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Two new naphtho-pyrone glycosides, 9-[(beta-D-glucopyranosyl-(1----6)-O-beta-D-glucopyranosyl)oxy]-10- hydroxy-7-methoxy-3-methyl-1H-naphtho[2,3-c]pyran-1 -one (5) and 6-[(alpha-apiofuranosyl-(1----6)-O-beta-D-glucopyranosyl)oxy]- rubrofusarin (6), together with cassiaside (3) and rubrofusarin-6-beta-gentiobioside (4) were isolated from the seeds of Cassia tora L. Their structures were elucidated on the basis of chemical and spectral data. The naphtho-gamma-pyrone glycosides (3, 4, and 6) were found to have significant hepato-protective effects against galactosamine damage, which were higher than that of silybin from Silybum marianum.

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F a c u l a de F a d i a , Universia Federal do RioG r a d do SUI, Av. Ipirange, 2752, 90610 Port0 Alegre, RS, Brad and 0. SELIGMANN lnstitut f f i Phannazuttirche Siologie &r Unimikit Miinrhm, Karlstrase 29, D-8000 Mumben 2, West G m n y Assmcr.-Matesaponin 1, a new saponin obtained from the leaves of Ilexparaguarimsis, has been characterized by 'H nmr, 13C nmr, eims, fabms, and chemical reactions. The structure has been determined as ursolic acid-3-0-[f3-~-glucopyranosyl-( 1e3)-a-~-arabincpyranosyl)-(28~ l)-~-D-g~ucopyranosy~ ester.Ilex paraguariensis St. Hil. (Aquifoliaceae) is widely used as a traditional beverage known as mate (Paraguay tea) in southern Brazil, Argentina, Paraguay, and Uruguay. It is also used in popular medicines and employed in commercial herbal preparations as a stimulant to the central nervous system, a diuretic, and an antirheumatic. Apart from the wellknown xanthines, very little is known about its secondary metabolites (1). This paper reports the isolation and elucidation of the structure of a new saponin, named matesaponin 1, from the leaves of this medicinal plant.Matesaponin 1 was obtained from the n-BuOH extract through cc. After acid hydrolysis, the sugar components were identified as glucose and arabinose by tlc, whereas the identity of the aglycone moiety as ursolic acid was confirmed byThe eims of the acetyl derivative of matesaponin 1 showed peaks at mlz 438 and 331, which were attributed to the aglycone and the terminal hexose, respectively.The molecular mass of matesaponin 1 was shown to be 912 through fabms, which exhibited molecular ion peaks at m/z919EM+Li)+ and935 [M+Na]+. The fab mass spectrum, obtained in the negative ion mode, confirmed the molecular mass and gave information about the sequence of the sugars by the peaksatmlz911EM-H)-, 749[(M-H) -hexose)-, 587 [(M -H -hexose) H and 13C nmr (2-5). 1 -hexose)-, and 455 [(M -H -hexose -hexose) -pentose)-.The 'H-nmr spectrum of the acetyl derivative of matesaponin 1 showed three anomeric proton signals at 6 4.63 pprn (d,],,, = 8 Hz) and 6 4.3 1 ppm (d, ]1,2 = 8 Hz) attributed to glucose and arabinose, respectively, at C-3, and at 6 5.53 pprn (d,J1,,=8 Hz) corresponding to glucose at C-28 (6). These assignments were supported by the 13C-nmr spectrum of matesaponin 1, which showed three anomeric proton signals at 6 (pprn) 107.2, 106.0, and 95.5, the latter in full agreement with the presence of a f3-glucopyranose linked in the form of an ester (7-9). The f3 configuration for the two glucopyranosyl units and the CY configuration for the arabinopyranoside were inferred from the] values of the respective anomeric protons.The interglycosidic linkage was determined by the observed downfield shift (A6 9.3) for C-3 of the inner a-Larabinose, by comparing with the corresponding methylglycoside (10). This deshielding clearly indicated that the terminal glycosyl unit is attached at this position; the rest of the carbons were unaffected (Table 1).Matesaponin 1 on partial hydrolysis afforded a prosapogenin. Its fabms spectrum indicate...

From the leaves and stems of Viscum album L., syringenin 4'-O-glucoside (syringin), syringenin 4'-O-apiosyl-l -2-glucoside, syringaresinol 4', 4'-di-O-glucoside (eleutheroside E) and syringaresinolmono-O-glucoside were isolated. The isolated compounds are suitable for the HPLC-fingerprint analysis of alcoholic or aqueous Viscum album extracts. A butanol extract, containing these compounds showed a significant cAMP-phosphodiesterase inhibitory activity.