Structural Elucidation of Twelve Novel Esters Composed of Five Fatty Acids and Three New Branched Alcohols Together with Four Monoterpenoids from Sancassania shanghaiensis (Acari: Acaridae)
作者:Tomoyo SAKATA、Kimiko OKABE、Yasumasa KUWAHARA
DOI:10.1271/bbb.65.919
日期:2001.1
A total of 12 novel esters and four monoterpenoids (rosefuran, (2R,3R)-epoxyneral, and α- and β-acaridials) were detected by GC/MS analyses as the opisthonotal gland components of Sancassania shanghaiensis. The acidic fraction after hydrolysis was composed of five common fatty acids (palmitic, stearic, oleic, linoleic and arachidic acid), while the alcoholic fraction consisted of two major components (C6 and C8 alcohols with branched methyls), together with a trace amount of C9 alcohol. The Two major alcohols were identified as new alcohols [(S)-2-methylpentanol and (2S,4S)-2,4-dimethylhexanol] by comparing the physico-chemical data of their 3,5-dinitrobenzoates with those of regio-selectively synthesized alcohols. The C9 alcohol was suggested as (2S,4S)-2,4-dimethylheptanol, based on a structural and biogenetic analogy to the C6 and C8 alcohols. Five of the compounds were each identified by GC to be (S)-2-methylpentyl esters from five fatty acids, and the other five components likewise as (2S,4S)-2,4-dimethylhexyl esters. The remaining two were suggested as (2S,4S)-2,4-dimethylheptyl Stearate and linolate.
GC/MS分析在Sancassania shanghaiensis的抱粉腺成分中检测到总共12种新型酯和4种单萜(玫瑰呋喃、(2R,3R)-环氧橙花醇以及α-和β-刺檗二醇)。经过水解后的酸性部分由5种常见脂肪酸(棕榈酸、硬脂酸、油酸、亚油酸和花生酸)组成,而醇性部分则主要由两种成分(带有支链甲基的C6和C8醇)组成,同时含有微量的C9醇。通过比较其3,5-二硝基苯甲酸酯的物理化学数据与选择性合成醇的数据,确认这两种主要醇为新型醇[(S)-2-甲基戊醇和(2S,4S)-2,4-二甲基己醇]。根据结构和生物学上的相似性,C9醇被推测为(2S,4S)-2,4-二甲基庚醇。通过GC鉴定,五种化合物分别为五种脂肪酸的(S)-2-甲基戊酯,另外五种成分同样为(2S,4S)-2,4-二甲基己酯。剩下的两种被推测为(2S,4S)-2,4-二甲基庚酯的硬脂酸酯和亚油酸酯。