脂肪酸の陽極合成 (第5報)

3,3-Dimethylvaleric Acidのエステル類の合成

抄録

3, 3-Dimethylvaleric acid, homologous to (+)-3-methylvaleric acid, which is considered to be one of the aromatic components of tobacco leaf, and 12 of its esters were prepared. Some of lower esters of this series were found to have an aroma and the odor tended to weaken in higher esters. The boiling point and refractive index of these esters became higher with increasing molecular weight but esters with branched-chain alkyl group did not follow this rule. These compounds and the 3, 3-dimethylated, branched fatty acids (C₇H₁₄O₂ to C₂₃H₄₆O₂) reported previously were tested in Dubos medium for growth-inhibitory action against human-type tubercle bacilli, H₃₇RV strain. Higher fatty acids above C₁₇H₃₄O₂ (3, 3-dimethyl-pentadecanoic acid) showed such activity in 320, 000 dilution and approximately the same result was obtained with bovine-type tubercle bacilli, B₁₅ strain. In Kirchner medium, none of the compounds showed any antibacterial activity. Derivatives of 3, 3, 6, 6-tetramethylsuberic acid and 3, 3-dimethylisooctanoic acid were prepared.