CH CH3 CHCh2 Ch2c--oh 4-甲基戊酸 4-Methylpentanoic acid CH2CH3 CH3 O Ho-CCHoCHCHoCHoCHCHoC-OH 3-甲基-6-乙基辛二酸 3-Ethyl-6-methyloctanedioic acidOrganic Chemistry Organic Chemistry Xiamen Xiamen University University CH 3CHCH 2CH 2 C O OH CH 3 4-甲基戊酸 4-Methylpentanoic acid CC H 2CHCH 2CH 2CH C H 2 C O OH O CH 3 HO CH 2CH 3 3-甲基-6-乙基辛二酸 3-Ethyl-6-methyloctanedioic acid