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We studied flavonoids from Allium cepa L. (onion, Liliaceae) and Raphanus sativus L. var. radicula Pers. (radish, Brassicaceae) in order to isolate biologically active phenolic compounds.Onion husks remaining after removing the seeds were ground and extracted eight times with CH 3 OH. The solvent was evaporated in vacuo. The solid was chromatographed over a silica-gel column with gradient elution by CHCl 3 :CH 3 OH (95:5-70:30).Elution of the column by CHCl 3 :CH 3 OH (90:10) gave 1.Compound 1, C 21 H 20 O 11 , mp 209-211°C. The UV spectrum (λ max 267.5, 297, 351 nm) was consistent with a flavonol derivative. UV spectra recorded with added ionizing and complexing reagents established that free phenolic hydroxyls were present at the 5-, 7-, and 4′-positions of the flavonol core [1]. The IR spectrum contained absorption bands for hydroxyls (3440-3290 cm -1 ), γ-pyrone carbonyl (1670 cm -1 ), aromatic double bonds (1618, 1521 cm -1 ), and glycoside C-O (1100-1000 cm -1 ).The PMR spectrum (100 MHz, C 5 D 5 N, δ, ppm, J/Hz) of 1 exhibited signals for aromatic protons of a 3,5,7,4′-tetrasubstituted flavone core at 6.50 (1H, d, J = 2.0, H-6), 6.55 (1H, d, J = 2.0, H-8), 8.32 (2H, d, J = 9.0, H-2′, H-6′), and 7.21 (2H, d, J = 9.0, H-3′, H-5′), an anomeric proton at 5.44 (1H, d, J = 7.0, H-1″), and other protons of the carbohydrate at 3.66-4.46 (6H, m). Acid hydrolysis of 1 gave kaempferol {2, C 15 H 10 O 6 , [M] + 286, mp 269-272°C, λ max 267, 325 (overlap.), and 368 nm} and D-glucose. A comparison of the UV spectra of 1 and kaempferol showed that the carbohydrate in the former was bonded to the C-3 hydroxyl [1]. Based on the results, 1 was identified as kaempferol-3-O-β-D-glucopyranoside (astragalin) [2]. Compound 1 was isolated from A. cepa for the first time. We investigated the alcohol extract of radish leaves by evaporating it and chromatographing the solid over a column of silica gel. Elution of the column by CHCl 3 :CH 3 OH (90:10) gave 3, C 27 H 30 O 14 , mp 185-186°C. UV spectrum (EtOH, λ max , nm): 266, 320, 347. The PMR spectrum (100 MHz, C 5 D 5 N, δ, ppm, J/Hz) of 3 exhibited signals for aglycon protons at 6.61 (1H, d, J = 2.0, H-6), 6.80 (1H, d, J = 2.0, H-8), 7.94 (2H, d, J = 9.0, H-2′, H-6′), and 7.15 (2H, d, J = 9.0, H-3′, H-5′), an L-rhamnose, two CH 3 groups at 1.30 (3H, d, J = 6.0, -CH 3 ) and 1.51 (3H, d, J = 5.5, -CH 3 ), two anomeric protons at 6.09 (1H, br.s, H-1″) and 6.11 (1H, br.s, H-1″′), and other carbohydrate protons at 3.92-4.62 (8H, m).The chromatographic mobility of 3 is similar to that of a glycoside. Acid hydrolysis of 3 produced kaempferol (2) and L-rhamnose.Therefore, 3 contains two L-rhamnose monomers. The UV spectra of 3 with added AlCl 3 and NaOCH 3 established that free phenolic hydroxyls were present at the 5-and 4′-positions [1].Based on the results and the literature, 3 was identified as kaempferol-3,7-di-O-α-L-rhamnopyranoside (lespedin) [3], which possesses hypotensor activity [4].Flavonoid 3 was isolated for the first time from R. sativus.

Herein we communicate results from a study of flavonoids from Sophora griffithii Stocks and Goebelia pachycarpa Schrenk.Leaves of S. griffithii act as an expectorant. The total flavonoids exhibit antibacterial activity. Apigenin, isoquercitrin, and quercetin glucoarabinoside have been isolated from the aerial part [1]. Flavonoids from the roots of this plant have not been previously studied.Ground air-dried roots of S. griffithii were collected near Tashkumir (Republic of Kyrgyzstan) and extracted at room temperature five times with ethanol (85%). The condensed extracts were diluted with water and worked up successively with CHCl 3 and ethylacetate. The CHCl 3 fraction was evaporated and chromatographed over a column of silica gel with gradient elution by CHCl 3 :hexane (95:5-50:50). Elution of the column with an 85:15 ratio of solvents gave 1.The isolated compounds were identified using UV, PMR, and mass spectra, chemical transformations, and direct comparison with authentic specimens.Inermin (1), C 16 H 12 O 5 , mp 180-181°C (benzene), [α] D -211° (c 0.4, ethanol). UV spectrum (EtOH, λ max , nm, log ε): 282 (3.53), 287 (3.59), 3.11 (3.78), characteristic of pterocarpanes [2]. The PMR spectrum (100 MHz, C 5 D 5 N, δ, ppm, J/Hz) exhibits signals at 3.42-3.92 (1H, m, H-6), 4.18 (1H, m, H-6a), 5.50 (1H, d, J = 6.0, H-11a), 5.85 (2H, d, J = 1.5, -OCH 2 O-), 6.60 (1H, s, H-10), 6.80 (2H, br.s, H-4, H-7), 6.86 (1H, dd, J = 8.5, 2.0, H-2), 7.50 (1H, d, J = 8.5, H-1). The mass spectrum of 1 exhibited a base peak for the molecular ion with m/z 284 and peaks for ions with m/z 147 and 175 due to ions a and b, respectively [2].Thus, 1 is 6a(R),11a(R)-3-hydroxy-8,9-methylenedioxypterocarpane (inermin) [2, 3]. Inermin was isolated from S. griffithii for the first time.The alkaloid pachycarpine was isolated from Goebelia pachycarpa. The aerial part of this plant is used in folk medicine for eczema, as an analgesic, and as a spasmolytic agent [4].Quercetin, kaempferol, and genistein and its xyloglucoside have been isolated previously from the aerial part of this plant [1].Chromatography over a silica-gel column using gradient elution by CHCl 3 :CH 3 OH isolated from the alcohol extract of roots of Goebelia pachycarpa flavonoid 2.Vexibinol (2), C 25 H 28 O 6 , mp 170-172°C, [α] D -36.5° (c 1.0, CH 3 OH). UV spectrum (EtOH, λ max , nm, log ε): 293 (4.23), 340 sh (3.69), characterisitc of flavanones [5]. The flavanone nature of 2 was confirmed by the PMR spectrum (100 MHz, DMSO-d 6 , δ, ppm, J/Hz), which exhibited signals at 5.52 (1H, dd, J = 13.0, 3.0, H-2), 2.56 (1H, q, J = 17.4, 3.0, H-3 ax ), and 3.12 (1H, q, J = 17.4, 13.0, H-3 eq ). The spectrum also contained signals for protons of a lavandulyl group, aromatic protons of a 5,7,8,2′,4′-substituted flavanone, and a 5-OH chelate. The mass spectrum of 2 contained peaks for ions (m/z) 424 [M] + , 406, 391, 301, 284, 283 (100%), 219, 165, 136, 124, etc.Thus, spectral data identified 2 as 5,7,2′,4′-tetrahydroxy-8-lavandulylflavanone or sophoroflavanone G (vexibinol) [6,7].Vexibino...