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Background: Pyrazole and its derivatives are known to exhibit significant biological and pharmacological activities such as anticancer, anti-inflammatory, antioxidant, antibacterial, analgesic, antiviral, antimicrobial, antifungal, anti-glycemic, antiamoebic, and antidepressive. Considering the immense biological properties, pyrazole is one of the most widely studied nitrogen- containing heterocyclic nuclei. Fused pyrazole derivatives are composed of the pyrazole nucleus attached to other heterocyclic moieties., Objective: The objective of this article is the synthesis of some new pyrazolo[1,5-a]pyrimidine and pyrazolo[5,1-c]1,2,4-triazine derivatives with potential anticancer and antimicrobial activities., Methods: The in vitro growth inhibitory rates (%) and inhibitory growth activity (as measured by IC50) of the newly synthesized compounds were determined against the MCF-7 human breast carcinoma cell line in comparison with the well-known anticancer drug doxorubicin as the standard, using the MTT viability assay. The data generated were used to plot a dose-response curve from which the concentration (μM) of tested compounds required to kill 50% of the cell population (IC50) was determined. Cytotoxic activity was expressed as the mean IC50 of three independent experiments. The difference between inhibitory activities of all compounds with different concentrations was statistically significant p < 0.001. All compounds were structurally characterized by different spectroscopic techniques EI-MS, 1H-NMR, and 13C-NMR, and evaluated for their anticancer and antimicrobial activities (antibacterial and antifungal)., Results: Several pyrazolo[1,5-a]pyrimidine derivatives were synthesized from the reaction of 2-(4- (5-amino-1H-pyrazol-3-yl)phenyl)-1H-indene-1,3(2H)-dione with the appropriate active methylene compounds in boiling ethanol. Also, pyrazolo[5,1-c]triazines were obtained through the reaction of 2-(4-(5-(chlorodiazenyl)-1H-pyrazol-3-yl)phenyl)-1H-indene-1,3(2H)-dione with various active methylene compounds in ethanol containing sodium acetate at 0-5 oC. The structures of the newly synthesized compounds were elucidated on the basis of elemental analysis, spectral data, and alternative synthetic routes whenever possible. The newly synthesized compounds were evaluated for their antitumor activity against a breast cancer cell line (MCF-7) and a human colon cancer cell line (HCT-116). The results revealed that the tested compounds showed high variation in the inhibitory growth rates and activities against the tested tumor cell lines. All newly synthesized compounds screen towards microorganisms e.g. Gram-negative bacteria, Gram-positive bacteria, and Fungi., Conclusion: 2-(4-(5-Amino-1H-pyrazol-3-yl)phenyl)isoindoline-1,3-dione proved to be a useful precursor for the synthesis of various pyrazolo[1,5-a]pyrimidine and pyrazolo[5,1-c]-1,2,4- triazines. The structures of the newly synthesized compounds were confirmed by spectral data and elemental analyses. The newly synthesized compounds were tested in vitro against the MCF-7, HCT-116 human cancer cell line and compared with doxorubicin as the standard, using the MTT viability assay. Most of the tested compounds were found to have moderate to high anticancer activity., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

A novel series of 1,3,4-thiadiazoles, 5-arylazothiazoles and hexahydropyrimido-[4,5-d][1,2,4]triazolo[4,3-a]pyrimidines were synthesized via reaction of hydrazonoyl halides with each of alkyl carbothioates, carbothioamides and 7-thioxo-5,6,7,8-tetrahydropyrimido-[4,5-d]pyrimidine-2,4(1H,3H)-diones in the presence of triethylamine. The structures of the newly synthesized compounds were established based on their spectral data, elemental analyses and alternative synthetic routes whenever possible. Also, the newly synthesized compounds were screened for their antimicrobial activity against various microorganisms.

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. [ABSTRACT FROM AUTHOR]

Pyrazolo[3,4- d]pyridazines, isoxazolo[3,4- d]pyridazines, azolo[1,5- a]pyrimidines, azolo[5,1- c]triazines, pyrazoles, and benzo[ b][l,4]diazepine were synthesized from the appropriate hydrazonoyl halides, hydroximoyl halides, heterocyclic amines, diazotized heterocyclic amines, arenediazonium chlorides, and o-phenylenediamines with appropriate of sodium 3-(5-bromobenzofuran-2-yl)-3-oxoprop-1-en-1-olate or 1-(5-bromobenzofuran-2-yl)-3-(dimethylamino)prop-2-en-1-one. The newly synthesized compounds were elucidated by elemental analyses, spectral data, and alternative synthesis whenever possible. [ABSTRACT FROM AUTHOR]

