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As part of our ongoing investigation of the stenoendemic plants belonging to the Brassicaceae family, we report on the chemistry of Fibigia triquetra (DC.) Boiss. ex Prantl for the first time. Different plant parts (flower, leaf, stem, and seed) of F. triquetra were characterized and quantified for glucosinolates (GLs) according to the ISO 9167-1 EU official method based on the HPLC analysis of desulfo-GLs. A taxonomic screening showed that F. triquetra contained relatively high levels of C-4 GLs, namely but-3-enyl GL (gluconapin, 1a), 4-methylsulfanylbutyl GL (glucoerucin, 3a), and 4-methylsulfinylbutyl GL (glucoraphanin, 5a). GC-MS analysis of the volatile fractions obtained after enzyme hydrolysis and/or HPLC-ESI-MS of intact GLs confirmed the GL profile. Four minor GLs, namely isopropyl GL (glucoputranjivin, 6a), sec-butyl GL (glucocochlearin, 7a), pent-4-enyl GL (glucobrassicanapin, 2a), and 5-methylsulfanylpentyl GL (glucoberteroin, 4a) were also identified and quantified while 4-methylpentyl GL, 5-methylhexyl GL, and n-heptyl GL, were tentatively identified by GC-MS of their degradation products. Based on the major, as well as the minor GLs, this study shows differences in chemotaxonomy between F. triquetra and the related Degenia velebitica (Degen) Hayek as well as other investigated species of the genus Fibigia.

O-Glucosylation of 1-pentanol, 1-octanol, 2-phenylethanol, benzyl alcohol, (±)-2-pentanol and (±)-menthol in 1,4-dioxane, using anhydrous FeCl3, afforded anomeric mixture of the corresponding glucofuranosides as major and glucopyranosides as minor products in overall yields 20–52 %. Practical advantages of GC-MS for characterizing the prepared acetylated glucofuranosides are in the focus of this paper. Glucofuranoside tetraacetate spectra contain characteristic signals of glucone (acetylated glucose) along with fragments of the aglucone moiety. The mass range was 50–600 mass units and acetyl ion was not present in the spectra, which is of interest for differentiating glucofuranoside and glucopyranoside tetraacetates., O-glukozilacija 1-pentanola, 1-oktanola, 2-feniletanola, benzil-alkohola, (±)-2-pentanola i (±)-mentola u 1,4-dioksanu, rabeći bezvodni FeCl3, dala je odgovarajuće glukofuranozide kao glavne i glukopiranozide kao sporedne produkte s ukupnim prinosima 20–52 %. Praktične prednosti GC-MS za karakterizaciju pripravljenih glukofuranozida su u žari{tu ovoga rada. Spektri glukofuranozid tetraacetata sadrže karakteristične signale glukona (acetilirane glukoze) zajedno s fragmentima aglukonskoga dijela. Interval praćenja masa bio je 50–600 masenih jedinica i acetil-ion nije bio prisutan u spektrima, {to je od interesa za razlikovanje glukofuranozid i glukopiranozid tetraacetata.