羧酸桃金娘烷醇酯的合成及抑菌活性研究

摘要

Myrtanol was prepared via hydroboration-oxidation reaction from β-pinene, then eight novel carboxylic myrtanyl esters (myrtanyl acetate (4a), myrtanyl propionate (4b), myrtanyl butyrate (4c), myrtanyl valerate (4d), myrtanyl cyclohexanecarboxylate(4e),myrtanyl benzoate(4f),myrtanyl p-methylbenzoate(4g) and myrtanyl p-methoxybenzoate(4h) were obtained through the reaction of myrtanol and carboxylic acids using N, N′-dicyclohexylcarbodiimide/dimethylaminopyridine ( DCC/DMAP) as catalyst. Structure characterizations were achieved by FT-IR,1 H NMR and ESI-MS. Antibacterial activity assays were carried out by agar dilution method. The results showed that compounds 4b,4c,4f,4g and 4h exhibited inhibitory activities (MIC was 256 mg/L) against the Gram positive bacterial Staphylococcus aureus,and compounds 4a,4b,4c and 4e exhibited inhibitory activities ( MICs were ranged from 128 to 256 mg/L) against the Gram negative bacterial Escherichia coli. more importantly. Compound 4a showed comparable activity ( MIC was 128 mg/L) to that of bromogeramine against E. coli. Comparing with the starting compound β-pinene and the intermediate myrtanol, this series of esters showed better antibacterial activities.%以β-蒎烯为原料,经硼氢化氧化反应合成了桃金娘烷醇,桃金娘烷醇与羧酸在N,N′-二环己基碳酰亚胺/4-二甲氨基吡啶( DCC/DMAP)的催化作用下反应,生成了8个羧酸桃金娘烷醇酯新化合物:乙酸桃金娘烷醇酯(4a)、丙酸桃金娘烷醇酯(4b)、正丁酸桃金娘烷醇酯(4c)、正戊酸桃金娘烷醇酯(4d)、环己烷羧酸桃金娘烷醇酯(4e)、苯甲酸桃金娘烷醇酯(4f)、对甲苯甲酸桃金娘烷醇酯(4g)、对甲氧基苯甲酸桃金娘烷醇酯(4h). 借助FT-IR、1 H NMR和ESI-MS对产物进行了结构表征,通过琼脂稀释法对所合成的化合物进行了抑菌活性测试. 结果表明,在该系列羧酸桃金娘烷醇酯中,化合物4b、4c、4f、4g和4h对革兰氏阳性菌金黄色葡萄球菌(Staphylococcus aureus)具有一定的抑菌活性,最小抑菌浓度(MIC)为256 mg/L,化合物4a、4b、4c和4e对革兰氏阴性菌大肠埃希氏菌(Escherichia coli)具有抑菌活性,MIC为128~256 mg/L. 其中,化合物4a对 E. coli的 MIC为128 mg/L与新洁尔灭相当. 相对于原料β-蒎烯和中间体桃金娘烷醇而言,该系列酯类化合物在抑菌活性上具有一定的提升.