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1.
We have used 31P NMR (MAS) and IR spectroscopy and also chemical analysis to show that when Si- and Ti,Si-MCM-41 mesoporous molecular sieves are treated with phosphorus oxychloride, surface-anchored silicophosphate and titanophosphate compounds are formed of the type (Si—O) x —{PO(OH)3–x } and (Ti—O) x —{PO(OH)3–x } (x = 1, 2), and also compounds with the structure of titanium hydrophosphate and pyrophosphate.  相似文献   

2.
Two alkaloids of a new type — komarovine and komarovidine — have been isolated from the epigeal part of theNitraria komarovii. Their structures — 3-(quinolin-8'-yl)--carboline and 3-(quinolin-8'-yl)-5,6-dihydro--carboline, respectively — have been established by synthesis.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 192–195, March–April, 1981.  相似文献   

3.
The synthesis and characterization of the oxo-centered carboxylato-bridged trinuclear iron(III) complex, triaquahexakis(2-betaine)(3-oxo)triiron(III) perchlorate heptahydrate are described. X-ray crystallography shows that the FeIII atom in the complex has a slightly distorted octahedral geometry, coordinated by four oxygen atoms from different betaine ligands [Fe—;O = 2.009(3) 2.034(3) Å], one aqua ligand [Fe—O = 2.028(4) and 2.031(3) Å] and the central 3-oxo atom [Fe—O = 1.917(2) and 1.917(3) Å]. The central oxygen is ideally coplanar with the plane of the three metal atoms. Magnetic susceptibility data (4–320 K) show the presence of an antiferromagnetic exchange interaction with a coupling constant of J = –20.2 cm–1.  相似文献   

4.
Summary The alkaloids ofMerendera iolantae E. Czerniak have been studied for the first time. The total alkaloids consist of tropolone compounds and bases without a tropolone ring. From this plant we isolated the known alkaloids colchicine, colchamine, -lumicolchicine, colchameine, and 2-demethylcolchiceine, and four new, nontropolone, bases — MI-1 (iolantamine), MI-2, MI-3, and MI-4. The presence of colchiceine, 3-demethylcolchamine, and two unknown bases with R f 0.49 and 0.53 was shown by chromatographic methods.A developed formula has been put forward for iolantamine on the basis of its spectral characteristics.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 487–493, July–August, 1972.  相似文献   

5.
The molecular and crystalline structures of the diterpene alkaloid delcosine (iliensine) have been investigated by x-ray structural analysis. It has been confirmed that the OH group in ring A is located at C(1) and has the orientation. The rings in the molecule have the following conformations: A, B, and D — boat; C and F — envelope; E — chain. The ring linkages are: A/B — trans; A/E — cis; B/C — cis; B/D — cis; B/F — cis. The conformations and linkages of the rings are identical with those observed in lycoctonine.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 754–758, November–December, 1983.  相似文献   

6.
An optical-fiber sensor for colchicine has been fabricated. It is based on the use of the fluorescent dye N-vinylcarbazole, which contains a vinyl unit making it photo-copolymerizable in the presence of a monomer, 1,2-cyclohexanediol diacrylate, on a quartz surface of an optode slide. Prior to the photo-polymerization process the quartz surface was modified with -(methacryloxy)propyl trimethoxysilane to introduce vinyl units. A dye-incorporating optode membrane tightly immobilized on the quartz surface was prepared in this way. The spectral characteristics of the optode for sensing colchicines were evaluated, and the response mechanism was discussed. The optode membrane has a relatively long lifetime and short response and recovering time. The linear range of determining colchicine is from 1.0×10–6 to 4.0×10–3molL–1. The sensor was applied to determine the colchicine content in pharmaceutical tablets the results of which agreed with those obtained by the pharmacopoeia method.Received December 12, 2002; accepted March 25, 2003 Published online July 16, 2003  相似文献   

7.
Summary A new cardenolide glycoside — sinapoylglucoerysimoside — having the structure of strophanthidin 3-0-[0-sinapoyl--D-glucopyranosyl-(14) 0--digitoxopyranoside — has been found in the seeds ofErysimum marshallianum.Kiev Institute for the Further Training of Doctors. Translated from Khimiya Prirodnykh Soedinenii No. 5, pp. 603–606, September–October, 1975.  相似文献   

