• Journal of the Korean Chemical Society
• /
• v.55 no.4
• /
• pp.719-722
• /
• 2011

• Archives of Pharmacal Research
• /
• v.20 no.4
• /
• pp.330-337
• /
• 1997

Thiocarboxamidocinnamonitrile derivatives 2 under bar a-f reacted with 3-aminopyrazole derivative 3 under bar a-c to give the pyrazole[3, 2-b]pyrimidine derivatives 6 under bar a-p. Compounds 6 under bar a-p were used as starting material for syntheses of several heterocylic coompounds. Dehydrogenation of 6 under bar gave pyrazole[3, 2-b]pyrimidines 10 under bar a-d while its reaction with diethyl oxalate gave 11 under bar. Reactions of 6 under bar with formic acid gave pyrazolopyrimidines 17 under bar a-j, and pyrazolopyrimidopyrimidines 18 under bar a-j.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.10
• /
• pp.1429-1432
• /
• 2003

A novel fused thiouracil containing a heterocyclic ring system, dipyrimidinopyridine (3), has been prepared through the cyclization of compound 2. Compound 2 was formed by the formylation of 6-amino-2-thiouracil 1, pyrazolopyrimidines 8-10 via the heating of 6-arylhydrazono-2-thiouracils 5-7, compound 11, using Vilsmeier reagent with compound 4, pyrazolylpyrimidine 12, indolodiazinopyrimidine 14 and pyridazinopyrimidine 15. Pyridazino-pyrimidine 15 was formed by the condensation of compound 4 with acetylacetone, isatin and benzyl, respectively.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.3
• /
• pp.561-566
• /
• 2009

Chloroacylation of 3-amino-2-phenylpyrazole-4-carboxamide (2) using chloroacetyl-(propionyl) chloride affording 6-chloromethyl(ethyl)-1-phenylpyrazolo[3,4-d]pyrimidin-4[5H]-one (3) or (6). Chlorine atom in compound (3) or (6) underwent nucleophilic substitution reaction with primary or secondary amines to give 6-alkyl(aryl)aminomethyl(ethyl)-1-phenylpyrazolo[3,4-d]pyrimidin-4[5H]-one (4a-g,7a-f). When arylaminomethyl( ethyl)pyrazolopyrimidine was treated with formaline (30%) solution in ethanol, underwent Mannich reaction to afford imidazopyrazolopyrimidines (5a-e) and pyrazolopyrimidopyrimidines (8a-e). Chloromethylpyrimidine derivative 3 was converted into the corresponding mercaptomethylpyrazolopyrimidene 9, Which cyclized using bromomalononitrile or phenacyl bromide into pyrazolopyrimidothiazine 11,12.