(E)-2-(2-hydroxyethylidene)-6-methyl-5-heptenal (alpha-acariolal) and (E)-2-(hydroxyethyl)-6-methyl-2,5-heptadienal (beta-acariolal), two new types of isomeric monoterpenes from Caloglyphus polyphyllae (Acari: Acaridae)

• Published in: Bioscience, biotechnology, and biochemistry Vol. 67; no. 2; pp. 308 - 313
• Main Authors: Shimizu, N. (Kyoto Univ. (Japan)), Tarui, H, Mori, N, Nishida, R, Kuwahara, Y
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Society for Bioscience Biotechnology and Agrochemistry 01.02.2003
• Subjects: ACARIDAE; Acaridae - chemistry; Aldehydes - chemistry; ANIMAL GLANDS; Animals; Biological and medical sciences; BIOSYNTHESIS; CHEMICAL STRUCTURE; FRACTIONATION; Fundamental and applied biological sciences. Psychology; Gas Chromatography-Mass Spectrometry; Isomerism; LACTONES; Lactones - chemistry; MONOTERPENES; Monoterpenes - chemistry; Monoterpenes - isolation & purification; NMR SPECTROSCOPY; Nuclear Magnetic Resonance, Biomolecular; SECRETION; Acaridae; α-acariolal; Caloglyphus polyphyllae; monoterpene; β-acariolal
• ISSN: 0916-8451; 1347-6947
• DOI: 10.1271/bbb.67.308

The opisthonotal gland secretion of the acarid mite, Caloglyphus polyphyllae, contained two new monoterpenes, (E)-2-(2-hydroxyethylidene)-6-methyl-5-heptenal (1) and (E)-2-(2-hydroxyethyl)-6-methyl-2,5-heptadienal (2), to which we have given the trivial names alpha- and beta-acariolal in relation to alpha- and beta-acaridial (3 and 4), respectively. Elucidation of the structure of 1 was established mainly from 1H-NMR and GC/MS spectral data after partial purification, together with the fact that 1 was recovered in the more-polar fraction from a silica gel column than alpha- and beta-acaridial (3 and 4) present in the secretion. Compound 2 was obtained in the same fraction as a mixture with 1. Based on the facts that 2 had the same molecular weight by GC/MS and the same polarity as that of 1, compound 2 was assumed to be a structural analog of 1. The structures of compounds 1 and 2 were confirmed by their synthesis in nine and ten respective steps starting from alpha-bromo-gamma-butyrolactone.