• Archives of Pharmacal Research
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• v.10 no.1
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• pp.14-17
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• 1987

Several new imidazo [1, 2-b] pyrazole, pyrazolo [5, 1-c]-1, 2, 4-triazine and pyrazolo [5, 1-c] triazole derivatives were prepared from the reaction of 3-antipyrinyl-5-aminopyrazole or its diazonium salt with .alpha.-chloroacetyl derivatives.

• Journal of the Korean Chemical Society
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• v.57 no.5
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• pp.612-617
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• 2013

The versatile, hitherto unreported 3-(4-(2-phenyldiazenyl)-2-oxo-2H-chromen-3-yl)-3-oxopropanenitrile 3 was prepared by two convenient routes: either by the reaction of ethyl 4-(2-phenyldiazenyl)-2-oxo-2H-chromen-3-carboxylate 2 with acetonitrile in the presence of sodium hydride or by treatment of 4-(2-phenyldiazenyl)-3-(2-bromoacetyl)-2H-chromen-2- one 5 with potassium cyanide. Reaction of 3 with heterocyclic diazonium salts 6, 7, 14 and 17 furnished the corresponding hydrazones 8, 9, 15 and 18. The latter hydrazones underwent intramolecular cyclization into the corresponding pyrazolo[5,1- c]-1,2,4-triazine 10, 1,2,4-triazolo[5,1-c]-1,2,4-triazine 11, 1,2,4-triazino[4,3-b]indazole 16 and imidazo[2,1-c]-1,2,4-triazine 19 derivatives, respectively upon refluxing in pyridine.

• Archives of Pharmacal Research
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• v.10 no.3
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• pp.173-178
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• 1987

Several new pyrazolo [1, 5-a]-S-triazine, pyrazolo [4, 5, -elpyrimidine, pyrazolo [1, 5-a] pyrimidine derivatives were synthesized via condensation of 3-antipyrinyl-5-amino-pyrazole (2) with $\beta$$-bifunctional reagents. The azo analogues of pyrazolo [1, 5-a] pyrimidines ; i. e. pyrazolo [5, 1, c]-as-triazine and pyrazolo[5, 1, -c]-as-benzotriazine were synthesized by coupling of diazotized 2-with agents containing active hydrogen.

• Journal of the Korean Chemical Society
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• v.55 no.5
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• pp.781-786
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• 2011

An easy and efficient route for the synthesis of some imidazo[1,2-c]pyrazolo[4,3-e]pyrimidines 3-6, imidazo[1,2-c]pyrazolo[4,3-e]triazine 8, pyrazolo[4,3-e]triazolo[1,5-c]pyrimidines 12-15 and pyrazolo-[3',4':4,5]pyrimido[1,6-b]triazines 16, 17 was described through the reaction of readily available 5-aminopyrazole-4-carbonitrile 1 with different reagents. The in vitro antimicrobial activity of some synthesized compounds was examined. Most of the tested compounds proved to be active as antibacterial and antifungal agents.

• Bulletin of the Korean Chemical Society
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• v.33 no.9
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• pp.2985-2990
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• 2012

New thiazoline derivatives 7a-c, and thiophenes 9a-c linked to indole moiety were easily prepared via the reaction of the acrylamide derivative 3 with phenacyl bromides 4a-c, depending on the reaction conditions. In addition, the reaction of compound 3 with hydrazonoyl chlorides 11a-f afforded a series of 1,3,4-thiadiazole derivatives 13a-f. Moreover, coupling of 3-(3-methyl-1H-indol-2-yl)-3-oxopropanenitrile (2) with the diazonium salts of 3-phenyl-5-aminopyrazole 16 or 3-amino-1,2,4-triazole 17 gave the corresponding hydrazones 18 and 19, respectively. Cyclization of the latter hydrazones yielded the corresponding pyrazolo[5,1-c]-1,2,4-triazine and 1,2,4-triazolo[5,1-c]-1,2,4-triazine derivatives 20 and 21, respectively. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, $^1H$ NMR and mass spectral data. All the synthesized compounds were tested for in vitro activities against certain strains of fungi such as Aspergillus niger, Aspergillus nodulans, Alternaria alternate. Compounds showed marked inhibition of fungal growth nearly equal to the standards.

• Archives of Pharmacal Research
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• v.20 no.6
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• pp.620-628
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• 1997

6-Aryl-5-cyano-4-pyrimidinon-2-thione derivatives 1a-c reacted with ethyl iodide to give the corresponded 2-S-ethylpyrimidin-4-one-derivatives 2a-c. Compounds 2a-c was, in turn, reacted with hydrazine hydrate to give the sulfur free reaction products, 3a-c. These reaction products were taken as the starting materials for the synthesis of several newly synthesized heterocyclic derivatives. Reactions with several halogenated ketones, esters, chloroacetic acid and chloroacetamide give pyrimidotriazines 8,12 and 15 while their reactions with formic acid, acetic acid and carbon disulfide gave the corresponded triazolopyrimidines 17 and 21. The reaction with both acetyl acetone and ethylacetoacetate gave the corresponded 2-$(3^{I},5^{I}-dimethyl-1^{I}-pyrazoly$pyrimidine derivatives 20a-c and 24a-c respectively while the reaction with cinnamonitriles 25a-h afforded the corresponded aryl hydrazopyrimidines 27a-f. The structure of these reaction products were eatablished based on both elemental anlayses and spectral data studies.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.14-19
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• 1992

Diazotized primary artomatic amines 4 coupled with the ketosulfones 1-3 in ethanol in the presence of sodium acetate at $0^\circ{C}$ to afford the corresponding bydrazones 5-7. Also diazotized 3-aminopyrazoles 14 coupled with 1-3 in ethanolic sodium acetate to give the pyrazolotriazines 18-20 in good yields. Compounds 5-7 and 18 can also be obtained from the reaction of hydraziodoyl halides 8-10 and 21 with sodium benzenesultinate. The hydrazones 11-13 can easy be oxidized to the hydrazones 5-7, using hydrogen peroxide in acetic acid.