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1.
The reaction of 5(4)-aminoimidazole-4(5)-carboxhydrazide with nitrous acid was investigated. A mixture of four compounds, viz., 5-diazoimidazole-4-carboxazide, 5-diazoimidazole-4-carboxylic acid, 5(4)-aminoimidazole-4(5)-carboxazide, and 2-azahypoxanthine, is formed under all of the investigated conditions, 5(4)-Azidoimidazole-4(5)-carboxamide derivatives were obtained in the reaction of diazoimidazole-carboxazide with various amines in protic and aprotic solvents. 5-N-(Piperidyl)-azoimidazole-4-carboxazide was isolated only in the reaction with piperidine in an aqueous medium.See [1] for Communication 8.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1536–1540, November, 1980.  相似文献   

2.
The acylation of 5(4)-aminoimidazole derivatives was studied. It is shown that acylation by means of carboxylic acid anhydrides and chlorides takes place at the amino group, whereas acylation by means of chlorocarbonic acid esters takes place at the nitrogen atoms of the imidazole ring. Methods for the selective introduction of a carbomethoxy group in the 1, 3, and 5 positions of the 5(4)-aminoimidazole-4(5)-carboxamide molecule were developed.See [1] for communication 13.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 247–252, February, 1984.  相似文献   

3.
The IR, UV, and PMR spectra of 5(4)-mercaptoimidazole-4(5)-carboxamide, 5(4)-hydroxyimldazole-4(5)-thiocarboxyamide, 5(4)-mercaptoimidazole-4(5)-thiocarboxamide, and the corresponding methyl derivatives were studied. It is shown that the mercaptoimidazoles obtained exist in the form of zwitterions in solution. The methylation of the mercapto- and hydroxyimidazoles with various methylating agents in solvents was investigated, and the reaction of the thioamides with hydrazine was carried out.See [1] for Communication 10.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 957–962, July, 1982.  相似文献   

4.
4-Cyano-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)-5-methylimidazole ( 4 ) and its corresponding 5-cyano-4-methyl substituted isomer ( 5 ) have been obtained by ribosylation of 4(5)-cyano-5(4)-methylimidazole ( 3 ) via the mercuric cyanide method or by ribosylation of the trimethylsilyl derivative of 3 . Treatment of 4 with methanolic ammonia, ammonium chloride in liquid ammonia and potassium hydrosulfide provided 4-cyano-1-β-D-ribofuranosyl-5-methylimidazole ( 6 ), 1-β-D-ribofuranosyl-5-methylimidazole-4-carboxamide ( 2 ) and 1-β-D-ribofuranosyl-5-methylimidazole-4-thiocarboxamide ( 11 ) respectively. Reaction of 6 with hydroxylamine afforded the corresponding 4-carboxamidoxime substituted nucleoside ( 13 ) which on catalytic reduction in the presence of ammonium chloride, was transformed into 1-β-D-ribofuranosyl-5-methylimidazole-4-carboxamidine ( 14 ) as hydrochloride salt.  相似文献   

5.
The chemical transformations of 6-[(1-methyl-4-nitro-5-imidazolyl)thio]purine (azathiopurine) —hydrogenation, acetylation, alkylation by lower alkyl halides at positions 7 and 9 of the purine ring, hydrolytic cleavage at the C(6)–S and S–C(5) bonds— were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 372–379, March, 2000.  相似文献   

6.
2-Acetamide-4-methyl-5-(5-R-2-furyl)thiazoles were obtained by the reaction of 2-(5-R-furfuryl)thiuronium salts with acetic anhydride. The reaction intermediates — 2-(5-R-furfuryl)-1,3-diacetylthioureas — were isolated and characterized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 557–562, April, 1990.  相似文献   

