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1.
Summary A new synthetic analog of oxytocin — [4-histidine] oxytocin — has been obtained and its uterotonic activity has been determined.Leningrad State University. Translated from Khimiya Prirodnykh Khimii, No. 4, pp. 498–502, July–August, 1975.  相似文献   

2.
Summary The interconversions of the alkaloids of Sophora alopecuroides L. have been studied by feeding the plants with tritium-labelled alkaloids ([3H]sophoridine, [3H]pachycarpine, [3H]cytisine, [3H]isosophoridine, [3H]allomatrine, and [3H]N-methylcytisine). It has been established that the conformationally stable isomers of the alkaloids — isosophoridine and allomatrine — do not take part actively in the metabolism of the alkaloids. It has also been shown that the alkaloids of the sparteine group are converted into martrine alkaloids in the development of the plant. The methylation of cytisine to N-methylcytisine and the reverse transition have been shown experimentally in the plant organism.V. I. Lenin Tashkent State University. Institute of Plant Biochemistry, Academy of Sciences of the GDR, Halle. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 244–247, March–April, 1977.  相似文献   

3.
A new heterocyclic base — 2-methylthieno[3,2-b]thieno[2,3-d]thiazole — was synthesized by heating 2-acetamido-3-hydroxythieno[3,2-b]thiophene with phosphorus pentasulfide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1039–1041, August, 1976.  相似文献   

4.
    
The synthesis has been effected in an aqueous medium of oligonucleotide phosphorazolidates derived from imidazole, 2-methylimidazole, benzimidazole, pyrazole, triazole, and benzotriazole with yields close to quantitative. It has been shown that they are all phosphorylating agents in an aqueous medium and can be used as reagents for the directed complementary template assembly of nucleic acid duplexes (chemical ligation). The most reactive are the imidazole, 2-methylimidazole, and benzotriazole derivatives.Abbreviations adopted in this paper: MCC — microcolumn chromatography; OU260 — amount of nucleotide material in optical units determined at a wavelength =260 nm; CDI - 1-(3-methylaminopropyl)-3-ethylcarbodiimide; PEG — polyethyleneglycol; PAAG — polyacrylamide gel; MES — 2-morpholinoethanesulfonic acid; HEPS — 2-[4-(2-hydroxyethyl)piperazine-1-yl]ethanesulfonic acid.Chemical Faculty and A. N. Belozerskii Interfaculty Problem Scientific-Research Laboratory of Molecular Biology and Bioorganic Chemistry of Moscow State University. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 723–731, September–October, 1987.  相似文献   

5.
The directed synthesis of structurally isomeric nitronaphthaloperinones — 10-nitro-and 11-nitro-14H-benz[4,5]isoquinolino[2,1-a]perinidin-14-ones — has been effected.For Communication I, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 842–843, June, 1970.  相似文献   

6.
A study has been made of the fruit lipids of four vitamin-bearing varieties of rose: Vorontsovskii-1, Vorontsovskii-3, Besshipnyi, and Vitaminnyi of VNIIVI [All-Union Scientific-Research Institute of the Vitamin Industry], that have been introduced into Tashkent Botanical Garden. It has been found that the oil is concentrated mainly in the seeds — about 9% — and the carotenoids in the pericarp — 2613–3933 mg% of the weight of the lipids. Essential fatty acids make up 61.5–70.6% of the weight of the fruit fatty acids.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 674–675, September–October, 1995. Original article submitted April 22, 1995.  相似文献   

7.
The dissociation and the structure at the isomeric [M — HCN]+ and [M — 2HCN]+ ions, formed during the fragmentation of naphthiridines and benzazines, were investigated by the collisionally activated dissociation (CAD) method. It was established that the stable [M — HCN]+ ions of 1,5- and 1,8-naphthiridines, 1,6-naphthiridine, quinoxaline, and quinazoline have different structures. The [M — 2HCN]+ ions can exist in two isomeric forms, one of which is characteristic of naphthiridines and the other of benzazines.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vo. 25, No. 5, pp. 626–629, September–October, 1989.  相似文献   

