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1.
S. A. Mamedova 《Chemistry of Natural Compounds》1994,30(2):267-268
Institute of Botany, Academy of Sciences of the Republic of Azerbaidzhan, Baku. Translated from Khimiya Prirodnykh Soedinenii,
No. 2, pp. 291–292, March–April, 1994. 相似文献
2.
3.
I. A. Sukhina R. P. Mamedova M. A. Agzamova M. I. Isaev 《Chemistry of Natural Compounds》2007,43(2):159-161
The two trisdesmoside cycloartane glycosides astragaloside VII and cyclotrisectoside were isolated from Astragalus dissectus (Leguminosae) and identified. The latter was 20R,25-epoxy-24S-cycloartan-3β,6α,16β,24-tetraol 3-O-β-D-xylopyranoside-6,24-di-O-β-D-glucopyranoside and was a new natural compound.
Presented at the Sixth International Symposium on the Chemistry of Natural Compounds (SCNC, Turkey, Ankara, 28–29 June 2005).
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 132–134, March–April, 2007. 相似文献
4.
D. B. Tagiev P. S. Mamedova F. A. Abdullaeva M. K. Munshieva A. A. Turabova T. G. Takhirov 《Russian Chemical Bulletin》1992,41(11):2113-2115
The catalytic activity of Ni(II) bis-(5-thiopyrazol-4-aldiminates) was found to be related to the stereochemical flexibility of these compounds in the dimerization of propylene. The propylene conversion decreases with decreasing stereochemical flexibility of the complexes resulting from an increase in the bulk of the substituent at the coordinated nitrogen atom of the NiN2S2 chelate ring.Institute of Inorganic and Physical Chemistry, Academy of Sciences of Azerbaidjan, 370143 Baku. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2667–2670, November, 1992. 相似文献
5.
A. T. Shakhtakhtinskaya Z. M. Mamedova Sh. F. Mutallibova S. Z. Alieva R. G. Mardzhanova 《Reaction Kinetics and Catalysis Letters》1989,39(1):137-140
Acidity of catalyst surfaces of different nature such as -Al2O3, natural zeolite-clinoptilolite, and synthetic zeolite zeokar by adsorption of ammonia over a wide temperature range has been studied. Ammonia is adsorbed on the catalysts with different strengths, as evidenced by the presence of different types of acid sites.
(-Al2O3, - , () . , , .相似文献
6.
The new triterpene glycoside cycloorbicoside C was isolated from the aerial parts of Astragalus orbiculatus Ledeb. (Leguminosae) and was identified as (23R,24S)-16,23;16,24-diepoxycycloartan-3,25-diol 3-O--D-xylopyranoside 25-O--D-glucopyranoside. 相似文献
7.
S. G. Mamedova N. Sh. Rasulov Z. M. Rzaev 《Journal of polymer science. Part A, Polymer chemistry》1987,25(2):711-717
Some regularities of radical alternating copolymerization of maleic anhydride with allyl chloroacetate are studied. The formation of donor–acceptor complexes between comonomers with complexing constant Kc = 0.052 L/mol is found using 1H NMR spectroscopy. The kinetic parameters for this copolymerization reaction are found and the quantitative contribution of monomer complexes to chain-growth radical reactions is calculated. It is shown that either a “free-monomer” mechanism (dilute solutions) or a “mixed” mechanism (concentrated solutions) prevails for chain growth during radical copolymerization depending on total monomer concentration. It is found that inhibition of degradative chain transfer in the course of the reaction studied takes place owing to the presence of α-chlorine atom in the allyl chloracetate molecule and formation of charge transfer complex. 相似文献
8.
The new triterpenoid cycloartane cycloorbigenin C, the structure of which is 23ξ,24ξ-cycloartan-3β,6α,16β,23,24,25-hexaol, was obtained from the aerial part of Astragalus orbiculatus Ledeb. (Leguminosae). The structure of cycloorbigenin C was proved using chemical transformations, IR spectroscopy, electron-impact mass spectrometry, and PMR and 13C NMR spectra interpreted using J-modulation and the 2D NMR spectroscopies: 1H-1H COSY, TOCSY, ROESY, HSQC, and HMBC. 相似文献
9.
Besada P Mamedova L Thomas CJ Costanzi S Jacobson KA 《Organic & biomolecular chemistry》2005,3(10):2016-2025
Diketopiperazines (DKPs) are a common motif in various biologically active natural products, and hence they may be useful scaffolds for the rational design of receptor probes and therapeutic agents. We constructed a new bicyclic scaffold that combines a DKP bridged with a 10-membered ring. In this way we obtained a three-dimensional molecular skeleton, with several amendable sites that provide a starting point to design a new combinatorial library having diverse substituent groups. Structural variation is based upon the flexibility of alkylation of the nitrogen atoms of the DKP and on the side-chain olefin. We obtained a 10-membered secondary ring through a ring-closure metathesis reaction using the second generation Grubbs catalyst. Rings containing both O-ethers and S-ethers were compared. N-Alkyl or arylalkyl groups were introduced optionally at the two Nalpha-atoms. This is a general scheme that will allow us to test rings of varying sizes, linkages, and stereochemical parameters. The DKP derivatives were tested for activity in astrocytoma cells expressing receptors coupled to phospholipase C. Inhibitory effects were observed for signaling elicited by activation of human nucleotide P2Y receptors but not m3 muscarinic receptors. Compound 20 selectively inhibited calcium mobilization (IC50 value of 486 +/- 16 nM) and phosphoinositide turnover elicited by a selective P2Y1 receptor agonist, but this compound did not compete for binding of a radiolabeled nucleotide-competitive receptor antagonist. Therefore, the new class of DKP derivatives shows utility as pharmacological tools for P2Y receptors. 相似文献
10.
S. Sh. Mamedova S. R. Gadzhieva T. G. Khanlarov 《Russian Journal of Inorganic Chemistry》2008,53(12):1964-1966
Conditional stability constants of metal complexes with synthesized copolymers are studied by potentiometric titration. Linear copolymers are found to form more stable complexes than cross-linked sorbents with analogous functional groups. The stability of these complexes decreases in the order Th(IV) > Fe(III) ≈ La(III) > Cu(II). 相似文献