1,3,4-Thiadiazoles, pyrazolo[1,5- a]pyrimidines, pyrazolo[5,1- c]triazine, and thieno[3,2- d]pyrimidines were synthesized from 1-(5-bromobenzofuran-2-yl)ethanone. The structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, chemical transformation, and alternative synthesis route whenever possible. [ABSTRACT FROM AUTHOR]

Synthesis of pyrazolo[1,5- a]pyrimidines, [1,2,4]triazolo[1,5- a]pyrimidine, 8,10-dimethyl-2-(5-methyl-1-phenyl-4,5-dihydro-1 H-1,2,3-triazol-4-yl)pyrido[2′,3′:3,4]-pyrazolo[1,5- a]pyrimidine, benzo[4,5]imidazo[1,2- a]pyrimidine via heterocyclic amines, and sodium 3-hydroxy-1-(5-methyl-1-phenyl-1 H-1,2,3-triazole-4-yl)prop-2-en-1-one were carried out. Also, synthesis of isoxazoles, and pyrazoles from sodium 3-hydroxy-1-(5-methyl-1-phenyl-1 H-1,2,3-triazole-4-yl)prop-2-en-1-one and hydroxymoyl chlorides and hydrazonoyl halides, respectively, were made. Analogously, (1,2,3-triazol-4-yl)thieno[2,3- b]pyridine derivatives were obtained from sodium 3-hydroxy-1-(5-methyl-1-phenyl-1 H-1,2,3- triazole-4-yl)prop-2-en-1-one and cyanothioacetamide followed by its reacting with active methylene compounds. In addition to full characterization of all synthesized compounds, they were tested to evaluate their antimicrobial activities, and some compounds showed competitive activities to those of tetracycline, the typical antibacterial drug, and clotrimazole, the typical antifungal drug. [ABSTRACT FROM AUTHOR]

Coumarin derivatives containing pyrazolo[1,5-a]pyrimidine, tetrazolo[1,5-a]pyrimidine, imidazo[1,2-a]pyrimidine, pyrazolo[3,4-d]pyrimidine, 1,3,4-thiadiazoles and thiazoles were synthesized from 6-bromo-3-(3-(dimethylamino)acryloyl)-2H-chromen-2-one, methyl 2-(1-(6-bromo-2-oxo-2Hchromen- 3-yl)ethylidene)hydrazine carbodithioate, 2-(1-(6-bromo-2-oxo-2H-chromen-3-yl)ethylidene) hydrazine carbothioamide and each of heterocyclic amine, hydrazonoyl chlorides and hydroximoyl chlorides. The structures of the newly synthesized compounds were elucidated on the basis of elemental analysis, spectral data, and alternative synthetic routes whenever possible. Moreover, selected newly synthesized products were evaluated for their antitumor activity against a liver carcinoma cancer cell line (HEPG2-1). The results revealed that pyrazolo[1,5-a]pyrimidine 7c, thiazole 23g and 1,3,4-thiadiazole 18a (IC50 = 2.70 ± 0.28, 3.50 ± 0.23 and 4.90 ± 0.69 µM, respectively) have promising antitumor activity against liver carcinoma (HEPG2-1) while most of the tested compounds showed moderate activity. [ABSTRACT FROM AUTHOR]

Condensation of sodium 3-oxo-3-(1-phenyl-1H-pyrazol-4-yl)prop-1-en-1-olate (2) with several heterocyclic amines, cyanoacetamide, cyanothioacetamide, and 2-cyanoacetohydrazide gives pyrazolo[1,5-a]pyrimidines (5a-d), pyrido[2',3':3,4]pyrazolo[1,5- a]pyrimidine (9), benzo[4,5]imidazo[1,2-a]pyrimidine (10), [1,2,4]triazolo[1,5-a]pyrimidine (11), and pyridine derivatives (12-14). Also, thieno[2,3-b]pyridines (15-18) were synthesized via pyridinethione (13) with α-halo ketones and α-halo ester. Structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, alternative synthetic routes, and chemical transformation whenever possible. [ABSTRACT FROM AUTHOR]

Naphtho[2,1- b]furan-2-yl)(8-phenylpyrazolo[5,1- c][1,2,4]triazin-3-yl)methanone, ([1,2,4]triazolo[3,4- c][1,2,4]triazin-6-yl)(naphtho[2,1- b]furan-2-yl)methanone, benzo[4,5]imidazo[2,1- c][1,2,4]triazin-3-yl-naphtho[2,1- b]furan-2-yl-methanone, 5-(naphtho[2,1- b]furan-2-yl)pyrazolo[1,5- a]pyrimidine, 7-(naphtho[2,1-b]furan-2-yl)-[1,2,4]triazolo[4,3-a]pyrimidine, 2-naphtho[2,1- b]furan-2-yl-benzo[4,5]imidazo[1,2- a]pyrimidine, pyridine, and pyrazole derivatives are synthesized from sodium salt of 5-hydroxy-1-naphtho[2,1- b]furan-2-ylpropenone and various reagents. The newly synthesized compounds were elucidated by elemental analysis, spectral data, chemical transformation, and alternative synthetic route whenever possible. J. Heterocyclic Chem., (2012). [ABSTRACT FROM AUTHOR]

