Chaudhuri, Prabir K

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IndianJournalof ChemistryVol. 37B, January1998, pp. 98 - 99Nonalkaloidal constituents of the seeds ofGloriosa superba'PrabirK ChaudhuriPhytochemicalTechnologyDivisionCentralInstituteof MedicinalandAromaticPlantsPO CIMAP,Lucknow226 015, IndiaReceived14 Febery1996; accepted(revised)7 February1997From the seeds of Gloriosa superba L. (Liliaceae),two new compounds ursolic acid- 3~-tetracosanoate 1and 6-hydroxy-24-oxotritriacontane 2, and the knowncompounds hentriacontane, nonacosane, palmitic acid,~-sitosterol, ~-sitosterol-3~-D-glucoside, ~-sitosterol-3~-D-palmitate and stearate, I-n-butyl-~-D-fructopyranoside, luteolin, orcinol and 2-hydorxy-6-methoxybenzoic acid have been isolated andcharacterized by their spectral and chemical studies.Gloriosa superba is used in the Ayurvedic systemof medicine for a variety of medicinal purposes',Though there are reports of thirty alkaloids fromthe tuber, bulb, com, seeds and flowers ofGisuperba': 3, no work has been reported on thenonalkaloidal constituents of its seeds. Incontinuation of our work on phytochemicalinvestigation of medicinal plants', the presentinvestigation was carried out on the seeds of thisplant leading to the isolation and characterizationof known lipids, sterols, terpenoids, phenolics andtwo new compounds ursolic acid-3[3-0-tetracosanoate 1 and 6-hydroxy-2-oxotritriacontane 2. This is the first report of theisolation of nonalkaloidal compounds from theseeds of G. superba.Compound 1, isolated as an amorphous solid(m.p. 164°) from the hexane-EtOAc fraction,showed its M+ peak at rnJz 806 in its FAB-MS but,no M+ ion in its EI-MS. Its IR spectrum indicatedthe presence of ester (1742 cm', acid 1708 cm')and double bond (1639 cm') functions and a longchain moiety (720 cm'). It was found to behomogeneous on TLC and gave positive LB testtCIMAPPublicationNo. 94-14J.Note30no14 13o1\1- R,=H; R= CH3-(CH2)2iC-1Q' R;=R = H1b CH3- (C H2>22-COOHte R,= ••.•c ; R= Hm/z 115 f.,m/z 101 ,.~"'lm/z367HO: ~I I16 I I 14 II I 0 II I.. Il -~m/ z 393....•m/z 423MeMe2for triterpenoid. Its EI-MS exhibited significantpeaks at rnJz 248, 203 and 133 indicating thepresence of a ~'2-amyrin skeleton with a carboxylgroup at C-17 position and no OH group on ringD1E4. Alkaline hydrolysis of 1 gave an alcohol la(M+ 456) and a long chain acid Ib (M+ 368).Compound la gave positive L-B test and onmethylation with diazomethane it furnished amonomethyl ester Ic (M+ 470). Hence, compound1 is a long chain ester of a triterpenoid alcoholhaving a carboxylic group at C-17. The IH NMR of1 (80 MHz. CDCI3) showed a doublet at 0 2.21 (H-18, J=12.2 Hz) indicating the presence of ~12_ursane skeleton5•6• It also showed the presence ofeight methyl groups (0 0.65-1.10, m), an equatorialC-3 acyloxy group (04.51 dd, J=3, 7 Hz) and anolefinic proton (0 5.25, m). The methylene protonsappeared in the region 0 1.25 - 1.45 and the signalat 0 2.30 (2H, m) was assigned to oxomethylenegroup of the ester side chain. Compound Ic wasfound to be ursolic acid methyl ester by its spectraldata and comparison with an authentic sample.Compound Ib (M+ 368) was found to betetracosanoic acid from its spectral data (IR, 'HNMR and MS). Hence, compound I was identifiedas ursolic acid -3J3-0-tetracosanoate and this is thefirst report of its natural occurence.Compound 2 was isolated from EtOAc-hexane(l: 19) eluates as an amorphous solid, m.p. 72° (M+at rnJz494). Its IR spectrum showed bands at 3425,1722, 730 and 725 em" due to OH, CO functionsand a long chain moiety. The 'H NMR spectrum of2 (80 MHz, CDCI3) showed a carbinyl methineproton at 