1972 年 92 巻 6 号 p. 768-771
Antibacterial tests against Hiochi bacteria (Bacillus saprogenes) of Japanese Sake were carried out on 36 kinds of methyl to octyl esters of 3-chloro-, 3-bromo- and 3-iodo-4-hydroxybenzoic acids. It was thereby found that the antibacterial activity increased with increasing number of carbon atoms in the alkyl chain composing the ester group, and introduction of one halogen also increased the original activity. For example, the activity of butyl 3-bromo-4-hydroxybenzoate was about 4 times that of butyl 4-hydroxybenzoate and ca. 8-16 times that of salicylic acid ; activity of butyl 3-iodo-4-hydroxybenzoate was ca. 8 times that of butyl 4-hydroxybenzoate and ca. 16-32 times that of salicylic acid. Effect of halogens in increasing the antibacterial activity increased approximately in the order of iodine, bromine and chlorine. In 6 kinds of 4-alkylresorcinol series, antibacterial activity also increased with increasing number of carbons in the alkyl chain, and the activity of 4-heptylresorcinol showed ca. 60 times that of salicylic acid and ca. 30 times that of butyl 4-hydroxybenzoate. Introduction of one formyl group into 4-alkylresorcinol resulted in doubling of the antibacterial activity, 5-heptyl-2, 4-dihydroxybenzaldehyde showing about 125 times the activity of salicylic acid and about 62 times that of butyl 4-hydroxybenzoate. Introduction of one chlorine also increased the antibacterial activity per test tube. In phenylaminothioformic acid esters also, increasing size of the alkyl group in the esters resulted in increasing antibacterial activity, butyl phenylaminothioformate showing about 30 times the activity of salicylic acid and about 15 times that of butyl 4-hydroxybenzoate.