2,3-Dihydro-1,3,4-thiadiazoles, 2,3-dihydro-1,3,4-selenadiazoles, and triazolino[4,3-a]pyrimidines containing benzoxazole or benzothiazole moieties were prepared from the reaction of each of ethyl 3-aza-3-(benzoxazol-2-ylamino)-2-chloroprop-2-enoate and ethyl 3-aza-3-(benzothiazolo-2-ylamino)-2-chloroprop-2-enoate with each of potassium thiocyanate, potassium selenocyanate, alkyl carbodithioate, and pyrmidine-2-thione derivatives. All the newly synthesized compounds were confirmed by elemental analysis, spectral data, and alternative route synthesis whenever possible. Some of the newly synthesized compounds were screened toward certain cancer tumors. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

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 publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. [ABSTRACT FROM AUTHOR]

3-Arylazo-2-(4-methyl-2-phenylthiazol-5-yl)imidazo[1,2-a]pyrimidine, 2-(4-methyl-2-phenyl-1,3-thiazol-5-yl)-3-phenylazoimidazo[1,2-a]pyridine, 3-arylazo-2-(4-methyl-2-phenylthiazol-5-yl)-6-phenyl-5Himidazo[1,2-b]pyrazole, 6-(4-methyl-2-phenyl-thiazol-5-yl)-5-phenylazo3-phenyl-imidazo[2,1-b]thiazole, 3-(4-methyl-2-phenylthiazol-5-yl)-2-phenylhydrazino-(1H)-quinoxaline, 3-(4-methyl-2-phenylthiazol-5-yl)- 2-phenylazoquinoxaline, 3-(4-methyl-2-phenylthiazol-5-yl)-2-phenylhydrazinobenzo-[1,4] thiazine, 3-(4-methyl-2-phenyl-thiazol-5-yl)-2-phenylhydrazinobenzo[1,4]oxazine, and 3-(4-methyl-2-phenylthiazol-5-yl)-2-phenylazo-1H-pyrido[2,3-b]pyrazine derivatives were synthesized via reaction of 2-(4-methyl-2-phenyl-1,3-thiazol-5-yl)-2-oxo-N-arylethanehydrazonoyl bromide with each of 2-aminopyrimidine, 2-aminopyridine, 3-aminopyrazoles, 2-amino-4-phenylthiazole, o-phenylenediamine, o-aminothiophenol, o-aminophenol, or 2, 3-diaminopyridine, respectively. All structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, and alternative synthetic route whenever possible. The entire newly synthesized compounds are tested toward different microorganisms. [ABSTRACT FROM AUTHOR]

Thieno[2,3-b]pyridines were synthesized from 6-benzofuran-2-yl-4-phenyl-2-sulfanylpyridine-3-carbonitrile and each of chloro acetone, ethyl chloroacetate, ω -bromoacetophenone, and chloroacetonitrile. These compounds were conveniently converted into novel pyrido[4',5':4,5]thieno[3,2-d]pyrimidines. Also, 2,3-dihydro-1,3,4-thiadiazole was synthesized from hydrazonoyl halides and 2-benzofuran-2-yl-3-(phenylamino)-3-thioxopropanenitrile. The structures of the products have been elucidated by elemental analyses, spectral data studies, and alternative syntheses whenever possible. The newly synthesized compounds were tested towards microorganisms. [ABSTRACT FROM AUTHOR]

2-(5-imino-4-aryl-4,5-dihydro-[1,3,4]-thiadiazole-2-(carbonyl)benzo[f]chro-men-2-one, 2-(2-amino-5-arylazothiazol-4-yl)benzo[f]chromen-3-one and ethyl 6-methyl-3-oxo-benzo [f]chromen-2-yl)-1,4-dihydro-[1,2,4]triazolo[4,3-a]pyrimidine-5-carboxy- late were synthesized from hydrazonoyl bromides. Structures of the newly synthesized compounds were established by elemental analysis, spectral data and alternative synthesis route whenever possible. [ABSTRACT FROM AUTHOR]

