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T. G. Sagareishvili B. L. Grigolava N. E. Gelashvili E. P. Kemertelidze 《Chemistry of Natural Compounds》2000,36(4):360-361
Essential oil (1.1%) is isolated fromSalvia officinaliscultivated in Georgia. Its properties are:
20
0.921, n
D
20
1.463, []
D
20
+24.91 , acid number 2.8, ketone content 65.4% (oxime method). GLC showed the presence of 11 terpenes, among which -thujone (31.56%), -thujone (17.55), camphor (16.48), and 1,8-cineol (17.53) are present in the highest amounts. 相似文献
115.
M. M. Benidze O. D. Dzhikiya T. A. Pkheidze É. P. Kemertelidze A. S. Shashkov 《Chemistry of Natural Compounds》1988,23(4):448-452
Two new steroid glycosides have been isolated from the leaves of aloe yucca and their structures have been established. Glycosides B and C are tigogenin penta-and hexaosides. Glycoside B, which we have called yuccaloeside B is (25R)-5-spirostan-3-ol 3-{[O--D-glucopyranosyl-(12)]-[O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(13)]-O--D-glucopyranosyl-(14)--D-galactopyranoside}, and glycoside C, which we have called yuccaloeside C is (25R)-5-spirostan-3-ol 3-{[(O--D-glucopyranosyl-(13)-O--D-glucopyranosyl-(12)]-[O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(13)]-O--D-glucopyranosyl-(14)--D-galactopyranoside}.N. G. Kutateladze Institute of Pharmacochemistry of the Georgian SSR Academy of Sciences, Tbilisi. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 537–542, July–August, 1987. 相似文献
116.
Gloriosaols A (1) and B (2), two novel phenolic derivatives characterized by unusual spirostructures made up of two C15 units linked via a γ-lactone to a central stilbenic portion were isolated from the roots of Yucca gloriosa. On the basis of an extensive NMR analysis, the same basic structure was established for the two compounds but no further information about their structural difference could be deduced. Thus two hypotheses were formulated: (1) gloriosaols A and B could be atropisomers caused by a restriction of the free rotation around the double bond due to a steric congestion of the bulky phenolic portions; (2) gloriosaols A and B could be two configurational isomers, indicating, in this case, a nonstereoselective biogenetic formation of the stereogenic center C-2. Semi-empirical calculations of the potential energy surfaces on gloriosaols A and B, together with the 1H NMR spectra recorded at various temperatures, allowed us to unambiguously exclude the hypothesis of two restricted rotational conformers of a single configurational isomer. Finally, quantum mechanical calculations of the geometries and of the 1H chemical shifts on the gloriasols A and B in combination with the analysis of the ROE data allowed us to deduce a diastereomeric relation between the two compounds and to assess the relative configuration of the two diastereomers. 相似文献
117.
A method has been developed for isolating and purifying lectin fromBryonia albaroots. Proteins with molecular weights from 45 to 67 kDa dominate in the partially purified lectin. The carbohydrate selectivity places the lectin in the galactose-specific group. 相似文献
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M. I. Merlani L. Sh. Amiranashvili M. G. Davitishvili E. P. Kemertelidze K. Papadopoulos E. Yannakopoulou 《Chemistry of Natural Compounds》2006,42(2):194-197
A series of new isonicotinylhydrazones and thiosemicarbazones of various ketosteroids was synthesized. The structures of the
compounds were confirmed by NMR and IR spectroscopy and mass spectrometry.
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Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 160–163, March–April, 2006. 相似文献