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Y. H. R. Jois C. D. Kwong J. M. Riordan J. A. Montgomery J. A. Secrist 《Journal of heterocyclic chemistry》1993,30(5):1289-1292
Ribosylation of 3-amino-5H-[1,2,4]triazolo[4,3-b][1,2,4]triazole ( 1 ) with l-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose and stannic chloride resulted in the following protected nucleoside analogs: 3-amino-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)[1,2,4]triazolo[4,3-β][1,2,4]triazole ( 4 ), 3-amino-1-(2,3,5-tri-O-benzoyl-α-D-ribofuranosyl)[1,2,4]triazolo[4,3-β][1,2,4]triazole ( 5 ), 3-amino-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)[1,2,4]triazolo[4,3-β][1,2,4]triazole ( 5 ), and 3-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl) amino-5H-[1,2,4]triazolo[4,3-b]-[1,2,4]triazole ( 7 ). Compounds 4–6 were deprotected to 3-amino-1-β-D-ribofuranosyl[1,2,4]triazolo[4,3-b][1,2,4]-triazole ( 3 ), 3-amino-1-α-D-ribofuranosyl[1,2,4]triazolo[4,5-b][1,2,4]triazole ( 8 ), and 3-imino-2H-2-β-D-ribo-furanosyl[1,2,4]triazolo[4,3-b][1,2,4]triazole ( 9 ), while 7 could not be deprotected without decomposition. Compounds 1, 4, 6, 7 , and 9 were screened and found to have no antiviral activity. 相似文献
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The syntheses of some diheterocyclic compounds from 2-thioacetohydrazide- 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (1) are described. Compound 1 can be converted into triazoles, 1,3,4-oxadiazoles, and 1,3,4-thiadiazoles. The structures of the intermediates and the target compounds were confirmed by (1)H-NMR, MS and elemental analyses. 相似文献
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A. V. Komkov A. S. Shashkov S. V. Baranin V. A. Dorokhov 《Russian Chemical Bulletin》2013,62(5):1248-1254
A new representative of heterocyclic hydrazines, viz., 6-hydrazino-3,4-dimethyl-1H-pyrazolo[3,4-d]pyrimidine (3) was synthesized from diacetyl ketene N,S-acetal. A condensation of hydrazine 3 with amide acetals or aldehydes and subsequent cyclization furnished pyrazolo[4,3-e][1,2,4]triazolo[4,3-a]pyrimidines, whose structure was confirmed by 1H, 13C, and 1H/15N HMBC NMR spectroscopy. Reactions of hydrazine 3 with acetylacetone, ethyl acetoacetate, diethyl malonate, and acetic anhydride were studied. 相似文献
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《Polyhedron》1986,5(9):1405-1411
Copper(II) coordination compounds of several CuA2 salts (A = PF6, BF4, ClO4, CF3SO3 or NO3) with 5,7-dimethyl[1,2,4]triazolo[1,5-a]pyrimidine (dmtp) as a ligand have been studied. The crystal structure of [Cu(dmtp)4(H2O)2](PF6)2 is described. This compound is monoclinic, space group P21/c, a = 11.826(2) Å, b = 9.463(2) Å, c = 17.673(3) Å, β = 97.50(1)°, Z = 2, dcalc. = 1.66 Mg m−3, and has been refined to a final discrepancy factor (R) of 0.0382 based on 2316 reflections. The structure consists of PF−6 anions and centrosymmetric mononuclear [Cu(dmtp)4(H2O)2]2+ cations, Cu2+ being coordinated by four equatorial N(3)-bonded dmtp molecules with CuN = 2.019 and 2.050 Å, and by two axial water molecules with CuO = 2.650 Å. The water molecules form intramolecular hydrogen bonds with the dmtp N(4) atoms. 相似文献
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L. Kosychova Z. Stumbreviciute L. Pleckaitiene R. Janciene B. D. Puodziunaite 《Chemistry of Heterocyclic Compounds》2004,40(6):811-815
A one-pot synthetic approach to the novel 5,6-dihydro-4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepines by thermal cyclization of 4-acylhydrazino-2,3-dihydro-1H-1,5-benzodiazepines is described. 相似文献
