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1.
The roots of Margaretta rosea Oliv., subsp. rosea Bullock contain cardenolides mixed with Kedde negative ester glycosides. 6 Cardenolides were identified by paper chromatography (PC) and thin layer chromatography (TLC). Three of them were free aglycones (uzarigenin ( 1 ), corotoxigenin ( 3 ) and coroglaucigenin ( 5 ), the other three their corresponding 6-deoxy-β-D -allo-pyranosides (ascleposide ( 2 ), gofruside ( 4 ) and frugoside ( 6 ). Only two cardenolides ( 1 and 5 ) were isolated in crystalline form. The behaviour of the more polar portion of the glycoside mixture shows that D -gluco derivatives of at least 5 of the 6 cardenolides mentioned were also present. The Kedde. negative glycosides were a complicated mixture containing mainly 2,6-dideoxysugars linked to esterified polyhydroxy-pregnanes. After mild acid hydrolysis cymarose, oleandrose and digitoxose could be identified by PC and TLC. From the crude aglycone portion only one cristalline genin (M) could be isolated. This was still a mixture, but its main component according to the mass spectrum was a monobenzoyl derivative C28H38O7. - A small amount of cristalline O-acetyl-β-amyrin was isolated from the least polar components. 相似文献
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The roots of Gongronema taylorii are rich in glycosides. These glycosides form a complex mixture of substances, of which some are closely related. From this mixture, six more or less pure but amorphous glycosides could be separated. Mild acid hydrolysis followed by alkaline hydrolysis led to the isolation of 5α-dihydrosarcostin ( 1 ) and some tayloron ( 3 ), whose probable structures have been reported earlier. In the original mixture, these genins are esterified predominantly with benzoic and cinnamic acids, and are also bound through glycosidic linkages to a series of sugars of which the following four could be identified by paper and thin layer chromatography: cymarose, digitoxose, oleandrose and pachybiose. Pachybiose and its two anomeric methyl glycosides have been isolated for the first time in a cristalline state. 相似文献
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Partial formulae have been derived for the nine lilacinosides which were isolated, partly in pure form, and for two related substances which were only obtained as a mixture. These substances are derived basically from two pregnane derivatives (sarcostin and deacetyl-metaplexigenin) present in partially benzoylated form. Of these were isolated genin B = 12,20-di-O-benzoyl-sarcostin ( 1 ), genin C = 12-O-benzoyl-20-O-acetylsarcostin ( 2 ), and genin D, which could be identified with 12-mono-O-benzoyl-desacetyl-metaplexigenin ( 4 ). These three genins are bound to different sugars, the latter being present as mono-, di-, tri- and probably tetra-saccharides. The structures of these were partially derived: after mild hydrolysis three new disaccharides were obtained, which are named asclepobiose (U1), lilacinobiose (U2) and digalilobiose (U5). U1 and U2 were isolated in crystalline form. On hydrolysis U1 yielded 3-O-methyl-6-deoxy-D-allose (U3), U2 yielded 3-O-methyl-6-deoxyglucose (thevetose), and digitalose was obtained from U5. 相似文献