8.
Summary The first-order polarized basis sets for the use in high-level-correlated investigations of molecular electric properties have been generated for Pb, Bi, Po, and At. The performance of the standard [10.17.14.5/13.11.8.2] and extended [20.17.14.9/13.11.8.4] basis sets has been examined in nonrelativistic and quasirelativistic calculations for atoms and simple closed-shell hydrides. The relativistic contributions to electric dipole properties of those systems have been evaluated by using the recently developed quasirelativistic scheme. The predicted dipole polarizability of At is in good agreement with the results of other relativistic calculations. The calculated quasirelativistic dipole moments of BiH3 (–0.499 a.u.), PoH2 (–0.207 a.u.), and AtH (+0.036 a.u.) involve a significant relativistic contribution which amounts to —0.230 a.u., –0.177 a.u., and –0.097 a.u., respectively. The basis set details append this paper. They are also available as a part of the basis set library of the MOLCAS system.  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.
    
The proof of the structures of two isomeric alkaloids — nitramine and isonitramine — from two species of plants of the genusNitraria is given. Their diastereoisomerism with respect to the C7 asymmetric atom has been established. This is the first time that alkaloids with the structure of 2-azaspiro[5,5]undecan-7-ol have been found.Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 623–629, September–October, 1981.  相似文献   

11.
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   

12.
The reactions of organomagnesium derivatives of 2-methyl- or 2,3-dimethyl-7-azaindoles and 2,3-dimethylbenz[4,5]- or -[6,7]indoles with diethyl oxalate, and the reactivity of the resulting ethoxalylindoles towards phenylmagnesium bromide, have been examined. It has been shown that the course of the reaction is dependent on the solvent and the structures of the starting materials.No footnote given in Russian original — Publisher.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1206–1209, September, 1987.  相似文献   

13.
Summary 1. Qualitative and quantitative compositions of the main alkaloids in five development phases of theGoebelia pachycarpa C. A. Mey. have been determined.2. The radioactivities of the alkaloids isolated after feeding the plant with assumed precursors -[2-14C] lysine and [1,5-14C] cadaverine — show that vigorous synthesis of alkaloids takes place in the flowering and budding periods.3. The results of an investigation of the oxidation products and of the alkaloids introduced and isolated after the feeding of plants with labelled matrine and labelled sophocarpine show that the alkaloids undergo interconversion without intramolecular changes.V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh, Soedinenii, No. 4, pp. 549–552, July–August, 1977.  相似文献   

14.
3-Benzoyl-3a,4,6,6a-tetrahydrothieno[3,4-d][1,2,3]oxathiazoline 2-oxide is formed as a result of intramolecular cyclization of cis-4-benzamido-3-chlorosulfitothiophan. Only one sulfur atom — that of the sulfoxide group — is removed from the cyclization product and the analogous 3-methoxycarbonyl-3a,4,6,6a-tetrahydrothieno[3,4-d][1,2,3]oxathiazoline 2-oxide by the action of Raney nickel; the products in this case are, respectively, cis-4-benzamido-3-hydroxythiophan and 3a,4,6,6a-tetrahydrothieno]3,4-d]oxazolidone. The three-dimensional structure of 3-acyl-3a,4,4,6a-tetrahydrothieno[3,4-d][1,2,3]oxathiazoline 2-oxide was determined by 1H and 13C NMR spectroscopy. A difference between the conformational state of 3-substituted 3a,4,6,6a-tetrahydrothieno[3,4-d][1,2,3]oxathiazoline 2-oxides and 3-substituted 3a,4,6,6a-tetrahydrothieno[3,4-d]oxazolidones was established.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 191–197, February, 1977.  相似文献   

15.
The reaction of 3-[N-(2-naphthyl)formimidoyl]pyridine with substituted acetophenones in the presence of a proton catalyst leads to 1-aryl-3-(3-pyridyl)benzo[f]quinolines. Noncyclic amino ketones — [1-aryl-3-(3-pyridyl)-3-(2-naphthylamino)]-1-propanones — precede the formation of the cyclic products. The IR, UV, PMR, and mass spectra of the synthesized compounds are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 351–354, March, 1989.  相似文献   

