Glycosides osladin

Ozonolysis of solasodine (1) and of the derived enone (8), with oxidative work-up, gave the keto-acids (18) and (19), respectively. These products were characterized as their methyl esters and as the acetates of the products of lithium aluminium hydride reduction of the methyl esters. Ozonolyses of (20) and (21) to give analogous products were also described. The aglycone (22) of the steroidal glycoside osladine has been synthesized from solasodine via the azomethine (23) and ketone (24). ... 

Osladin (62) is a steroidal glycoside that is about 500-times sweeter than sucrose. It was isolated by the Czech chemists Jizba and Herout in 1967 [112] from the rhizomes of European fern Polypodium vulgare known for its very sweet taste. Its structure has been recently revised [113] by total synthesis. During the synthesis it was shown that minute changes in the structure result in total loss of the sweet taste. Thus, this is a t5 ical glycoside whose overall structure - including the glycosidic part - is crucial for the respective activity. 

SYNTHETIC APPROACH TO INTENSELY SWEET GLYCOSIDES BAIYUNOSIDE OSLADIN... 

Another sweet-tasting saponin, osladin (17), occurs at rather low concentrations (about 0.03%) in the roots of the fern Polypodium vulgare (Hodge and Inglett, 1974). Similar steroidal glycosides have been isolated from the rhizomes of Polypodium glycyrrhiza (Kim et al., 1988 Kim and Kinghom, 1989). The major intensely sweet compound of that plant is polypodoside A, a 26-0-a-L-rhamnopyranosyl-pol-... 

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