0 3.64 (lH, m, WIIZ= 14 Hz) and theoxomethylene protons at 2.25 (4H, m). It showedmethine and methylene protons at 0 1.62 and 1.27whereas methyl signals appeared at 0 0.90 (6H,br.t). In its EI-MS, the ion peaks at rnJz 101(1.3%),83(25%) and 393(1.2%) showed the presence ofOH at C-6 and the peak at rnJz 364 (16%) due toMclafferty rearrangement involving the carbonylgroup was indicative of an oxo group at C-24position'. Thus, compound 2 was identified as 6-hydroxy-24-oxotritriacontane. Other compoundsisolated were identified as the knownhentriacontane, nonacosane, palmitic acid, stearicacid, ~-sitosterol-3~-D-palmitate and stearate, J3-sitosterol, ~-sitosterol -3~-D-glucoside, I-n-butyl-J3-D-fructopyranoside, luteolin, orcinol and 2-hydroxy-6-methoxybenzoic acid from thecomparison of their spectral (JR, 'H NMR and MS)and physical data with those reported in literature"10. Isolation of hentriacontane, nonacosane, palmiicacid, J3-sitosterol-3J3-D-palmitateand stearate, I-n-butyl-l J3-D-fructopyranoside, orcinol and 2-hydroxy-6-methoxybenzoic acid constitutes theirfirst isolation from Gisuperba',Experimental SectionGeneral. Melting points are uncorrected. IRspectra were recorded on a Perkin-Elmer 1710 FTspectrophotometer, mass spectra on a Jeol D-300spectrometer and 'H NMR specta on a Varian FT80A machine using CDCl3 and DMSO-d6 assolvents and TMS as internal standard. Columnchromatography and TLC were carried out onsilica gel (E. Merk, India) and the spots wereNOTES 99exposed to Iz vapour or to 50% HZS04 at 1200 for 5min. for detection.The seeds of G. Superba were collected fromNew Delhi market as a commercial material andidentified by our Botany Division where a voucherspecimen has been deposited.Extraction and isolation. Extraction of theseeds of G. Superba L. (1 kg) has been describedearlier'. Defatted hexane concentrate and acidinsoluble material were chromatographedseparately on silica gel (60-120 mesh) and 150fractions of 250 mL each were collected usingsolvent and solvent mixtures of increasing polarityas eluants. Similar fractions were mixed togetheraccording to their TLC behaviour.Ursolic acid-Sjl-tetracesanaete 1. EtOAc-hexane fractions on column chromatography andpreparative TLC on Si gel (CHCI3-MeOH; 99: 1)afforded the compound I (0.025 g), n, 0.40(CHCI3-MeOH; 49: 1).Hydrolysis of 1. Compound 1 (10 mg) wasrefluxed with 5% KOH in MeOH for 2 hr and aftercooling, the hydrolysate was acidified with 2NHCI, and extracted with CHCl3 to affordcompounds 1a and 1b after prep-TLC.Compound Ic was prepared from 1b by usualdiazomethane treatment.6-Hydroxy-24-oxotritriacontane 2. CHCI3-hexane (1: 1) fractions on chromatography andpreparative TLC on Si gel (CHCI3) afforded 2(0.012 g), RrO.25 (CHCI3-hexane; 2:1).ReferencesThe Wealth of India: Raw Material, Vol 4 (CSIR, NewDelhi) 1956, p. 139.2 Chaudhuri P K & Thakur R S, Curr Res Med Arom Plants,16, 1994, 5 I.3 Chaudhuri P K & Thakur R S, J Nat Prod, 56, 1993, 51.4 Budzikiewicz H, Wilson H M & Djerassi C, J Am ChernSac, 85, 1963,3688.5 Doddrel D M, Khong P W & Lewis K S, TetrahedronLeu, 1974,2381.6 Cheung H T & Van Y C, Aust J Chern, 25, 1972,2003.7 Hamberger S S, Handa S S, Cordell G A, Kinghorn A D &Farnsworth N R, J Nat Prod, 50, 1987, 281.8 Kodota S, Lami N, Tezuka Y & Kikuchi T, Chern PharmBull, 37,1989,3214.9 Yongxin Z, Dakui L 7 Linzhe L, Planta Medica, 57, 1991,1998.10 Chaudhuri P K, Fitoterapia, 59,1988, 150.

Nonalkaloidal constituents of the seeds of Gloriosa superba

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Nonalkaloidal constituents of the seeds of Gloriosa superba

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