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Kamal F. Atta Abdel Moneim El-Massry Hamida Abdel Hamid El Sayed H. El Ashry Adel Amer 《Journal of heterocyclic chemistry》1994,31(2):549-552
The transformation of 2-chloro-3-[5-(acetoxymethyl)-1-phenylpyrazol-3-yl]quinoxaline 3 to 1-aryl-4-[5-(hydroxymethyl-1-phenylpyrazol-3-yl][1,2,4]triazolo[4,3-a]quinoxalines 4a-c has been achieved upon treatment with aroylhydrazines in boiling butanol. Compounds 4a-c were smoothly acetylated by acetic anhydride to give their acetyl derivatives 5a-c in good yield. 4-[5-(Acetoxymethyl)-1-phenylpyrazol-3-yl]-1-methyl[1,2,4]triazolo[4,3-a]quinoxaline was prepared by ring closure of 2-hydrazino-3-[5-(hydroxymethyl)-1-phenylpyrazol-3-yl]quinoxaline 6 by the action of acetic anhydride. The reaction of 6 with acetylacetone afforded 3-[5-(hydroxymethyl)-1-phenylpyrazol-3-yl]-2-(3,5-dimethylpyrazol-1-yl)quinoxaline 8 . In addition, the reaction of 3 with sodium azide in boiling N, N-dimethylformamide yielded the fused tetrazolo[1,5-a]quinoxaline 9 . 相似文献
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The crystal structure of the title compound has been determined by single crystal X-ray diffraction analysis. C15H14N4O3, Mr=298.30, monoclinic, space group P21/n, a=9.483(9),b=11.078(9), c=13.700(9),β=100.19(7)°, V=1417(4)3, Z=4, Dx=1.399 g.cm-3, μ=0.0942 mm-1; F(000)=624, final R=0.074 and Rw=0.074 for 1502 observed reflections[I≥3σ(I)]. The results show that all ring atoms in the triazolopyrimidinyl moiety were coplanar with strong tensile force, which might be an important active site. 相似文献
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P. Kumar 《Chemistry of Heterocyclic Compounds》2012,47(10):1237-1243
A simple, solvent-free and effective method for oxidative cyclization of 2-pyridyl- and 2-quinolyl-hydrazones with phenyliodine
bis(trifluoroacetate) and iodobenzene diacetate to the corresponding 3-aryl[1,2,4]triazolo[4,3-a]pyridines and 1-aryl[1,2,4]triazolo[4,3-a]quinolines is described. All reactions were characterized by short reaction times and high yields at room temperature. All
reactions were carried out by just grinding the reaction components. 相似文献
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T. Sudhakar Rao Ganapathi R. Revankar Ravi S. Vinayak Roland K. Robins 《Journal of heterocyclic chemistry》1992,29(2):343-354
The synthesis of the congeners of uridine and cytidine in the pyrazolo[4,3-d]pyrimidine and pyrrolo[3,2-d]-pyrimidine ring system is described. Glycosylation of the trimethylsilyl (TMS) derivative of pyrazolo[4,3-d)pyrimidine-5,7(1H,4H,6H)-dione (4) with either 1-bromo- or 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose 5 and 6 , respectively in the presence of a Lewis acid catalyst gave the protected nucleoside 7 , which on debenzoylation afforded the uridine analogue 4-β-D-ribofuranosylpyrazolo[4,3-d]pyrimidine-5,7(1H,6H)-dione (8). Thiation of 7 gave 13 , which on deprotection yielded 4-β-D-ribofuranosyl-5-oxopyrazolo[4,3-d]pyrimidine-7(1H,-6H)-thione (14). Ammonolysis of 13 gave a low yield of the cytidine analogue 15. A chlorination of 7 , followed by amination furnished an alternative route to 15. A similar glycosylation of TMS-4 with 2,3,5-tri-O-benzyl-α-D-arabinofuranosyl chloride (16) gave mainly the N4 glycosylated product 17 , which on debenzylation furnished 4-β-D-arabinofuranosylpyrazolo[4,3-d]pyrimidine-5,7(1H,6H)-dione (18). 