(4α,8α,12α,13S,14S)-16-(1-oxoethyl)-17,19-dinoratis-15-ene-4,13,14-tricarboxylic acid trimethyl ester 、 alkaline earth salt of/the/ methylsulfuric acid 生成 (4a
R)-4b
t.8
t-dimethyl-12-acetyl-(4a
rH.8a
cH)-dodecahydro-1
H-3
t.10a
t-etheno-phenanthrene-tricarboxylic acid-(1
t.2
t.8
c)-1.8-dimethyl ester