Diazomethane ring expansion of 12-acetoxy-C2-bismethanotwistan-8-one (11) followed by the Wolff–Kishner reduction and the Jones oxidation gave C2-methanoditwistan-4-one (14) whose incubation with Rhodotorula rubra afforded the (−)-enantiomer 16, which was converted into (−)-(1S,3S,6S,7S,10S,12S)-D3,-tritwistane (7).
12-乙酰氧基-C2-bismethanotwistan-8-one (11) 的
重氮甲烷扩环,然后是 Wolff-Kishner 还原和琼斯氧化得到 C2-methanoditwistan-one (14),其与红酵母一起孵育得到 (-) -对映异构体 16,其转化为 (-)-(1S,3S,6S,7S,10S,12S)-D3,-tritwistane (7)。