8.
A novel O—N—N—O-type tetradentate ligand H4mda (H4mda = malamido-N,N-diacetic acid) and the corresponding square-planar copper(II) complexes have been prepared and characterized. The mda4– ligand coordinates to the copper(II) ion via two pairs of deprotonated ligating atoms (two carboxylate oxygens and two deprotonated amide nitrogens) with in-plane square chelation. A four-coordinate, square-planar geometry has been established crystallographically for the [Co(H2O)6][Cu(mda)] · 2H2O complex. Structural data correlating the square-planar geometry of the [Cu(mda)]2– unit are discussed in relation to information obtained for similar complexes. The i.r., electronic, absorption and reflectance spectra of the complexes are analysed in comparison with related complexes of known geometries.  相似文献   

9.
Yuan  Ai-Hua  Lu  Lu-De  Shen  Xiao-Ping  Chen  Li-Zhuang  Yu  Kai-Bei 《Transition Metal Chemistry》2003,28(2):163-167
A cyanide-bridged FeIII–FeII mixed-valence assembly, [FeIII(salen)]2[FeII(CN)5NO] [salen = N,N-ethylenebis(salicylideneiminato)dianion], prepared by slow diffusion of an aqueous solution of Na2[Fe(CN)5NO] · 2H2O and a MeOH solution of [Fe(salen)NO3] in an H tube, has been characterized by X-ray structure analysis, i.r. spectra and magnetic measurements. The product assumes a two-dimensional network structure consisting of pillow-like octanuclear [—FeII—CN—FeIII—NC—]4 units with dimensions: FeII—C = 1.942(7) Å, C—N = 1.139(9) Å, FeIII—N = 2.173(6) Å, FeII—C—N = 178.0(6)°, FeIII—N—C = 163.4(6)°. The FeII—N—O bond angle is linear (180.0°). The variable temperature magnetic susceptibility, measured in the 4.8–300 K range, indicates the presence of a weak intralayer antiferromagnetic interaction and gives an FeIII–FeIII exchange integral of –0.033 cm–1.  相似文献   

10.
A new hydrolyzable tannin substance has been isolated from an anqueous hydrolysate of an aqueous-acetone extract of the fruit ofRosa platyacantha — 1-dehydrotrigalloyl--D-glucose — and it has been named platyacanthin. The substance is a minor component of the tannin complex.S. M. Kirov Kazakh State University, Alma-Ata. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 829–831, November–December, 1985.  相似文献   

11.
Summary From the roots ofAjuga turkestanica (Rg1.) Briq. family Labiatae a new phytoecdysone — turkesterone — has been isolated. It has been shown that it is 1120R-dihydroxyecdysone.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 466–470, July–August, 1975.  相似文献   

12.
Summary A new quercetin diglycoside — campanuloside — has been isolated from the herbage ofCampanula glomerata L., and for it the structure of quercetin 3-O--D-galactopyranoside-7-O--D-glucopyranoside has been proposed.Leningrad Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 134–136, March–April, 1975.  相似文献   

13.
It is shown that in the presence of reducing agents — light alkanes (C3–C4) or carbon monoxide — the temperature for the elimination of nitrogen(I) oxide over iron-containing zeolite catalysts of various structural types (Y, M, pentasil) is reduced by 70–150 °C. In the presence of excess oxygen (SCR process conditions) a greater conversion of N2O(90–94%) is achieved at even lower temperatures (up to 50–150 °C less) with the use of hydrocarbons, and the activity of the catalysts correlates with the presence of strongly acidic B centers on their surfaces.__________Translated from Teoreticheskaya i Éksperimentalnaya Khimiya, Vol. 41, No. 1, pp. 35–39, January–February, 2005.  相似文献   

