Chiloscyphus polyanthos

Chiloschyphone (1) is a sesquiterpene ketone isolated from Chiloscyphus polyanthos and its absolute configuration has not been determined (3). The structure of this compound was first reported in 1972 (4), but later a total synthesis of this compound revealed that this original structure was wrong (5). Quite recently the correct structure was proposed by Connolly and his co-workers to be that depicted as in 1 (3). The synthesis of this correct structure has not been achieved yet. We plan to introduce cw-dimethyl groups by 1,4-addition, followed by an intramolecular aldol cyclization to yield a hydrindane skeleton (Scheme 1). The optical resolution must be possible at the stage of compound 4. 

Two e -eudesmanolides, ewr-3-oxodiplophyllin (358) and e -5-(3-hydroxydiplophyllolide (362), occur in European Chiloscyphus polyanthos, together with the previously known ewr-diplophyllin (355) and ent-diplophyllolide (356) (72). The structures of the lactones (358) and (362) were based on spectroscopic correlation with the co-metabolites (355,356). The stereochemistry of (362), including the center containing the tertiary hydroxyl group, was based on its positive Cotton effect and on biogenetic considerations. ( )-3-Oxodiplophyllin (358) has been reported as an intermediate in the synthesis of yomongin (399), the 1,2-dehydroderivative of (358), before its isolation from a liverwort (Scheme 48) 100). 

Chiloscyphus polyanthos Cholesterol Brassicasterol Stigmasterol Sitosterol... 

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