Flavonoids and Oleanolic Acid from Scabiosa caucasica

Abstract

In continuation of phytochemical investigations of plants of the Dipsacaceae family growing in the Republic of Azerbaidzhan [1, 2], we studied flowers of Scabiosa caucasica M.B. for flavonoid and triterpenoid content. Air-dried flowers (2 kg) collected during full flowering at the end of July 2006 near the village Slavyanka of Kedabek region of the Republic of Azerbaidzhan were extracted with ethanol (95%, 2×). The combined extracts were evaporated to 250 mL and left at room temperature. The resulting white precipitate was filtered off after a day.The filtrate was evaporated to 100 mL and diluted with water (300 mL). The resulting aqueous solution was treated successively with a mixture of ethylacetate and petroleum ether (1:1), ethylacetate, and n-butanol.Recrystallization of the aforementioned white precipitate from ethanol gave oleanolic acid, C 30 H 48 O 3 , mp 303-305°C, [α] D 20 -79 ± 2° (c 1.02, pyridine:methanol, 1:1) [2]. The extract obtained using ethylacetate:petroleum ether was evaporated and recrystallized from chloroform:ethanol to afford apigenin (1), C 15 H 10 O 5 , mp 343-345°C. IR spectrum (KBr, ν max , cm −1 ): 3300 (OH), 1655 (C=O), 1645, 1550 (C 6 H 5 ). UV spectrum (MeOH, λ max , nm): 270, 340 [3].1: R = R 1 = R 2 = R 3 = H 2: R = β-D-Glcp, R 1 = R 2 = H, R 3 = OH 3: R = β-D-Glcp, R 1 = R 3 = OH, R 2 = H 4: R = α-L-Arap(1→6)-β-D-Glcp, R 1 = H, R 2 = CH 3 , R 3 = OHThe ethylacetate extract was evaporated to dryness. The solid was dissolved in water (100 mL). The aqueous solution was shaken with ethylacetate (150 mL) and left for a day. The crystals that formed between the phases were separated and recrystallized from ethanol to afford cinaroside (2), C 21 H 20 O 11 ·2H 2 O, mp 270-272°C, [α] D 20 -48 ± 2° (c 0.5, formamide). UV spectrum (MeOH, λ max , nm): 256, 268, 350 (no change upon adding sodium acetate) [1]. The aqueous phase was evaporated to dryness. The solid was recrystallized from ethanol to afford quercimeritrin (3), C 21 H 20 O 12 , mp 245-247°C, [α] D 20 -52 ± 2° (c 0.5, methanol). IR spectrum (KBr, ν max , cm −1 ): 3480-3300,

Phytochemical and biological studies of Carduus pycnocephalus L.

“…Total acid hydrolysis, UV, 1 H NMR, 13 C NMR, HSQC, HMBC, COSY and FAB-MS were consistent with the literature data (Mabry et al, 1970;Garaev et al, 2008). Thus compound 6 was identified as diosmetin-7-O-a-L-arabinosyl-(1 000 -6 00 )-bDglucopyranoside or palustroside.…”

Triterpenoid saponins from Scabiosa stellata collected in North-eastern Algeria

“…The majority of Scabiosa, comprising about 100 species, occurs in the Mediterranean region (Carlson et al, 2012) and among them, approximately 12 species can be found in Algeria (Quezel and Santa, 1963). Up to date, chemical investigations of Scabiosa species have mainly revealed the presence of saponins (Alimbaeva et al, 1977, Baykal et al, 1998, Zheng et al, 2004, flavonoids, coumarins (Garaev et al, 2008), and iridoid glucosides (Papalexandrou et al, 2003, Polat et al, 2010. The aglycone of Scabiosa saponins were identified as oleanolic acid, hederagenin, and ursolic acid with glucose, rhamnose, xylose, and arabinose as sugar , Yusifova and Movsumov 2015, Zheng et al, 2004, or pomolic acid with glycoside containing an allose in Scabiosa rotata saponins (Baykal et al, 1997, Baykal et al, 1998.…”

Characterisation of phenolic antioxidants in Scabiosa arenaria flowers by LC–ESI-MS/MS and NMR

“…This compound was isolated at pure compound from S. tenuis Spruner ex Boiss, S. argentea L., S. atropurpurea L . S. caucasica M. B, S. ochroleuca L. and S. bipinnata C. Koch …”

“…[31] The glycosylated flavonoid, luteolin 7-O-glucoside, was identified for the first time in Scabiosa arenaria. This compound was isolated at pure compound from S. tenuis Spruner ex Boiss, S. argentea L., [28] S. atropurpurea L. [29] S. caucasica M. B, [32] S. ochroleuca L. and S. bipinnata C. Koch. [33] The third peak (compound 3) in the HPLC chromatogram ( Figure 3) was eluted at 20.5 min, exhibited a positive molecular ion at [MS+H] + at an m/z of 432.6 ( Figure 6a) and a positive fragment ion [MS 2 +H] + at an m/z of 270.7 (Figure 6b).…”