CH3CH2CH2COOH,丁酸(CH3)2CHCOOH,2-甲基丙酸CH3CH2COOCH3,丙酸甲酯CH3COOCH2CH3,乙酸乙酯HCOOCH2CH2CH3,甲酸丙酯HCOOCH(CH3)2,甲酸异丙酯