7.
Poly(2-methyl-5-vinylpyridine) is sulfurized with elemental sulfur at 140—320 °C to release hydrogen sulfide and to give black lustrous powders (sulfur content up to 45%) possessing electric conductivity (6.4·10–11—1.6·10–7 S cm–1), paramagnetism (spin concentration 6.2·1018—5.0·1019 sp g–1, g = 2.0043—2.0046, H = 0.49—0.58 mT), and redox and complex-forming properties. Elemental analysis data, IR, ESR, and mass spectra, DSC and TGA data, electric conductivity, electrochemical activity and chemical properties (salt formation and complexation) of the materials synthesized correspond to cross-liked poly(6-methyl-5-sulfanylthieno[2,3-b]pyridine-4-thione), poly(thieno[2,3-b]azepine-4,5(6H)-dithione), and related structures.  相似文献   

8.
Some 4-N-thioureido- and -ureido derivatives are synthesized by reacting 1-phenyl-3-methyl-4-aminopyrazolone(5) hydrochloride at 40–50°, in alcohol solution, with potassium thiocyanate in the presence of sodium acetate plus carbon disulfide, phenylisothiocyanate, and hexamethylenediisocyanate. Acetylation of 1-phenyl-3-methyl-4-aminopyrazolone(5) with C1–C8 aliphatic carboxylic acids takes place under more drastic conditions at 100–150°, to give the corresponding 1-phenyl-3-methyl-4-acylaminopyrazolones(5), isolated in 40–60% yield. The UV spectra of the compounds studied are investigated.For Part I, see [1].  相似文献   

9.
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   

10.
In order to obtain 5(4)-aminoimidazole-4(5)carboxamide antagonists, the.hydrazides of 5(4)-aminoimidazole-4(5)-carboxylic acid and 5(4)-aminoimidazole-4(5)hydroxamic acid were synthesized, and the reaction of 5(4)-bromo-4(5)sulfamoylimidazole with amines was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1421–1422, October, 1971.  相似文献   

11.
Successive treatment of N-[(1-ethoxy)alken-2-yl]benzotriazoles VII with butyllithium and trimethylsilyl chloride in TH-Fat — 78°C followed by refluxing in acidic acetone generated ring-opened 1-(2-aminophenyl)-5-ethoxy-4-methyl-3 phenylpyrazole VIII and 4-methyl-3 phenylpyrazolo[5, 1-b]benzimidazole IX.Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 775–780, June, 1996. Original article submitted May 14, 1996.  相似文献   

12.
5-Diazoimidazole-4-carboxazide was isolated in the diazotization of 5(4)-aminoimidazole-4(5)-carboxhydrazide. The diazotization of N-substituted hydrazides of 5(4)-aminoimidazole-4(5)-carboxylic acis was studied. It is shown that the resulting diazo derivatives undergo cyclization to 3-arylideneaminoimidazo[4,5-d]-1,2,3-triazin-4-ones.See [1] for communication 7.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 984–985, July, 1979.  相似文献   

13.
The crystal and molecular structures of the 3′,5′-di-O-acetyl-N(4)-hydroxy-2′-deoxycytidine molecule and its 5-fluoro congener have been determined by X-ray single crystal diffraction. The 3′,5′-di-O-acetyl-N(4)-hydroxy-5-fluoro-2′-deoxycytidine molecule crystallizes in the space group C2 with the following unit cell parameters: a = 21.72 Å, b = 8.72 Å, c = 8.61 Å, and β = 90.42. 3′,5′-di-O-acetyl-N(4)-hydroxy-2′-deoxycytidine also belongs to the monoclinic space group C2 and the unit cell parameters are: a = 39.54 Å, b = 8.72 Å, c = 22.89 Å, and β = 95.26. The non-fluorine analogue demonstrates a rare example of crystal structure with five symmetry-independent molecules in the unit cell. All the molecules in both crystal structures have the sugar residue anti oriented with respect to the base, as well as have the N(4)-OH residue in cis conformation relatively to the N(3)-nitrogen atom. In addition to the molecular geometries from X-ray experiment, the optimized molecular geometries have been obtained with the use of theoretical ab initio calculations at the RHF/6-31G(d) level. The corresponding geometric parameters in the molecules of 3′,5′-di-O-acetyl-N(4)-hydroxy-2′-deoxycytidine and its 5-fluoro congener have been compared. The differences including the C(5)=C(6) bond shortening and C(4)—C(5)—C(6) angle widening in the fluorine analogue are discussed in this paper in relation to the molecular mechanism of enzyme, thymidylate synthase, inhibition by N(4)-hydroxy-2′-deoxycytidine monophosphate and its 5-fluoro congener.  相似文献   

