tailieunhanh - Chemical constituents of zizyphus sativa gaertn fruits: III - Alkaloids

Two alkaloids have been isolated from Z. sativa fruits besides butane-2,3-diol and glycerol. The structures of alkaloids were established as stepharine and 1,2-dimethoxy,5,6,6a,7-tetrahydro- 4H-dibenzo-quinoline by using MS, NMR spectroscopic data and by comparison with reported data. | Journal of Chemistry Vol. 45 2 P. 237 - 240 2007 CHEMICAL CONSTITUENTS OF ZIZyPHUS SATIVA GAERTN FRUITS III - ALKALOIDS Received 29 June 2006 NGUyEN THI HOANG ANH1 TRAN VAN SUNG1 NOBERT ARNOlD2 L. WESSJQHANN2 institute of Chemistry Vietnamese Academy of Science and Technology 2Leibniz Institute of Plant Biochemistry Halle Saale Germany SUMMARy Two alkaloids have been isolated from Z. sativa fruits besides butane-2 3-diol and glycerol. The structures of alkaloids were established as stepharine and 1 2-dimethoxy 5 6 6a 7-tetrahydro-4H-dibenzo-quinoline by using MS NMR spectroscopic data and by comparison with reported data. I - INTRODUCTION Some species of Zizyphus genus Rhamnaceae have been used for treatment of biliousness chronic bronchitis blood diseases or as analeptic expectorant 1 . Zizyphus species have been known as a rich source of cyclopeptide alkaloids 2 3 . In a previous article 4 we reported the separation and structural elucidation of triterpene acids from Zizyphus sativa fruits. This paper concerns the isolation and structural determination of two alkaloids and two common compounds. Their structures have been elucidated as stepharine 1 1 2-dimethoxy 5 6 6a 7-tetrahydro-4H-dibenzoquinoline 2 butane-2 3-diol 3 and glycerol 4 by using spectroscopic methods. II - EXPERIMENTAL 1. Plant material The fruits of Z. sativa were bought in the traditional medicine market in Hanoi in May 2005. A voucher specimen Nr. was deposited in the Herbarium of Institute of Chemistry. 2. Instruments and Chemicals NMR Varian Unity 300 MS AMD 402 for analytical purposes Merck TLC aluminium sheets silica gel 60 F254 layer thickness mm were used. Silica gel Merck 60 - mm is used for column chromatography. 3. Extraction and Isolation Air dried and powdered fruits of Z. sativa kg were extracted with EtOH H2O 95 5 at room temperature. The obtained ethanol extract was dissolved in 5 HCl solution and then extracted with n-hexane. The aqueous phase was .