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A new cardenolide and two new pregnane glycosides, periplogenin 3‐[O‐β‐glucopyranosyl‐(1→4)‐β‐sarmentopyranoside] ( 1 ), (3β,20S)‐pregn‐5‐ene‐3,17,20‐triol 20‐[O‐β‐glucopyranosyl‐(1→6)‐O‐glucopyranosyl‐(1→4)‐β‐canaropyranoside] ( 2 ), and (3β,14β,17α)‐3,14,17‐trihydroxy‐21‐methoxypregn‐5‐en‐20‐one 3‐[O‐β‐oleandropyranosyl‐(1→4)‐O‐β‐cymaropyranosyl‐(1→4)‐β‐cymaropyranoside] ( 3 ), were isolated from the root barks of Periploca sepium Bge , together with seven related known compounds, periplogenin, xysmalogenin, (3β,20S)‐pregn‐5‐ene‐3,17,20‐triol, (3β,14β,17α)‐3,14,17‐trihydroxy‐21‐methoxypregn‐5‐en‐20‐one, (3β,20S)‐pregn‐5‐ene‐3,20‐diol 3‐β‐glucopyranoside 20‐β‐glucopyranoside, (3β,20S)‐pregn‐5‐ene‐3,20‐diol 3‐[O‐2‐O‐acetyl‐β‐digitalopyranosyl‐(1→4)‐β‐cymaropyranoside] 20‐[O‐β‐glucopyranosyl‐(1→6)‐O‐β‐glucopyranosyl‐(1→2)‐β‐digitalopyranoside], and (3β,20S)‐ pregn‐5‐ene‐3,20‐diol 20‐[O‐β‐glucopyranosyl‐(1→6)‐β‐glucopyranoside]. Their structures were elucidated on the basis of spectroscopic analyses. 相似文献
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N. I. Uvarova R. P. Gorshkova L. I. Strigina G. B. Elyakov N. K. Kochetkov 《Chemistry of Natural Compounds》1966,1(2):63-66
Summary 1. New glycosides — panaxosides C, D, E, and F — have been isolated from the root of ginseng by partition chromatography.2. The glycosides of ginseng contain genins of two groups: the first consists of the genins of panaxosides A, B, and C, and the second of those of panaxosides D, E, and F. When panaxosides D, E, and F are hydrolyzed, panaxadiol is formed as the main product of the decomposition of the genins.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 2, pp. 82–86, 1965 相似文献
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Summary The structure of the carbohydrate part of panaxoside A has been established by methylation with subsequent hydrolysis and identification of the methylated monosaccharides.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 3, pp. 149–152, 1965 相似文献
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The seeds of Dregea abyssinica (HOCHST .) K. Schum. are very rich in glycosides. These consist of a complicated mixture of ester glycosides, cardenolides are absent. All these glycosides are derived from only the two known pregnane derivatives drevogenin P and Drevogenin D. In the glycosides the latter are esterified with different acids (acetic, isovaleric, α-hydroxyisovaleric and tiglic acid) and glycosidically linked to different 2-deoxy-sugars which in part carry 3-O-methyl-6-deoxy-D-allose and terminal D-glucose. After mild acidic hydrolysis 5 crystalline sugars and 6 crystalline aglycones could be isolated. The sugars were identified as D-cymarose, asclepobiose, pachybiose, drebyssobiose and «sugar T» (formerly found in Dregea volubilis). The following aglycones were obtained: drevogenin A, drevogenin B, and four new compounds called drebyssogenin F, G, J and K. The latter was a mixture of two components (K1 and K2). From the original mixture four genuine glycosides could be isolated (the drebyssosides 1, 2, 3 and 4). Of these the drebyssosides 1 and 3 were obtained crystalline, drebyssoside 2 in amorphous but pure form and drebyssoside 4 as a mixture of mainly two closely related components. The probable structures of the new substances (drebyssobiose, sugar T, the four drebyssogenins and the four drebyssosides) are reported in the following publication. 相似文献
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F Abe M Hirokawa T Yamauchi K Honda N Hayashi R Nishida 《Chemical & pharmaceutical bulletin》1999,47(10):1384-1387