14.
4(5)-Sulfonyl chlorides, which were converted to the corresponding sulfamoyl derivatives, were obtained from the amide and ethyl ester of 4(5)-mercaptoimidazole-5(4)-carboxylic acid by oxidative chlorination. The azide of 4(5)-sulfamoylimidazole-5(4)carboxylic acid was synthesized through 4(5)-sulfamoylimidazole-5(4)-carboxylhydrazide, and its conversion in various media to 5(4)-aminoimidazole-4(5)-sulfonamide derivatives and to 3,4-dihydro-3-oxoimidazo[4,5-e]-1,2,4-thiadiazine 1,1-dioxide was studied.See [1] for communication V.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1119–1122, August, 1976.  相似文献   

15.
The corresponding 5(4)-mercaptoimidazoles, from which various 5(4)-mercaptoimidazole-4(5)-carboxylic acid derivatives were synthesized, were obtained from the amide and ethyl ester of 5-diazoimidazole-4-carboxylic acid by substitution of the diazo group. 5-Diazo-imidazole-4-hydroxamic acid does not undergo substitution with sodium disulfide but does undergo cyclization to 3-N-hydroxyimidazo[4,5-d]-1,2,3-triazin-4-one under these conditions. The kinetics of the cyclization of diazoimidazoles were studied, and the interrelationship between the structure and reactivity of the latter was examined.See [1] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1550–1554, November, 1975.  相似文献   

16.
5-Aroyl-4-furyl-2-(morpholin-4-yl)thiazoles were synthesized by the reaction of (morpholin-4-ylthiocarbonyl)furan-2-carboxamide with α-bromoketones.  相似文献   

17.
The tautomerism of 1-phenyl-3-methyl-4-benzyl-5-pyrazolone —a side product in the reaction of acetoacetic ester with benzaldehyde phenylhydrazone — was studied by IR and PMR spectroscopy, and its thermodynamic characteristics were determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 355–359, March, 1991.  相似文献   

18.
Imidazole ring coordination compounds are very useful models to better understand the coordination properties and the reaction mechanisms of biologically important systems. On the basis of previous work, new Co(II)-, Ni(II)- and Cu(II)-4(5)-aminoimidazole-5(4)-carboxamide coordination compounds have been synthesized and characterized by elemental analysis, UV-Vis and IR spectroscopies. Their thermal stability was determined by differential scanning calorimetry and by thermogravimetry, and the decomposition mechanisms were investigated by evolved gas analysis (EGA).  相似文献   

19.
New condensed systems — (5,4-thiazolo)imidazoline-2-thione and pyrazolo[5,4-d]thiazoles -are formed by reaction of phosphorus pentasulfide with 5-acetamidothiohydantoins and 4-bromo-5-acetamido derivatives of pyrazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 932–934, July, 1974.  相似文献   

20.
A series of novel 5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives(6a–6n, 7a, 7b, and 8a-8f)were synthesised by placing the amide bond at the 4-position of the pyrazole ring. These derivatives differed from the structure of chlorantraniliprole analogues with the amide bond at the 5-position of the pyrazole ring. Preliminary bioassay results revealed that a few title compounds exhibited good insecticidal activities against lepidopteran pests, such as Plutella xylostella, Mythimna separate, Heliothis armigera, and Ostrinia nubilalis. Some title compounds also elicited broad-spectrum insecticidal activities against dipterous insects including Culex pipiens pallens after altering the amide position. Similar to pyrazole-5-carboxamide analogues, compounds 6b and 6e showed 100% insecticidal activity against P. xylostella, C. pipiens pallens, and M. separate at concentrations of 200, 2, and 200 mg/m L, respectively.This finding suggested that 5-(trifluoromethyl)-1H-pyrazole-4-carboxamide derivatives are potential alternative insecticides for management of agriculture pests.  相似文献   

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