Characterization and identification of chemical compositions in the extract of Artemisia rupestris L. by liquid chromatography coupled to quadrupole time‐of‐flight tandem mass spectrometry

Abstract

Liquid chromatography coupled to negative electrospray ionization (ESI) tandem mass spectrometry (MS/MS) employing a time-of-flight tandem mass spectrometer was used in the structural determination of phenolic compounds and sesquiterpenoids occurring in the extract from Artemisia rupestris L. A total of 91 compounds including chlorogenic acid derivatives, flavonoids (aglycone, O-glycosyl, C-glycosyl and C,O-glycosyl), 2-phenoxychromones and guaiane sesquiterpenoids were identified by comparing the retention time and fragmentation behavior with reference standards or according to accurate mass measurement and the characteristic fragmentation at low and high collision energy. Most of these compounds were reported in Artemisia rupestris L. for the first time. Meanwhile, the proposed pathway and the major diagnostic fragmentation of 2-phenoxychromone and rupestonic acid were investigated to trace 2-phenoxychromone and rupestonic acid derivatives in crude plant extracts. According to these rules, we have successfully characterized five potential novel compounds including three 2-phenoxychromones (6-demethoxy-4'-O-methylcapillarisin-O-hexosylglucuronide, 6-demethoxy-4'-O-methylcapillarisin-O-pentosylhexoside and 6-demethoxy-4'-O-methylcapillarisin-O-deoxyhexosylhexoside) and two sesquiterpenoids (hexosyl-glycurinide-rupestonic acid and hexoside-rupestonic acid).

Extraction optimisation using water/glycerol for the efficient recovery of polyphenolic antioxidants from two Artemisia species

“…These compounds are likely to correspond to 5-O-caffeoylquinic acid (neochlorogenic acid), 3,5-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid, as reported for A. argentea L' Hér [28]. These particular substances have also been shown to be major constituents in A. selengnesis Turcz [32], A. rupestris [46] and A. annua [47,48], while in A. vulgaris the major derivatives identified were 3,5-di-O-caffeoylquinic acid and 1,5-di-O-caffeoylquinic acid [49]. Regarding the flavonoid fraction, peaks 3, 4 and 5 were identified as apigenin glycosides and are likely to correspond to apigenin-6,8-di-C-glucoside (vicenin-2), apigenin-6-C-arabino-8-C-glucoside (isoschaftoside) and apigenin-6-C-gluco-8-C-arabinoside (schaftoside), as shown for A. annua and A. arborescens [48,50].…”

Rupestonic acids B–G, NO inhibitory sesquiterpenoids from Artemisia rupestris

“…The potent anti-inflammatory properties of sesquiterpenes have received considerable attention. 29 Guaianes, such as pechueloic acid (8), are D 11,13 -didehydro derivatives. This makes them to be good Michael accepters and hence biologically active.…”

“…[9][10][11][12] The structural novelties and significant bioactivities of the isolates prompted us to search for more active sesquiterpenoids from other Artemisia species, a chemical investigation on the whole plants of A. rupestris 13 was thus carried out as part of our ongoing works on Artemisia species. Finally, six new guaiane sesquiterpenes, rupestonic acids B-G (1-6) were isolated together with six known compounds (7)(8)(9)(10)(11)(12) (Fig. 1): 14 ilicic acid (7), 15 pechueloic acid (8), 16 5b-hydroxy-4-oxo-11(13)-dehydroiphionan-12-oic acid (9), 17 1b,4b-dihydroxy-3b-acetoxygermacra-5E,10(14)-diene (10), 18 1,5-epoxy-4-hydroxyguai-11(13)-en-12-oic acid (11), 19 and loliolide (12).…”

“…Finally, six new guaiane sesquiterpenes, rupestonic acids B-G (1-6) were isolated together with six known compounds (7)(8)(9)(10)(11)(12) (Fig. 1): 14 ilicic acid (7), 15 pechueloic acid (8), 16 5b-hydroxy-4-oxo-11(13)-dehydroiphionan-12-oic acid (9), 17 1b,4b-dihydroxy-3b-acetoxygermacra-5E,10(14)-diene (10), 18 1,5-epoxy-4-hydroxyguai-11(13)-en-12-oic acid (11), 19 and loliolide (12). 20 The structures of the isolates were identified on the basis of extensive spectroscopic analysis, and their absolute configurations were established by quantum chemical calculations of their electronic circular dichroism (ECD) spectra based on the NOESY correlations.…”

“…[2][3][4] Recently a series of guaipyridine sesquiterpene alkaloids have been also isolated from the flowers of this plant. [5][6][7][8] In our previous research, a series of sesquiterpenes were isolated from Artemisia species and exhibited remarkable cytotoxicities and anti-inflammatory activities. [9][10][11][12] The structural novelties and significant bioactivities of the isolates prompted us to search for more active sesquiterpenoids from other Artemisia species, a chemical investigation on the whole plants of A. rupestris 13 was thus carried out as part of our ongoing works on Artemisia species.…”