Five new glycosides of 14,15-seco- and 13,14:15-diseco-type pregnanes, including a new pregnane, 2 alpha-hydroxyhirundigenin, were isolated, in addition to one known glycoside, cynatratoside B, from the roots of Tylophora tanakae Maxim. Their structures were elucidated by spectral and chemical means. 相似文献
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The total or partial structure determinations of some new components from Dregea abyssinica are reported. The four drebyssogenins (F, G, J and H) are esters of the drevogenins P ( 7 ) and D( 9 ) and have the following structures: Drebyssogenin F ( 5 ) = 11-O-acetyl-12-O-(α-hydroxyisovaleryl)-drevogenin P, drebyssogenin G ( 14 ) = 11-O-acetyl-12-O-isovaleryl-drevogenin D, drebyssogenin J ( 15 ) = 11, 12-di-O-acetyl-drevogenin D. Drebyssogenin K is a mixture of K1 ( 16 ) and K2 ( 17 ), the mono-O-tiglyl and mono-O-isovaleryl derivatives of drevogenin D respectively, with as yet undetermined position of the acyl residues. The drebyssosides 1, 2 and 3 are glycosides of trisaccharides. Drebyssoside 1 ( 2 ) is pachybiosyl-cymarosyl-drevogenin A, drebyssoside 2 ( 3 ) asclepobiosyl-cymarosyl-drevogenin A and drebyssoside 3 ( 6 ) pachybiosyl-cymarosyl-drebyssogenin F. Drebyssoside 4 is a mixture of at least two components and contains the same aglycones and the same sugar units as the drebyssosides 1 and 3, but is different from them. The full structure of the two sugars (drebyssobiose ( 25 ) and sugar T ( 24 )) has not been determined; it is only shown that both are disaccharides which contain 3-O-methyl-6-deoxy-allose linked to a 2-deoxyhexose. 相似文献
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黑鳗藤中C_(21)甾体苷的分离和结构测定 总被引:4,自引:0,他引:4
从萝藦科植物黑鳗藤[Stephanotis mucronta (Blanco) Merr.]的藤茎中分离 到三个C_(21)甾体去氧糖苷(1) - (3)。通过化学降解和波谱技术,确定它们 的化学结构依次为:12-O-惕各酰基-20-O-乙酰基肉珊瑚苷元3-O-β-黄夹吡喃糖基 -(1→4)-β-磁麻吡喃糖基-(1→4)-β-磁麻吡喃糖苷(1),5,6-双氢-12-O- 乙酰基-20-O-惕各酰基肉珊瑚苷元3-O-β-黄夹吡喃糖基-(1→4)-β-磁麻吡喃糖 基-(1→4)-β-磁麻吡喃糖基(2);12-O-乙酰基-20-O(N-甲基)邻氨基苯甲酰 基肉珊瑚甘元3-O-β-黄夹吡喃糖基-(1→4)-β-磁麻吡喃糖基-(1→4)-β-磁 麻吡喃糖甘(3)。其中1和2为新化合物,分别命名为mucronatoside A, mucrontoside B。3为已知化合物stephanoside E,系首次从该植物中分离得到。 相似文献
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Purification of a Microdesmis keayana hydromethanolic root extract led to the isolation of two new natural compounds, xanthoquininamide (6-hydroxyquinoline-4-carboxamide) and tris(4-hydroxycinnamoyl)spermine (N(5)-(p-coumaroyl)-N(1),N(14)-diferuloylspermine) which was named keayanine. Their structures were determined using spectroscopic analyses (ESI-MS, 1D- and 2D-NMR). 相似文献
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Muhammad Zahid Muhammad Saeed Muhammad Asim Omar Ishrud Shihua Wu ViqarUddin Ahmad Yuanjiang Pan 《Helvetica chimica acta》2003,86(6):2021-2027
From the MeOH extract of Salvia moorcroftiana Wall. (Lamiaceae), four new compounds, the two flavonoid glycosides genkwanin 4′‐[O‐α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐galactopyranoside] ( 1 ) and genkwanin 4′‐[O‐α‐L ‐arabinopyranosyl‐(1→3)‐α‐L ‐rhamnopyranoside] ( 2 ), and the two benzene derivatives 4‐hydroxy‐2‐isopropyl‐5‐methylphenyl O‐α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyranoside ( 3 ) and nonyl 4‐hydroxybenzoate ( 4 ), were isolated in addition to two known compounds. The structures of all new compounds were determined by 1D and 2D homonuclear and heteronuclear NMR spectroscopy and by comparison with published data. 相似文献