6-OXYGENATED FLAYOSOIDS 'FROM LI-EUROLEA-\-,4 MA CROPHYLLA ATHASULUBELES Faculty of P h a r m a c y , C n i v e r s i i y of Istanbul, Istanbul, T u r k e y and Tolr J . MABRY
D e p a r t m e n t of Botany, T h e T n i ~ e r s i t yof T e s a s , Austin, T e x a s 78712
AkBSTR.iCT.-of twelve flavonoids isolated from -veurolaena macrophylla three, luteolin i-p-D-glucoside, 6-hydroxykaempferol 3,6,4'-trimethyl ether, and &hydroxykaempferol 6-methyl e t h e r 7-p-D-glucoside were found in this genus for t h e first time. T h e other known flavonoids were 6-hydrosyluteolin i-p-D-glucoside, quercetagetin 3,i-dimethyl ether, quercet aget in 3,6-dimethyl ether, quercet aget in &methyl ether 7-p-D-glucoside, quercetagetin i-8-D-glucoside, quercetagetin 3-methyl e t h e r 7-8-Dglucoside, 6-hydrosykaempferol i-t3-D-g1ucosidej kaempferol 3-8-D-glucoside, and kaempferol.
I n a continuation of our chemical investigation of the genus S e u r o l a e n a (Compositae-Heliantheae) (1-3), we report the isolation and characterization of twelve flavonoids from S.macrophylla Greenm. from Guatemala. We previously described fifteen flavonoids from S.oaxacana (1). seven from S.eenturana ( 2 ) , twelve from *\-. lobata (3) and six from -I-.macrocephala (3). The leaves of S.macrophylla were first extracted in a Soxhlet with benzene, chloroform and ethanol and, later, n-ith aqueous ethanol. Tu-o dimensional paper chromatography showed that most of the flavonoids were in the chloroform extract; the other extracts contained only traces of some of the same compounds. The chloroform extract yielded luteolin 7-P-D-glucoside (A), 6-hydroxyluteolin i-8-D-glucoside (j), quercetagetin 3.7-dimethyl ether (6), yuercetagetin 3,6dimethyl ether (i),quercetagetin 6-methyl ether 7-P-D-glucoside (8), 6-hydroxykaempferol 6-methyl ether 7-8-D-glucoside (9), quercetagetin 7-P-D-glucoside (lo), 6-hydroxykaempferol 7-p-D-glucoside (9), 6-hydroxykaempferol 3,6,4'trimethyl ether (11), quercetagetin 3-methyl ether i-P-D-glucoside (l), kaempferol 3-P-D-glucoside (1) and kaempferol.
EXPERIIIESTALi P L ~ SxirERI.iL.-Leaves T
of S.mcicrophjiia were collected in Guatemala, Quetzaltenango Department, upper reaches of t h e Pirineos, 5 k m below Santa Maria d e Jesus, at km post 197, Highxvay C.;i. 95 on January 20, 1980. 1-oucher specimens J . MacDougal K O 603 are deposited in t h e Herbaria of Duke University and t h e University of Texas a t Austin.
EXTRACTIOS ASD I D E TIFIC.ITIOS ~ OF FL i ~ o ~ o I .-General Ds chromatographic techniques were described in a previous paper (11. Ground leaves of LT. macrophylla (585 g) were extracted in a Soshlet with benzene, chloroform, ethanol, and aqueous ethanol. CHLOROFORM EXTRiCT.-The concentrate from t h e chloroform extract was chromatographed over a polyclar column (4x50 e m ) . Elution was initiated with Egger's solvent (methylene chloride-methanol-2 butanone-acetone, 20:10:5:1), and the polarity was gradually increased b y reduction of t h e amount of methylene chloride.
LUTEOLIS 7-p-D-GLUCOSIDE (2 mg), 6-HTDROXTLUTEOLIS 7-p-D-GLUCOSIDE (2 mg) .-rV d a t a taken both before and after hydrolysis, ms d a t a of underivatized compounds, both acid (0.1 S TFA) and enzyme hydrolysis, a s ne11 a s tlc comparison with standard samples established t h e structures. 'Spectra were recorded with t h e following instruments: uv Tarian Techtron model 635; p m r Varian 90 MHz and I-arian 200 M H z : m s DuPont 21-491. Adsorbants for cc and tlc were from E. hierck and hfacharey-?jagel.
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Journal of Katural Products
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[Vol. 45,
KO.
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~-HYDROXYKAEYPFEROL &METHYL
E T H E R 7-p-D-GLUCOSIDE (16 mg), &HYDROXYKAEMPFEROL (10 m g ) , KAEMPFEROL 3-p-D-GLUCOSIDE (20 mg) .-Each Of these compounds yielded the expected aglycones and sugars when hydrolyzed with both acid (0.1 T F A ) and enzyme. T h e pmr and uv spectral d a t a taken both before and after hydrolysis, ms of underivatized compounds, and standard sample comparisons showed t h e structures. 7-0-D-GLUCOSIDE
>-
QUERCETAGETIN &METHYL E T H E R 7-p-D-GLECOSlDE (18 m g ) , QUERCETAGETIN T-8-D-GLUCOGIDE (10 mg).-The colors under uv light (366 nm) indicated free 3-OH groups for both compounds. Hydrolysis with acid (0.1 N TFA4)and enzyme yielded quercetagetin 6-methyl e t h e r and quercetagetin as aglycones and glucose as sugar for both compounds. P m r and uv spectral d a t a before and after hydrolysis, rns of t h e underivatized compounds and direct comparison m-ith authentic samples established t h e identities of t h e tN-0 compounds.
QUERCET.\GETIS3-METHYL E T H E R i-p-D-GLL-COSIDE (9 mg) .-CV d a t a before and after hydrolysis, ms d a t a of underivatized compound as well as standard sample comparisons proved t h e structure. QUERCETAGETIS 3,7-DIMETHYL E T H E R (10 m g ) , QUERCET.\GETIS 3,&DI?rlETHTL E T H E R 6-HTDROXYK.IEhfPFEROL 3,6,4'-TKI>lETHYL E T H E R (15 mg) .\SD K.\E?rlPFEROL (5 mg) .-CV,
(15 mg), pmr and ms d a t a and standard sample comparison (except &hydroxykaempfero13, 6, 4I-trimethyl ether) proved t h e structures of the compounds.
ACKNOWLEDGNEST This work was supported a t t h e University of Texas a t Austin by the Robert A. Welch Foundation (Grant F-130) and t h e Kational Institutes of Health (Grant H D 04488) and at t h e University of Istanbul b y t h e Faculty of Pharmacy. We thank Mr. John hlacDouga1, Department of Botany, Duke Cniversity, for t h e collection of plant material.
Received 5 January 1981 1. 2. 3. 4. 5. 6.
7.
8. 9. 10.
11.
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