7-Amino-4-β-D-arabinofuranosylpyrazolo[4,3-d]pyrimidin-5(1H)-one (23) was prepared from 17 via the pyridinium chloride intermediate 21. Condensation of the TMS derivative of pyrrolo[3,2-d]pyrimidine-2,4(1H,3H,5H)-dione (24) with 6 , followed by deprotection of the reaction product gave 1-β-D-ribofuranosylpyrrolo[3,2-d]pyrimidine-2,4(3H,5H)-dione (26). Similarly, TMS-24 was reacted with 16 to give a mixture of the blocked nucleosides 31 and 32 , which on debenzylation afforded a mixture of two isomeric compounds 34 and 35. 1-β-D-Arabinofuranosylpyrrolo[3,2-d]pyrimidine-2,4(3H,5H)-dione (34) was converted to the ara-C analogue 38 via the 3-nitrotriazolyl intermediate 36. The structure of 38 was confirmed by single crystal X-ray diffraction studies. 相似文献
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Fathy M. Abdelrazek Sobhi M. Gomha Hassan M. Abdel-aziz Mohamed S. Farghaly Peter Metz Ahmed Abdel-Shafy 《Journal of heterocyclic chemistry》2020,57(4):1759-1769
A novel series of 1,5-dihydropyrido-triazolo-pyrimidine derivatives were prepared by cyclocondensation of 2-thioxo-pyrido[2,3-d]pyrimidines (prepared from reaction of chalcone with 6-aminothiouracil) with a variety of hydrazonoyl chlorides. Based on spectroscopic evidence and their chemical syntheses, the structures of the newly prepared compounds were elucidated. Designated compounds are forced for molecular docking by using MOE 2014.010 Package software; one of in silico study tools. Synthesized compounds are targeting Human Cyclin-defendant Kinase 2 (CK2) PDB ID (1PXO.Protein data bank) due to its important role in controlling the human cell cycle and also for meiosis. 相似文献
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Feng-Yu Piao Cheng-Xi Wei Rong-Bi Han Wen-Bin Zhang Wei Zhang Ri-Shan Jiang 《合成通讯》2013,43(16):2337-2345
A series of novel 9-alkoxy-6,7-dihydro-2H-benzo[c][1,2,4]triazolo[4,3-a]azepin-3(5H)-one derivatives was designed and synthesized starting from 2,3,4,5-tetrahydro-7-hydroxy-1H-2-benzazepin-1-one. The structures of these compounds were confirmed by mass, 1H NMR infrared spectra, and elemental analysis. Their anticonvulsant activity was evaluated by maximal electroshock (MES) test, and their neurotoxic effects were determined by the rotarod neurotoxicity test. The results shown that 3k was the most active compound with median effective dose (ED50) of 27.3 mg/kg, median toxicity dose (TD50) of 118.3 mg/kg, and protective index (PI) of 4.3. Possible structure–activity relationship is discussed. 相似文献
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Lashmanova Eugenia A. Agarkov Artem S. Rybakov Victor B. Shiryaev Andrey K. 《Chemistry of Heterocyclic Compounds》2019,55(12):1217-1221
Chemistry of Heterocyclic Compounds - Triazolo[4,3-a]pyrimidines were prepared by the reduction of 5,6,7-trisubstituted 2-(arylhydrazinylidene)-5H-[1,3]thiazolo[3,2-a]- pyrimidin-3(2H)-ones with... 相似文献
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I. Krężel 《Chemistry of Heterocyclic Compounds》1987,23(11):1233-1235
In the reaction of 1-ethoxycarbonyl-2-methylthio-1,4,5,6-tetrahydropyrimidine with thiosemicarbazide, 2-aminothiocarbonyl-3-oxo-2,3,5,6,7,8-hexahydro-sym-triazolo[4,3-a]pyrimidine is formed, which as a result of the successive action of methyl iodide, K2CO3 solution, and cyclic amines, converts into 2,3,5,6,7,8-hexahydro-8-oxo-sym-triazolo[4,3-a]pyrimidine.For Communication 3, see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1540–1542, November, 1987. 相似文献