14.
The catechin and proanthocyanidin compositions of the leaves and bark ofZiziphus jujuba have been studied over the vegetation periods. This has led to the isolation of 16 compounds, including 8 monomeric catechins — (–)-epiafzelechin, (–)-epicatechin, (–)-epigallocatechin, (–)-epicatechin gallate, (–)-epigal-locatechin gallate, (+)-catechin, (+)-catechin gallate, and (+)-gallocatechin; 4 dimeric proanthocyanidins — (–)-epiafzelechin-(4-8)-(–)-epicatechin, proanthocyanidin B-2, (–)-epicatechin-(4-8)-(–)-epigallocatechin, and (–)-epiafzelechin-(4-8)-(–)-epigallocatechin; and 4 oligomeric proanthocyanidins consisting of epiafzelechin, epigallocatechin, catechin, and epicatechin with different degrees of polymerization. Their structures have been established by a study of PMR and13C NMR spectra and the products of chemical transformation.The materials of this paper were presented at the Second International Symposium on the Chemistry of Natural Compounds (SCNC, Eskiehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–231, March–April, 1997.  相似文献   

15.
The chemical composition of a petroleum ether extract of the bark of the Siberian spruce has been studied. Extracts included saturated aliphatic alcohols and C16-C24 acids — abietic, dehydroabietic, isopimaric, oleic, lineolic, and linolenic — alkyl ferulates, ketones, and alcohols of the serratene type, and also 4-stigmasten-3-one. Onoceradienedione and onoceradienediol — precursors of the serratene triterpenoids — and also a saturated vicinal diol — triacontane-10,11-diol — have been isolated from the extractive substances of conifer in the native form for the first time.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 654–662, November–December, 1992.  相似文献   

16.
    
24-Ethylcholesta-7, 22E-diene-3,5,6-triol — a natural trihydroxysteroid from the bryozoanMyriapora truncata — has been synthesized from stigmasterol.Institute of Bioorganic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 664–669, September–October, 1989.  相似文献   

17.
    
cis- and trans-Cheilanthene-3, 19-diols — structurally close analogues of the parent of the cheilanthane sesterterpenoids cheilantha-6,13,19-triol and substances related to it — have been synthesized.Institute of Chemistry, Moldavian SSR Academy of Science, Kishinev. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 353–358, May–June, 1990.  相似文献   

18.
Two cyano-bridged assemblies, [FeIII(salpn)]2[FeII(CN)5NO] (1) and [FeIII (salpn)]2[NiII(CN)4] (2) [salpn = N, N-1,2-propylenebis(salicylideneiminato)dianion], have been prepared and structurally and magnetically characterized. In each complex, [Fe(CN)5NO]2– or [Ni(CN)4]2– coordinates with four [Fe(salpn)]+ cations using four co-planar CN ligands, whereas each [Fe(salpn)]+ links two [Fe(CN)5NO]2– or [Ni(CN)4]2– ions in the trans form, which results in a two-dimensional (2D) network consisting of pillow-like octanuclear [—MII—CN—FeIII—NC—]4 units (M = Fe or Ni). In complex (1), the NO group of [Fe(CN)5NO]2– remains monodentate and the bond angle of FeII—N—O is 180.0°. The variable temperature magnetic susceptibilities, measured in the 5–300 K range, show weak intralayer antiferromagnetic interactions in both complexes with the intramolecular iron(III)iron(III) exchange integrals of –0.017 cm–1 for (1) and –0.020 cm–1 for (2), respectively.  相似文献   

19.
Starting from benzyl 3,4-di-O-acetyl-6-O-trityl-N-acetyl--glucosamine and benzyl -benzyl-4-O-acetyl-N-acetylmuramate, 2-acetamido-2-deoxy-D-glucopyranuronyl-L-alanyl-D-isoglutamine and O-(2-acetamido-2-deoxy-D-glucopyranuronyl-L-alanyl-D-isoglutamin-3-yl)-D-lactoyl-L-alanyl-D-isoglutamine — uronoyldipeptide analogs of N-acetylglucosamine and N-acetylmuramoyl dipeptides — have been synthesized.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 850–855, November–December, 1988.  相似文献   

20.
A known ecdysteroid — -ecdysone- and a new phytoecdysteroid — polypodin B-22-O-benzoate — have been isolated from the seeds ofRhaponticum carthamoides (Willa) Iljin. Alkaline hydrolysis of the latter gave polypodin B. Its structure has been established on the basis of chemical transformations and spectral characteristics.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 40 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 851–853, November–December, 1997.  相似文献   

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