6-(2-Naphtyl)-1-phenyl-4-3,5-disubstituted 4,3a-triazolino[4,3-a]pyrimidines, [2(1-(2-naphthyl)-5-substitued (1-pyrazolin-3-yl)-4-phenyl(thiazol-5-yl)phenyldiazine and 1-(2-aza-2-[4-phenyldiazenyl)-(1,3-thiazol-2-yl)]amino}vinyl)-naphthalene-2-ol were synthesized via reactions of hydrazonoyl halides with 4-(2-naphthyl)-6-substituted 3,4-dihydropyrimidine-2-thione, Amino(3-(2-naphthyl)-5-substituted pyrazolin-2-ylmethane-1-thione, and 2-hydroxynaphthalenecarbaldehyde-thiosemicarbazone. All structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, and alternative synthesis methods whenever possible. Some of the new compounds were tested towards bacteria. In general, all tested compounds were capable of highly inhibiting the growth of gram positive of bacteria and gram negative. [ABSTRACT FROM AUTHOR]

2,3-dihydro-1,3,4-thiadiazoles, triazolino[4, 3- a ] pyrimidines , andpyrazolo [3, 4- d ]pyridazines were synthesized in good yields from reactions of hydrazonoyl halides with alkyl carbodithioates, pyrimidine-2-thione, and substituted prop-2-ene-1-one, respectively. All structures of the newly synthesized compounds were elucidated by elemental analysis, spectral data, and an alternative synthesis method. Some of the new compounds were tested towards bacteria and fungi. [ABSTRACT FROM AUTHOR]

Triazoles, thiadiazoles, and triazolo[4, 3-a]pyrimidines were synthesized via reaction of hydrazonoyl halides with each of 3-methyl-4-(methylthiothioxomethyl)-2-pyrazolin-5-one, 3-methyl-4-[methylthio(phenylamino)methyl]-2-pyrazolin-5-one, and pyrimidine-2-thiones. Structures of the newly synthesized compounds were elucidated on the basis of elemental analysis, spectral data, and alternative-methods synthesis whenever possible. [ABSTRACT FROM AUTHOR]

Thiazolylacetonitrile was used in the synthesis of coumarin, pyrazolo[4,3]pyrimidines, 1,3,4-thiadiazolines, aminothiophenes, and thiazoles in a good yields. Also, pyrazolo[4,5- d ]triazolino[4,5- a ]pyrimidines, pyrazolo[4,5- d ]thiazolino[3,2-a]pyrimidines, and pyrazolo[4,5-d]tetrazolino[1,5-a]pyrimidines were synthesized from pyrazolo[4,5-d]pyrimidine. Structures of the newly synthesized were elucidated by elemental analysis, spectral data, and alternative synthesis routes whenever possible. Some synthesized compounds were tested for their antimicrobial activity. [ABSTRACT FROM AUTHOR]

2,3-Dihydro-1,3,4-thiadiazoles, 2,3-dihydro-1,3,4.selenadiazoles, unsymmetrical azines and triazolino[4,3-a]pyrimidines were prepared from reaction of (2Z)-3-aza-2-bromo-1-naptho[1,2-d]furan-2-yl-3-(phenylamino)prop-2-en-1- one (6) with each of potassium thiocyanate, potassium selenocyanate, alkyl carbodithioate, ethyl 6-methyl-2-methylthio-4-substituted 3,4-dihydropyrimidine-5-carboxylate or (ethyl 4-methyl-6-substituted 2-thione-1,3,6-trihydropyrimidine-5-carboxylate). All compounds were elucidated on the basis of elemental analysis, spectral data. and alternative synthesis method whenever possible. [ABSTRACT FROM AUTHOR]

1,3,4-Thiadiazolines, 1,3,4-selenadiazolines and triazolino[4,3-a]pyrimidines have been synthesized from 3-aza-[2,4-dimethyl(1,3-thiazol-5-yl) -2-bromo-3-substituted-amino]prop-2-en-1-ones with potassium thiocyanate, potassium selenocyanate, alkyl carbodithioates and 6-methyl-2-methylthio-4-substituted 3,4-dihydropyrimidine-5-carboxylates. Structures of the newly synthesized compounds have been established by elemental analysis, spectral data and alternative synthesis whenever possible. Some of products have been tested towards bacteria. [ABSTRACT FROM AUTHOR]

1,2,4-Triazolo[4,3-a]pyrimidines, thiadiazolines and selenadiazolines synthesized via reactions of hydrazonoyl halides with each of ethyl 4 - (3, 4- dimethoxyphenyl) -6-methyl -2-methylthio-3,4-dihydropyrimidine -5-carboxylate (or ethyl 6-(3,4-dimethylphenyl)-4-methyl-2-thio -1,3,6-trihydropyrimidine-5-carboxylate), ethyl 4-(2,3-dimethoxyphenyl) -6-methyl-2-methylthio-3,4-dihydropyrimidine-5-carboxylate, potassium thiocyanate, potassium selenocyanate, and carbodithioates respectively. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]