R12 R H 母核名称RR1 R2 甾烷 HH 雌甾烷HCH3 HH 雄甾烷CH3CH3H 孕甾烷CH3CH3CH3CH2 胆烷CH3CH3CH3CH2CH2(CH3)CH 胆甾烷CH3CH3(CH3)2CHCH2CH2CH2(CH3)CH 有机化学第十九章萜类和甾体化 合物有机化学第十九章 萜类和甾体化 合物 10 R R1 R2 H 母核名称 R R1 R2 甾烷 H H H 雌甾烷 H CH3 H 雄甾烷 CH3 CH3 H 孕甾烷 CH3 CH3 CH3CH2 胆烷 CH3 CH3 CH3CH2CH2 (CH3 ) CH 胆甾烷 CH3 CH3 (CH3 )2CHCH2CH2CH2 (CH3 ) CH