 Polypodoside A was shown to be highly sweet (600 times sweeter than sucrose). 

Steroidal Saponins The fern genus, Polypodium, has so far yielded three sweet steroidal saponins, namely, osladin (45) and polypodosides A and B (46, 47). The first-named of these compounds was structurally determined without full stereochemistry as an isolate of P. 

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