Flavonoids of Bupleurum plantagineum

Abstract

Bupleurum (Apiaceae) species are used in traditional medicine to treat various diseases. Bupleuri Radix (roots of Bupleurum) is one of the most frequently prescribed crude herbs in the prescriptions of traditional Chinese medicine for the treatment of inflammatory and autoimmune diseases [1]. It is used in at least 66% of the formulations/prescriptions in traditional Chinese medicine [2]. Bupleurum species have been reported to possess anti-inflammatory [3], antioxidant, and hepatoprotective effects [4][5][6][7][8]. Saikosaponins are the principal secondary metabolite of Bupleurum [2,[4][5][6][7][8] in addition to polyacetylenes, terpenoids, and two flavonoids (tamarixetin 3-robinobioside and tamarixetin 3-galactoside) [9] and polysaccharides [10].Bupleurum plantagineum (Apiaceae), an endemic species [11], was collected around Cap Carbon at Bejaia (Eastern Algerian) in may 2004 and authenticated by Prof. Gerard De Belair (Annaba, Algeria). A voucher specimen was deposited in the Herbarium of the Laboratory of Therapeutic Substances (LOST) at Mentouri University (LOST/Bp/05/04).Air-dried and powdered aerial parts (1 kg) of Bupleurum plantagineum were macerated in a methanolic solution (70%). The extract was successively concentrated to dryness (under low pressure); the residue was dissolved in boiling water and extracted with petroleum ether, dichloromethane, ethyl acetate, and n-butanol, successively.The butanolic extract was column chromatographed on polyamid SC6, eluting with toluene-methanol with increasing polarity. Whatman 3MM paper chromatography using 15% AcOH and BAW [n-BuOH-AcOH-H 2 O, 4:1:5 (upper phase)] and TLC on polyamid DC6, eluting with H 2 O-MeOH-methylethylketone-acetylacetone (13:3:3:1), followed by a column flash chromatography over Sephadex LH-20 in MeOH, led to three pure flavonoids 1-3, which were identified using UV, 1 H NMR, 13 C NMR, and MS analysis [12][13][14].Acid Hydrolysis. The pure compounds were treated with 2 M HCl at 100qC for 1 h. The hydrolysates were extracted with EtOAc, and the aglycones were identified by their UV spectra in methanol and by comparison of their R f with authentic samples.Sugars were identified in the aqueous residue by comparison with authentic samples on silica gel TLC impregnated with 0.2 M NaH 2 PO 4 , solvent Me 2 CO-H 2 O (9:1), and revealed with aniline malonate.Compound 1, C 15 H 10 O 7 , yellow needles (acetone), mp >300qC. This compound was characterized as quercetin [12][13][14].Compound 2, C 27 H 30 O 16 , mp 250-254°C. UV (MeOH, O max , nm): 257, 300 sh, 356; +NaOH: 272, 325, 407; + AlCl 3 : 275, 290, 350 sh; +HCl: 268, 285 sh, 350, 390; +NaOAc: 271, 385; +H 3 BO 3 : 263, 378. FAB + -MS, m/z 611 [M + H] + . 1 H NMR (250 MHz, CD 3 OD, G, ppm, J/Hz): 7.80 (1H, d, J = 2.0, H-2c), 7.75 (1H, dd, J = 9.0, J = 2.0, H-6c), 6.85 (1H, d, J = 9.0, H-5c), 6.30 (1H, d, J = 2.0, H-8), 6.20 (1H, d, J = 2.0, H-6), 5.12 (1H, d, J = 7.0, H-1cc glucose), 4.55 (1H, d, H-1cccrhamnose), 3.20-3.90 (10H, protons of rutinose), 1.1 (3H, d, J = 6.2, H-6cccrhamnose). Acid ...

6"'- O -acetylisospinosin, a new C -glycosylflavone and known compounds from the aerial parts of Cladanthus mixtus

