Nadia A. Abdel-Riheem

Synthesis and Antimicrobial Activity of Some New 5-Arylazothiazole, Pyrazolo[1,5-a] Pyrimidine, [1,2,4]Triazolo[4,3-a]Pyrimidine, and Pyrimido[1,2-a]Benzimidazole Derivatives Containing the Thiazole Moiety

1-(2-(4,5-Dihydro-3-(4-methyl-2-phenylthiazol-5-yl)-5-phenylpyrazol-1-yl)-4-substituted thiazol-5-yl)-2-phenyldiazene were synthesized from hydrazonoyl halides and 3-(4-methyl-2-phenyl-1,3-thiazol-5-yl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbothioamide in ethanolic triethylamine. Also, pyrazolo[5,1-a]pyrimidines, 2,3,6-trisubstituted pyridines, and pyrazolo[3,4-d]pyridazines were obtained from sodium salt of 3-hydroxy-1-(4-methyl-2-phenylthiazol-5-yl)prop-2-en-1-one and different heterocyclic amines. All structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, and alternative synthetic route whenever possible. The newly synthesized compounds were tested towards different microorganisms. Supplemental materials are available for this article. Go to the publishers online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

Reactions with Hydrazonoyl Halides 40: Synthesis of Some New 1,3,4‐Thiadiazoles, Pyrrolo[3,4‐c]pyrazoles, Pyrazoles, and Pyrazolo[3,4‐d]pyridazines

Abstract Pyrazoles, pyrazolo[3,4‐d]pyridazines, pyrrolo[3,4‐d]pyrazole‐4,6‐diones, and 2,3‐dihydro‐1,3,4‐thiadiazoles were synthesized via reactions of hydrazonoyl bromide with each of (2E)‐3‐(dimethylamino)prop‐2‐enoyl]benzo[f]2H‐chromen‐3‐one, N‐arylmaleimides, and alkyl carbodithioates.

Reactions of Hydrazonoyl Halides 35 1 : Synthesis of Some New 1,2,4-Triazolino[4,3-a]pyrimidines, 2,3-Dihydro-1,3,4-thiadiazoles and 2,3-Dihydro-1,3,4-selenadiazoles

Hydrazonoyl halides have been caused to react with each of ethyl 4-(2 H -benzo[3,4- d ]1,3-dioxolen-5-yl)-6-methyl-2-methylthio-3,4-dihydropyrimidin-5-carboxylate, potassium thiocyanate (or thiourea), potassium selenocyanate, and alkyl carbodithioate in the presence of triethylamine to give 4,3-dihydro-1,2,4-triazolino[4,3- a ]pyrimidine, 1,3,4-thiadiazoline, 1,2,4-selenadiazoline, and unsymmetrical azine derivatives in good yields. Structures of the new compounds were elucidated on the basis of elemental analyses, spectral data, and alternative methods of synthesis whenever possible.

Synthesis of New 3-Heteroarylindoles as Potential Anticancer Agents

2-(3-(1H-Indol-3-yl)-5-(p-tolyl)-4,5-dihydro-1H-pyrazol-1-yl)-4-substituted-5-(substituted diazenyl)thiazoles and 2-(1H-indol-3-yl)-9-substituted-4,7-disubstituted pyrido[3,2-e][1,2,4]triazolo[4,3-a]pyrimidin-5(7H)-ones were synthesized via reaction of hydrazonoyl halides with each of 3-(1H-indol-2-yl)-5-(p-tolyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide and 7-(1H-indol-3-yl)-2- thioxo-5-substituted-2,3-dihydropyrido[2,3-d]pyrimidin-4(1H)-ones, respectively. Also, hydrazonoyl halides were reacted with N’-(1-(1H-indol-3-yl)ethylidene)-2-cyanoacetohydrazide to afford 1,3,4-thiadiazole derivatives. Structures of the new synthesis were elucidated on the basis of elemental analysis, spectral data, and alternative synthetic routes whenever possible. Fifteen of the new compounds have been evaluated for their antitumor activity against the MCF-7 human breast carcinoma cell line. The results indicated that many of the tested compounds showed moderate to high anticancer activity when compared with doxorubicin as a reference drug.

