Microwave mediated facile synthesis of some novel pyrazole, pyrazolo [1,5-a] pyrimidine and pyrazolo [5,1-c][1,2,4] triazin derivatives

4-Phenyl-2H-pyrazol-3ylamine 3 has been prepared by reaction of 2-phenyl-3-piperidine-1-yl-acrylonitrile [6] with hydrazine hydrate under microwave irradiation. Compound 3 reacted with acetylacetone and ethyl acetoacetate to yield pyrazolopyrimidine derivatives 7 and 8, respectively. Pyrazolopyrimidine derivative II can be formed by reaction of 3 with 2-ethoxymethylene-malononitrile. Compound 3 can be diazotized to yield the diazonium chloride and coupled with 6 to yield pyrazolotriazine derivative 25. Structures of the synthesized compounds were confirmed by their IR and NMR spectroscopic data

2-Hydrazinopyiimidines as precursors for azolopyrimidines and pyrimidotriazines expected antimicrobial activity

Reaction of 2-hydrazino derivatives 2a,b with aromatic aldehydes afforded the arylhydrazone derivatives 3a-c which cyclized into triazolo derivatives 4a-c. Furthermore 2a,b reacted with aliphatic acids namely formic acid and acetic acid to yield the corresponding triazolo derivatives 5a-c and with nitrous acid to give the tetrazolo derivatives 6a,b. Compounds 6a,b were reduced by zinc dust to yield amines 7a,b. Also, compounds 2a,b reacted with carbon disulphide to yield the 3-triazolothione derivatives 8a,b. On the other hand, 2-hydrazino compounds 2a,b condensed with ethyl acetoacetate to afford 2-ethylacetoacetatdiydrazon derivatives 9a,b. Compound 9a cyclized by heating in ethanolic sodium ethoxide to yield 2-[l-pyrazolyl] derivative 10. Furthermore, compounds 2a,b reacted with phenacyl bromide to give triazinone derivative 11 and condensed with pentane-2, 4-dione to yield pyrazolyl derivatives 12a,b. Newly synthesized compounds 2b,5b,6b,7b and 9b exhibited promising biological activity

Synthesis, reactions and anticancer activity of some new heterobicylic nitrogen systems bearing acenaphtho [1,2-e] [1,2,4] triazine moiety, part I

Some new heterobicylic nitrogen systems, e.g. acetonitrile derivatives bearing acenaphtho [1,2-e] [1,2,4] triazine moiety have been synthesized and reacted with hydrazine hydrate, acetohydrazide, acids, alkalis, thiosemicarbazide and carbon disulphide. Structural assignment of the synthesized products 2-19 were confirmed by elemental analyses and spectral data [[1]H-NMR and [13]C-NMR determinations]. Some selected compounds showed remarkable anticancer activity

Synthesis of thienopyrimidotriazines, a new fused heterocyclic ring system

Benzothieno [2, 3: 4', 5'] pyrimido [2, l-c] [1, 2, 4] triazines 2, 4 and 6 which represent a new fused heterocyclic ring system were synthesized by reacting 2-hydrazino-5, 6, 7, 8-tertrahydrobenzothieno [2, 3-d]-pyrimidin-4 [3H]-one [1] with phenacyl bromide, bromomalononitrile or chloroacetyl chloride, respectively. Condensation of 6 with aromatic aldehydes produced arylmethylene derivatives 7a, b. Reaction of 1 with phthalic anhydride afforded the phthalazine derivative 8. Also, compound 1 reacted with beta- diketones and with ethyl acetoacetate to produce the pyrazolyl 9a-c and pyrazolinone derivatives 11, respectively. Compound 11 condensed with aromatic aldehydes and coupled with diazotized aromatic amines to afford the corresponding arylmethylene and arylazo derivatives 12 and 13, respectively. All compounds were confirmed by IR, HNMR and analytical data

Studies on ketene s,s,acetals. Part 1. synthesis of new pyrazol [1, 5 - 1] - pyrimidines and pyrazolo [1,5-a] triazines utilizing ketene s,s, acetals

In the present work, the new 3 [p-haloarylamino]4-methoxycarbonyl-5- aminopyrazole [3a-c] were obtained by using ketene S,S,acetal derivatives [1] as good precursors for the synthesis of p- haloarylaminomethoxycarbonyl methyl mercaptal [2a-c], which were prepared through displacement reaction of cyanomethoxycarbonyl ketene dithioacetal [1] with amines. The results of the study were given