“…The phytochemical investigation from the n-butanol extract from the aerial parts of C. mixtus Magid et al 2017), 14 flavonoids namely, apigenin (5) (Nacer et al 2006), kaempferol (6) (Gangwal et al 2010), luteolin (7) (Ode and Asuzu, 2014), luteolin 3'-O-methylether (chrysoeriol) (8) (Laggoune et al 2008), luteolin 4'-O-β-D-glucopyranoside (9) (Krenn et al 2003), luteolin 3'-O-β-D-glucopyranoside (10) (Jiang et al 2010), quercetin 3-O-β-D-glucopyranoside (isoquercitrin) (11) (Touafek et al 2011), quercetin 3-O-β-D-rutinoside (12) (Bencheraiet et al 2011), quercetin 3-O-methylether (isorhamnetin) (13) ( Krenn et al 2003), 6-hydroxyquercitrin-3-O-β-D-glucopyranoside (14), patulitrin (quercetagetin-6-methylether-7-O-β-D-glucopyranoside) (15) (Shahzadi and Shah, 2015), 6-hydroxykaempferol-7-O-β-Dglucopyranoside ( 16) (Valant-Vetschera et al 2003), (2R,3R)-taxifolin 3-O-β-Dgalactopyranoside ( 17), (2S,3S) taxifolin 3-O-β-D-glucopyranoside (isoglucodistylin) (18) (Sakushima et al 2002), 5 phenolic acids namely trans-caffeic acid (19) (Bhatt, 2011), transferulic acid (20) (Liao et al 2014), trans-p-coumaric acid (21) (Liao et al 2014), 4hydroxybenzoic acid (p-hydroxybenzoic acid) ( 22) (Dhakal et al, 2008), protocatechuic acid (23) (Liao et al 2014), one phenol glycoside, 2-hydroxy-5-(2-hydroxyethyl)phenyl-β-Dglucopyranoside (24) (Lu and Foo, 1999), a monoterpene glycoside, chamolol (25) (Zaiter et al 2007), and 6 quinic acids (3-O-caffeoylquinic acid methylester (neochlorogenic acid methyl ester) (26) (Kozawa et al 1983), 5-O-caffeoylquinic acid ( 27) (Liu et al 2013), 1,5-di-Ocaffeoylquinic acid (28) (Islam et al 2002), 3,5-di-O-caffeoylquinic acid (29) (Liu et al 2013), 3,5-di-O-caffeoylquinic acid methyl ester (30) (Liu et al 2013), and 4,5-di-O-caffeoylquinic acid (31) (Liu et al 2013).…”

The Chemistry and Biological Activities of Natural Products from Northern African Plant Families: From Taccaceae to Zygophyllaceae

“…Additionally, Selim and Ouf recently isolated the coumarins 6-hydroxy-7-methoxy-4-methyl coumarin ( 159 ), 6-hydroxy-7-methoxy coumarin ( 160 ) and xanthotoxin ( 161 ), together with β-sitosterol ( 73 ) from the aerial parts of the plant [ 129 ]. Meanwhile, Bencheraiet et al isolated the flovonoids; quercetin ( 162 ) rhamnetin ( 163 ), isorhamnetin ( 164 ), rhamnazin ( 165 ), three 3- O -glucosides respectively linked to; rhamnetin ( 166 ), isorhamnetin ( 167 ) and rhamnazin ( 168 ); one 7- O -glucoside of isorhamnetin ( 169 ), two diglycosides; 3- O -rutin of quercetin ( 170 ) and isorhamnetin ( 171 ), together with quercetin 7,3,3′- O -triglucoside ( 172 ) from the sister species, A. visnaga , collected from Algeria (used in Algerian folk medicine to treat vitiligo) [ 130 ]. The biological tests showed that compounds 159 and 160 are good anti-inflammatory agents, both compounds exhibiting appreciable inhibition of edema, particularly compound 159 , which exhibited an 87 % edema inhibition of 37.81 %, comparable with that of the standard drug indomethacin (60.50 % at 0.01 mg/100 g dose), while compound 161 exhibited mild anti-inflammatory activity [ 129 ].…”

Development of a sensitive ultra high performance liquid chromatography with tandem mass spectrometry method for the simultaneous quantification of nine active compounds in rat plasma and its application to a pharmacokinetic study after administration of

“…, and homoeriodictyol (Hedt-IV) [18][19][20]. Rham-III is a new flavonoid glycoside that was isolated from the branches and leaves of V. coloratum by us [21].…”

“…Our previous report used the scavenging activity of the stable 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical to assess the potential antioxidant activity. These active flavonoids include homoeriodictyol‐7‐ O ‐β‐ d ‐apiose(1→5)‐β‐ d ‐apiose(1→2)‐β‐ d ‐glycoside (Hedt‐I), homoeriodictyol‐7‐ O ‐β‐ d ‐apiose(1→2)‐β‐ d ‐glycoside (Hedt‐II), isornetin‐3‐ O ‐β‐ d ‐glucoside (Isor), homoeriodictyol‐7‐ O ‐β‐ d ‐glycolside (Hedt‐III), rhamnazin‐3 ‐Ο ‐β‐ d ‐glucoside (Rham‐I), rhamnazin‐3‐ Ο ‐β‐ d ‐ (6″‐β‐hydroxy‐β‐methyglutaryl)glucoside (Rham‐II), rhamnazin‐3‐ Ο ‐β‐ d ‐ (6″‐β‐hydroxy‐β‐methyglutaryl)‐β‐ d ‐glucoside‐4′ ‐Ο ‐β‐ d ‐glucoside (Rham‐III), 5‐hydroxy‐3,7,3′‐trimethoxyflavone‐4′‐ O ‐β‐ d ‐glucoside (Httf), and homoeriodictyol (Hedt‐IV) . Rham‐III is a new flavonoid glycoside that was isolated from the branches and leaves of V. coloratum by us .…”