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11.
In addition to known ecdysteroids (2-deoxy--ecdysone and 2-deoxyecdysterone) fromSilene praemixta (Caryophyllaceae) we have isolated new ones — premixisterone and selenosterone (I), C27H42O7, mp 115–117°C (from MeOH), []
D
28
+86.9 ± 2° (c 0.92, MeOH), yield 0.003%. The acetylation of (I) with (CH3CO)2O in Py gave 22-acetyl-selenosterone (II), C29H44O6, mp 210–212°C (MeOH-C6H14), []
D
27
+45.5 ± 3° (c 0.16; MeOH). On the basis of physiocochemical and spectral characteristics it has been established that (I) has the structure of 14,22R,25-trihydroxy-5-cholest-7-ene-3,6-dione. The IR, PMR, and mass spectra of (I) and (II) are presented.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 793–797, November–December, 1979. 相似文献
12.
We analyzed the possibility of improving the efficiency of microwave devices operating with relativistic electron beams in systems with particle postacceleration in the interaction space. The fundamental feature of this approach is the formation of the accelerating-potential profile with the inherent electric field of a high-current electron beam. It is shown that the use of the space-variant beam-potential sag helps raise the estimated efficiencies of relativistic Cherenkov TWT and BWO up to values of about 50%. 相似文献
13.
R. N. Tursunova V. A. Maslennikova N. K. Abubakirov 《Chemistry of Natural Compounds》1981,17(2):145-149
Two withanolides have been isolated from the epigeal part ofPhysalis viscosa L. One of them with the compositions C28H38O8 has been identified as 4-hydroxy-withanolide E, and for the second, which has been called physanolide, the structure of 14,17,20R-trihydroxy-1,4-dioxo-22R-witha-5,24-dienolide has been proposed on the basis of its UV, IR, PMR, and mass spectra, and also the results of a partial synthesis of 14-hydroxyandrost-5-ene-1,4,17-trione, obtained by its oxidation.Institute of the Chemistry of Plant Substances, Academy of Sciences of Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 187–192, March–April, 1981. 相似文献
14.
Sh. A. Alieva Zh. M. Putieva E. S. Kondratenko N. K. Abubakirov 《Chemistry of Natural Compounds》1978,13(5):546-549
Summary Six new diterpene glycosides — doronicosides A, B, C, D, E, and F — have been detected in the roots ofDoronicum macrophyllum Fisch. The qualitative and quantitative composition of the sugar chain of doronicoside D has been established. It has been shown that the negative aglycone of all the doronicosides is 15-hydroxy-(–)-kaur-16-en-19-oic acid, which, in the process of hydrolysis, is converted into 15-oxo-(–)-kauran-19-oic acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. N. Narimanov Azerbaidzhan State Medical Institute, Baku. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 658–662, September–October, 1977. 相似文献
15.
A new phytoecdysteroid, 2-deoxy-α-ecdysone 22-O-benzoate, has been isolated from the epigeal organs ofSilene wallichiana Klotzch. 相似文献
16.
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
17.
T. V. Ganenko M. I. Isaev A. S. Gromova N. D. Abdullaev A. A. Semenov M. B. Gorovits N. K. Abubakirov 《Chemistry of Natural Compounds》1986,22(3):315-319
A new glycoside (cyclofoetoside B) (I) has been isolated from the epigeal part of the plantThalictrum foetidum L. (Ranunculaceae). On the basis of chemical transformations and with the aid of physicochemical characteristics it has been established that cyclofoetoside B is 24S-cycloartane-3, 16, 24, 25, 29-pentaol 3-O--L-arabinopyranoside 16-O-[O--L-rhamnopyranoside-(1 6)--D-glucopyranoside], C47-H80O17, mp 194–197°C (methanol); []
D
24
+15.7 ± 2° (c 0.88; pyridine). The enzymatic hydrolysis of (I) has yielded cyclofoetigenin B (III), 24S-cycloartane-3,16,24,25,29-pentaol 16-O--D-glucopyranoside, (IV), C36H62O10, mp 223–225°C (acetone), []
D
24
+37 ± 2° (c 0.97; methanol) and 24S-cycloartane-3,16,24,25,29-pentaol 16-O-[O--L-rhamnopyranosyl-(1 6)--D-glucopyranoside, C42H72O14, mp 229–231°C (methanol), []
D
30
+41 ± 2° (c 0.7; methanol). Details of the IR and1H and13C NMR spectra of the compounds are given.Irkutsk Institute of Organic Chemistry, Academy of Sciences of the USSR. Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Trashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 341–345, May–June, 1986. 相似文献
18.
