Euniciniatin

Euniciniatin [4(S),7(R)-epoxy-3(R)-hydroxy-1(R),11(S)-dolabella-8(Z),12(18)-dien-13-one; (1R,3R,4S,7R,11S)-3-hydroxy-12-isopropylidene-15-oxa-1,4,8-trimethyltricyclo[9.3.0.1^4,7]pentadec-8(Z)-en-13-one], C₂₀H₃₀O₃, was synthesized from a known dolabellane constituent of E. laciniata, namely, dolabellatrienone. The structure of this compound has a trans-bicyclo[9.3.0] tetradecane nucleus containing an additional 4,7-oxa bridge. The three O atoms in the molecule all belong to different functional groups, i.e. one is part of an ether bridge [O(3)-C(4) 1.452 (5) and O(3)-C(7) 1.429 (5) Å], one an alcohol [O(2)-C(3) 1.429 (6) Å] and one a ketone [O(1)-C(13) 1.233 (5) Å].

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