Loganin-type iridoids as chemotaxonomic markers in Glandularia gooddingii (Briq.) Solbrig

• Published in: Phytochemistry letters 2021-08, Vol.44, p.68-73
• Main Authors: Ahmed, Mai A.M., Mohamed, Nesma M., Woodman, Timothy J., Kociok-Köhn, Gabriele, Blagbrough, Ian S.
• Format: Article
• Language: English
• Subjects: 6β-Hydroxyipolamiide; Chemotaxonomic marker; Glandularia gooddingii (Briq.) Solbrig; Verbenaceae; X-ray crystallography
• ISSN: 1874-3900; 1876-7486
• DOI: 10.1016/j.phytol.2021.04.003

[Display omitted] •Glandularia (Verbenaceae) is a genus that has few published phytochemical studies.•Isolation of 3 loganin-type iridoids from Glandularia gooddingii (Briq.) Solbrig.•First report of 6β-hydroxyipolamiide X-ray crystal structure.•Chemotaxonomic importance of iridoid-type in closely related genera of Verbenaceae. Glandularia is one of the genera that has few published phytochemical studies and, for many years, it was considered to be within the genus Verbena. Verbena is known to be rich in iridoids, flavonoids, and phenylpropanoids. Three iridoid glucosides, 6β-hydroxyipolamiide, phlomiol, and pulchelloside I (3-5) were isolated from the methanolic extract of the whole plant of Glandularia gooddingii (Briq.) Solbrig and elucidated by extensive analysis of the 1D- and 2D-NMR as well as by HR-ESI-QTOF mass spectra. Identification of these iridoids and determining their chemical nature supports the chemotaxonomic classification of the genus Glandularia and defines certain members belonging to it. This is the first report of the X-ray crystal structure of 6β-hydroxyipolamiide (3).