C. D. Kravets Yu. S. Vollerner M. B. Gorovits A. S. Shashkov N. K. Abubakirov 《Chemistry of Natural Compounds》1986,22(5):553-556
A new steroid glycoside — alliospiroside B (I) — has been isolated from the collective fruit ofAllium cepa L. On the basis of chemical transformations and with the aid of physicochemical measurements it has been established that compound (I) has the structure of (25S)spirost-5-ene-1β,3β-diol 1-O-[O-α-L-rhamnopyranosyl-(1 → 2)-β-D-galactopyranoside. Compound (I) C39H62O3, mp 200–202°C (from ethanol). [α] D 20 ?110.9±2° (c 1.01; pyridine) was obtained by extracting the collective fruit ofA. cepa with ethanol folowed by the column chromatographic separation of the combined glycosides on silica gel. The acid hydrolysis of (I) gave (25S)-ruscogenin (II), C27H42O4, mp 189–191°C, [α] D 23 ?104.1±2° (c 0.98; pyridine). The1H and13C NMR spectra are given for both compounds and the IR spectrum for compound (I). 相似文献
19.
On the basis of chemical transformations and with the aid of physicochemical results, the structure of glycoside I isolated from the roots of the plantMedicago sativa has been established as hederagin 3-O-[O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 2)-α-L-arabinopyranoside] 28-O-β-D-glucopyranoside. Compound (I), C52H84O22, mp 210–212°C, [α] D 21 +38.4° (c 1.48; methanol). Acid hydrolysis of (I) led to hederogenin (II) — C30H48O4, mp 326–330°C, [α] D 23 +84.2° (c 0.19; pyridine. The Hakomorimethylation of glycoside (I) yielded the permethylate (IV) — C65H11O22 [α] D 23 +41.6° (c 1.79; methanol). The GLC analysis of the products of the methanolysis of compound (IV) showed the presence of 3,4,6-tri-O-methyl-D-glucopyranose, 2,3,4,6-tetra-O-methyl-D-glucopyranose, 3,4-di-O-methyl-L-O-arabinopyranose, and 2,3,4-tri-o-methyl-L-arabinopyranose. The alkaline hydrolysis of glycoside I gave compound (III) with mp 230–233°C, [α] D 21 +35.2° (c 0.21; methanol), which was identified as medicoside C. Details of the PMR spectrum are given for compound (IV) and of the IR spectrum for compound (I). 相似文献
20.
The circular dichroism method has been used to establish the stereochemical features of the structure of the withasteroids.
The 22S-configuration of the asymmetric center has been confirmed for physangulide. The 22R-configuration has been confirmed
for 14α-hydroxyixocarpanolide, vamonolide, ixocarpanolide, 24,25-epoxywithanolide D, and withanolide T. On the basis of changes
in the circular dichroism spectra in acid and alkaline media it is suggested that in compounds having a 4β-hydroxy-1-oxo-5β,6β-epoxy-2,3-ene
grouping the Δ2,3 bond disappears, while in compounds having a 5α-hydroxy-1-oxo-6α,7α-epoxy-2,3-ene grouping dehydration takes place at C-4-C-5.
These characteristics can be used in the identification of the withasteroids. The isolation of withanolide T from the leaves
ofPhysalis angulata L. is described and its spectral characteristics are given.
Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh
Soedinenii, No. 3, pp. 371–376, May–June, 1990. 相似文献