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1.
Russian Physics Journal - The specific features of the sorption activity of silver nanoparticles (AgNPs) on biodegradable polymers of natural (collagen) and artificial (polyamide 6.6) origin have...  相似文献   
2.
JETP Letters - The possibility of stable generation of intense characteristic Cs radiation upon electronic excitation of a Mo anode target heat treated in Cs and O2 vapors is demonstrated. The...  相似文献   
3.
4.
Cascade heterocyclization of 3(4)-methylcyclohexanone, substituted benzaldehyde, and 2-naphthyl-amine in a polar solvent in the presence of hydrochloric acid afforded the corresponding 5-aryl-2(3)-methyl-1,2,3,4-tetrahydrobenzo[a]phenanthridines and 12-aryl-9(10)-methyl-8,9,10,11-tetrahydrobenz[a]acridines  相似文献   
5.
The crystal and molecular structures of 2,10-diacetoxy-13-thiabicyclo[7.3.1]-cis-tridec-5-ene and 2,9-dichloro-13-thiablcyclo[8.2.1]-cis-tridec-5-ene sulfoxide were established. The conformations of the molecules are such that the unshared pairs of electrons of the sulfur atoms are directed to the carboncarbon double bonds of their molecules. It was observed that there are stereochemical conditions for transannular transformations under the influence of polarized molecules and cations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1628–1632, December, 1977.  相似文献   
6.
Two furofuranoid lignan glycosides, having the structures of (+)-syringaresinol 4′,4″-di-β-D-glucopyranoside (1) and (+)-syringaresinol 4′-β-D-glucopyranoside (2), and also 2-methylbut-3-en-2-yl β-D-glucopyranoside (3), have been isolated from an extract of the leaves ofNolina microcarpa (fam. Dracaenaceae).  相似文献   
7.
The pentasaccharide α - Tyv - (1→3) - β - d - Man - (1→4) - α - l - Rha - (1→3) - d - Gal - (4←1) -α - d - Glc 1, the repeating unit of the O-specific polysaccharide chain of the lipopolysaccharide from S. Strasbourg, was obtained by glycosylation of benzyl - 2,6 - di - O - benzyl - 4 - O - (2,3,4 - tri - O - benzyl - 6 - O - benzoyl - α - d - glucopyranosyl) - β - d - galactopyranoside with 1,2 - methylorthoacetyl - 3 - O - acetyl - 4- O - [3 - O - (2,4 - di - O - acetyl - 3, 6 - dideoxy,- α - d - arabino - hexopyranosyl) - 2,4,6 - tri - O - acetyl - β - d - mannopyranosyl] - β - l - rhamnopyranose 3 followed by removal of protecting groups. The structure of the synthetic pentasaccharide was proved by methylation analysis and 13C NMR.  相似文献   
8.
Two new glycosides which have been called nolinofurosides G(I) and H(III), have been isolated from the leaves ofNolina microcarpa. Nolinofuroside G is the sodium salt of 26-β-D-glucofuranosyloxy-(25S)-furost-5,20(22)-diene-1β, 3β-diol 1-sulfate, and nolinofuroside H is the sodium salt of 1-β-D-fucopyranosyloxy-26-β-D-glucopyranosyloxy-(25S)-furost-5,20(22)-dinen-1β-3β-ol 3-sulfate. M. V. Frunze Simferopol' State University. Institute of the Chemistry of Plant Substances, Uzbek. Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 801–806, November–December, 1991.  相似文献   
9.
The new ecdysteroid 2-deoxyecdysterone-25-acetate was isolated from roots of Silene wallichiana Klotzsch.  相似文献   
10.
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   
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