title: Study of bis(bibenzyls) in bryophytes using electron ionization time-of-flight and electrospray ionization triple-quadrupole mass spectrometry.
abstract: A detailed analysis of mass spectra generated from bis(bibenzyl) compounds in bryophytes under electron ionization time-of-flight (EI-TOF) and electrospray ionization triple-quadrupole (ESI-TQ) mass spectrometry conditions is reported. Proposed structures of the fragment ions were obtained by tracking the functional groups of 15 bis(bibenzyls), the structures of which are similar except for some alkoxyl substituents and linkage sites of biphenyl ether bonds. The elucidation was aided by the use of accurate mass measurements. Attempts have been made to provide rational pathways for the formation of these fragment ions, and a generalized fragmentation mechanism is proposed. The bis(bibenzyls) mentioned in this study include three types according to their structure characteristics, i.e. one biphenyl ether bond (A-type), two biphenyl ether bonds (B-type), one biphenyl ether and one biphenyl bond (C-type). The three types display different EI-MS and ESI-MS/MS product profiles, by which the bis(bibenzyl) type and the number of alkoxyl substituents can be identified. Isomers of bis(bibenzyls) can be differentiated to some extent, while the linkage sites of biphenyl ether bonds are difficult to identify. The structure-fragmentation relationships will facilitate the characterization of other bis(bibenzyls) and this will be of value for the high-throughput screening of novel bis(bibenzyls) in bryophytes.
authors.affiliation: School of Pharmaceutical Sciences, Shandong University, 44 West Wenhua Road, Jinan 250012, P.R. China.
authors.forename: Huaifang
authors.initials: H
authors.lastname: Guo
authors.forename: Jie
authors.initials: J
authors.lastname: Xing
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Xie
authors.forename: Jianbo
authors.initials: J
authors.lastname: Qu
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Gao
authors.forename: Hongxiang
authors.initials: H
authors.lastname: Lou
mesh_terms: D001632:Bibenzyls / Q000737:chemistry*; D044002:Bryophyta / Q000737:chemistry*; D004988:Ethers, Cyclic / Q000737:chemistry*; D035926:Hepatophyta / Q000737:chemistry; D007536:Isomerism; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D001632:Bibenzyls; D004988:Ethers, Cyclic; D010936:Plant Extracts