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11.
N. Z. Mamadalieva Z. Saatov V. V. Kachala A. S. Shashkov 《Chemistry of Natural Compounds》2002,38(2):179-181
The new ecdysteroid 2-deoxyecdysterone-25-acetate was isolated from roots of Silene wallichiana Klotzsch. 相似文献
12.
V. S. Strigunov V. I. Grishkovets A. S. Shashkov V. Ya. Chirva 《Chemistry of Natural Compounds》2001,37(5):462-465
Minor monodesmoside triterpene glycosides St-A, St-B, St-C
1
, St-D
1
, St-C
2
, and St-D
2
were isolated from stem bark ofTetrapanax papyriferumC. Koch (Araliaceae). The structures of oleanolic and echinocystic acid 3-O--L-arabinopyranosides, oleanolic and echinocystic acid 3-O--D-glucopyranosyl-(13)-O--L-arabinopyranosides, and oleanolic and echinocystic acid 3-O--D-galactopyranosyl-(12)-O--L-arabinopyranosides, respectively, were proposed. Glycosides St-C
2
, St-D
1
, and St-D
2
are new triterpene glycosides. The structures of the isolated compounds were established using chemical methods and NMR spectroscopy. 相似文献
13.
14.
V. I. Grishkovets A. E. Kondratenko N. V. Tolkacheva A. S. Shashkov V. Ya. Chirva 《Chemistry of Natural Compounds》1995,30(6):689-692
The leaves of common ivy have yielded 11 triterpene glycosides: the 3-O--L-pyranosides of oleanolic acid (1), of echinocystic acid (2), and of hederagenin; the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside]s of oleanolic acid (4), of echinocystic acid (5), and of hederagenin (6); the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O--L-pyranoside (7); the O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ester of hederagenin 3-O-[O--L-pyranosyl-(12)--L-arabinopyranoside] (9); and the O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl esters of oleanolic acid, echinocystic acid, and hederagenin 3-O-[O--L-rhamnopyranosyl-(12)--D-glucopyranoside]s (8), (10), and (11), respectively. This is the first time that compounds (1), (2), (5), (7), (9), and (10) have been found in this plant.Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 742–746, November–December, 1994. 相似文献
15.
Siberian Mathematical Journal - We address the unital right alternative bimodules over the matrix algebras $ {\mathrm{M}}_{n}(\Phi) $ of order $ n\geq 3 $ , prove that each of these... 相似文献
16.
17.
高效液相色谱氮杂冠醚键合固定相的合成及性能研究 总被引:2,自引:0,他引:2
我们曾用γ-氯丙基键合硅胶(CPS),在氢化钠(NaH)作用下合成了3-(氮杂-18-冠-6)丙基键合固定相(BCP)[1].该固定相对碱基、核苷酸、硝基苯酚等有较好的分离选择性,但由于NaH对硅胶基质腐蚀作用较大,导致BCP柱效及渗透性较低.本文采... 相似文献
18.
V. I. Grishkovets V. S. Strigunov A. S. Shashkov V. Ya. Chirva 《Chemistry of Natural Compounds》2001,37(2):167-172
Stem bark ofTetrapanax papyriferumC. Koch., Araliaceae, yielded new triterpene glycosides 28-O--L-rhamnopyranosyl-(14)-O-(6-O-acetyl--D-glucopyranosyl)-(16)-O--D-glucopyranosyl esters of the 3-O-[-D-glucopyranosyl-(13)-[-D-galactopyranosyl-(12)]-O--L-arabinopyranosides of oleanolic and echinocystic acids. The structures of these substances were established using chemical and physicochemical methods 相似文献
19.
D. A. Rakhimov A. S. Shashkov K. S. Zhauynbaeva M. Kh. Malikova N. D. Abdullaev 《Chemistry of Natural Compounds》2004,40(4):358-361
Native acetylated glucomannan of molecular weight (MW) 32000 with a glucose:mannose ratio 1:30 was isolated from bulbs of Narcissus poeticus. Glucomannan was depolymerized to a fragment of MW 15000 with an unchanged primary structure and was studied using PMR and 13C NMR spectroscopy. It was found that the linear chain of the biopolymer consists of 1-4-bound D-gluco- and D-mannopyranose units and the O-Ac groups are localized on C-2, C-3, and C-6 hydroxyls in certain anhydromannose units. 相似文献
20.
Yu. S. Vollerner S. D. Kravets A. S. Shashkov M. B. Gorovits N. K. Abubakirov 《Chemistry of Natural Compounds》1988,24(2):183-186
A new genin of the spirostan series — anzurogenin B having the structure of 2,5-epoxy-(25R)-spirostan-3,6-diol — has been isolated form the collective fruit of the cocultivatedAllium suvorovii Rgl. andAllium stipitatum Rgl. (family Liliaceae).Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 218–221, March–April, 1988. 相似文献