16.
A mass-spectrometric study of 2- and 4-azafluorenones and their mono- and polymethyl derivatives showed that the presence of a methyl group in the benzene ring leads to a sharp increase in the relative intensity of the [M — H]+ ion peak. In contrast to the fragmentation of 2- and 4-azafluorenes, the mass spectra of monomethyl-substituted compounds do not contain an [M — CH3]+ fragment; this is probably associated with expansion of the pyridine or benzene ring to a seven-membered ring in the step involving the formation of the molecular ion due to inclusion of the methyl group. The intensity of the [M — CO]+ ion peak in the mass spectra of the 4-azafluorenones is higher by a factor of two with respect to the 2-azafluorenone isomers, and the [M — HCN]+ and [M — H, -HCN]+ ion peaks observed in the mass spectra of 2-azafluorenones are absent in them.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 89–95, January, 1979.  相似文献   

17.
The compositions and the amounts of various groups of liposoluble compounds in the component elements of the fruits ofCitrus unshiu Marc. [satsuna variety of mandarin orange] — the flavedo, the albedo, the membrane, and the flesh — have been determined by chromatographic and chemical methods. About 30 groups of lipid compounds belonging to the classes of neutral lipids and glyco- and phospholipids have been identified and characterized. The fatty-acid compositions of the main classes of lipids have been studied. About 30 different carotenoids have been determined in the various elements of the satsuma orange.M. V. Lomonosov Odessa Technological Institute of the Food Industry. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 342–348, May–June, 1989.  相似文献   

18.
Dioxomolybdenum(VI) complexes [MoO2(L)H2O] and oxomolybdenum(V) complexes [Mo2O3(LH)2Cl2] (where LH2=hydrazones derived from 6–methyl-4–hydroxy-2–hydrazinopyrimidine with salicylaldehyde, 5–methyl-, 5–chloro-, 5–bromo-, 3–methoxy-salilcylaldehyde, or 2–hydroxy-1–naphthaldehyde) have been prepared and characterised by spectroscopic and physico-chemical methods. The MoVI complexes are diamagnetic octahedral structures, whilst the MoV complexes are paramagnetic and probably dimeric, via oxobridging.  相似文献   

19.
This article provides a bibliographic listing of published journal papers concerned with adsorptive separations during 1992–1993. The references are taken from the 40 most important chemical engineering journals. This paper provides an update to the literature as provided in previous bibliographic papers [1, 2]. These previous papers also included membrane-type separations, however due to the number of papers and the diversity of membrane and associated processes, this material is to be published separately [3].Other bibliographic papers covering the more traditional unit operations, e.g. distillation [4], and equilibrium-staged separations in general [5, 6] have been published. Liquid-liquid extraction [7] is the subject of a separate bibliography (for 1992–1993), due to the number of publications on this topic. A bibliography detailing supercritical extraction from 1980–1993 is also to be published separately due to the current interest in this relatively new technology [8]. A complete bibliography of the chemical engineering journal literature from 1967–1993 has been published by the author [9–12]. An earlier bibliography [13] provides access to the literature prior to 1967.  相似文献   

20.
Complexes of composition [VCl(acac)2(OAr1–4)] and [V(acac)2(OAr1–4)2] (HOAr1=HOC6H4NO2–4, HOAr2= HOC6H4OMe-4, HOAr3=HOC6H4But-4 and HOAr4= HOC6H2But-2,6–Me-4; acac=2,4–pentanedionato ion) have been synthesized by the reaction of [VCl2(acac)2] with the respective phenols or their trimethylsilyl derivatives. The complexes have been characterized by physicochemical and spectroscopic techniques. They are non-electrolytes in nitrobenzene. Room temperature magnetic moments in the 1.71–1.82B range are consistent with the VIV system. The reactions of [VCl(acac)2(OAr2)] and [VCl(acac)2(OAr3)] with chloride acceptors have been studied by conductance techniques and the formation of ionic complexes of the types [V(acac)2(OAr2,3)][MCl4] (M=Fe, Al or Sb) and [V(acac)2(OAr2,3)][MCl6] (M=P or Sb) is indicated by the conductance composition curves. Several of these complexes have been isolated and characterized.  相似文献   

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