Utility of 2-(5-methyl-1-phenyl-1H-pyrazol-4-yl)-2-oxo-N′-phenylaceto-hydrazonoyl bromide as precursor for synthesis of new functionalized heterocycles

ABSTRACT 2-(5-Methyl-1-phenyl-1H-pyrazol-4-yl)-2-oxo-N′-phenylaceto-hydrazonoyl bromide was synthesized and used as precursor for synthesis of some new 1,3,4-thiadiazoles, pyrrolo[3,4-c]pyrazoles, and 1,2,4-triazolo[4,3-a]pyrimidines. The mechanisms that account for formation of products were discussed. Also, the structures of all the newly synthesized products were confirmed based on elemental analysis, spectral data and by alternative methods. GRAPHICAL ABSTRACT

Synthesis of Some New 1,3,4-Thiadiazole, Thiazole and Pyridine Derivatives Containing 1,2,3-Triazole Moiety

In this study, 1-(5-Methyl-1-(p-tolyl)-1H-1,2,3-triazol-4-yl)ethan-1-one, was reacted with Thiosemicarbazide, alkyl carbodithioate and benzaldehyde to give thiosemicarbazone, alkylidenehydrazinecarbodithioate and 3-phenylprop-2-en-1-one-1,2,3-triazole derivatives. The 1,3,4-thiadiazole derivatives containing the 1,2,3-triazole moiety were obtained via reaction of alkylidenecarbodithioate with hydrazonoyl halides. Also, hydrazonoyl halides were reacted with thiosemicarbazone and pyrazolylthioamide to give 1,3-thiazoles derivatives. Subsequently, 3-phenyl-2-en-1-one was used to synthesize substituted pyridines and substituted nicotinic acid ester. The latter was converted to its azide compound which was reacted with aromatic amines and phenol to give substituted urea and phenylcarbamate containing 1,2,3-triazole moiety. The newly synthesized compounds were established by elemental analysis, spectral data and alternative synthesis whenever possible.

Synthesis of some new pyrazolo[1,5- a ]pyrimidine, pyrazolo[5,1- c ]triazine, 1,3,4-thiadiazole and pyridine derivatives containing 1,2,3-triazole moiety

BackgroundPyrazolo[1,5-a]pyrimidines are purine analogues. They have beneficial properties as antimetabolites in purine biochemical reactions. This division compounds have attracted wide pharmaceutical interest because of their antitrypanosomal activity.ResultsThe present work depicts an effective synthesis convention of pyrazolo[1,5-a]pyrimidines, pyrazolo[5,1-c]triazines, thieno[2,3-b]pyridines and polysubstituted pyridines containing 1,2,3,-triazole moiety from the reaction of sodium 3-(5-methyl-1-(p-toly)-1H-1,2,3-triazol-4-yl)-3-oxoprop-1-en-1-olate with the fitting heterocyclic amines and its diazonium salt, and active methylene compounds, individually. Likewise, thiazoles and, 1,3,4-thiadiazoles were obtained from 2-bromo-1-(5-methyl-1-(p-tolyl)-1H-1,2,3-triazol-4-yl)ethanone and some reagent such as hydrazonoyl chlorides and halo ketones. The newly synthesized compounds were established by elemental analysis, spectral data, and alternative synthetic route whenever possible.ConclusionsNew series of pyrazolo[1,5-a]pyrimidines, pyrazolo[5,1-c]triazines, thieno[2,3-b]pyridines and polysubstituted pyridines containing the 1,2,3,-triazole moiety were synthesized via reactions of sodium 3-(5-methyl-1-(p-toly)-1H-1,2,3-triazol-4-yl)-3-oxoprop-1-en-1-olate with the appropriate heterocyclic amines and its diazonium salt. In addition, 1,3,4-thiadiazoles and, 1,3-thiazoles were acquired in a decent yield via the reaction of substituted thiourea with the appropriate hydrazonoyl chlorides and halogenated ketenes.Graphical abstractSynthesis of some new pyrazolo[1,5-a]pyrimidines, pyrazolo[5,1-c]triazines and thieno[2,3-b]pyridines.