β-Amyrin and β-amyrin acetate fromEuphorbia ferganensis

LITERATURE CITED la 2. L. Ruzicka and E. Capato, Helv. Chim. Acta, 8, 259 (1925). M. Nishizawa, H. Takenaka, H. Nishide, and Y. Hayashi, Tetrahedron Left., 2_~4, 2581 (1984). 8-AMYRIN AND 8-AMYRIN ACETATE FROM Euphorbia ferganensis M. M. Tadzhibaev, A. Abdurakhmanov, and K. L. Lutfullin UDC 547.918:547.914.4 We have continued a study of the low-molecular-weight metabolites of the plant B. Fedtsch. (Euphorbiaceae) [i]. Euphorbia ferganensi8 A chloroform extract obtained from an ethanolic extract of the roots of Euphorbia ferganwas chromatographed on a column of silica gel with elution by hexane--benzene (7:1). Crystalline substances (I) and (II) were isolated. ensi8 Substance (I) had mp 195-197°C, [ = ] ~ +89 ± 2 ° (s 1.0; chloroform), M + 426, composition C,oHsoO. Its IR spectrum had the absorption band of a hydroxy group (3460-3400 cm-*). In the strong-field region of its PMR spectrum (CDCIs), the signals of eight methyl groups were observed in the form of singlets and a one-proton quartet at 3.18ppm ('J, = ii and 3j, = 5 Hz)~ assigned to a hemihydroxyllc proton, and also the signal of an 01efinlc proton at 5.14 ppm (triplet with 3j = 3 Hz) of one proton unit. The facts given permit the assumption that substance (I) belongs to the tetracyclic triterpenoids of the olean-12-ene series. This was also shown by the mass-spectrometrlc fragmentation of compound (I), which was characteristic for pentacyclic triterpenoids [2]. The peaks of ions with m/z 218 and 207 arising as a consequence of retrodiene decomposition appeared in the mass spectrum. The spectral characteristics and physicochemical constants of substance (I) showed its identity as 8-amyrin [3]. Substance (II) had mp 233-235°C, [ e ] ~ +75 ± 2 ° (s 1.3 benzene), M + 468, composition C,2Hs=O2. The IR spectrum of the compouna showedabsorption bands of an ester group (1735, 1260 cm-*). The PMR spectrum of substance (II) (CDCl,), having a three-proton singlet at 2.01 ppm, showed that it contained one acetyl group. The alkaline hydrolysis of substance (II) with 0.5% methanollc potassium hydroxide at room temperature led to a product identified as 8-amyrin from physicochemical constants and also from its Rf values on TLC in various solvent systems. Thus, 8-amyrin and S-amyrin acetate have been isolated from the roots of Euphorbia fer- ganensis. LITERATURE CITED . 2. 3. M. M. Tadzhibaev and K. L. Lutfullin, Khim. Prir. Soedin., 571 (1985). J. Karliner and C. Djerassi, J. Org. Chem., 31, 1945 (1966). R. Tschesche and G. Wulff, Fortschr. Chem. Org. Naturstoffe, 30, 461 (1973). M. I. Kalinin Andizhan State Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 6, p. 794, November-December, 1986. Original article submitted June 23, 1986. 738 0009-3130/86/2206-0738512.50 O 1987 Plenum Publishing Corporation  (...truncated)