71509-22-3

Upstream product

• 134653-70-6 ethyl 2-[(dimethylamino)methylene]-3-oxobutanoate 
• 1572-10-7 3⁽⁵⁾-phenylpyrazol-5⁽³⁾-amine 
• 827-41-8 3-phenylpyrazol-5-amine 
• 3788-94-1 2-ethoxymethylene-3-oxobutanoic acid ethyl ester 

Downstream Products

• 870972-92-2 6-acetyl-7-hydroxy-2-phenylpyrazolo[1,5-a]pyrimidine 
• 71509-27-8 7-Methyl-2-phenylpyrazolo<1,5-a>pyrimidine 
• 71509-26-7 7-methyl-2-phenylpyrazolo[1,5-a]pyrimidine-6-carboxylic acid 

Relevant academic research and scientific papers

COMPOUND INHIBITING DIPEPTIDYL PEPTIDASE IV

The invention aims to provide a dipeptidyl peptidase IV inhibitor which is satisfactory in respect of activity, stability and safety and has an excellent action as a pharmaceutical agent. The invention is directed to a compound represented by the following general formula or a pharmaceutically acceptable salt thereof: wherein R1 and R2 each represents hydrogen, an optionally substituted C1-6 alkyl group, or -COOR5 whereupon R5 represents hydrogen or an optionally substituted C1-6 alkyl group, or R1 and R2, together with a carbon atom to which they are bound, represent a 3- to 6-membered cycloalkyl group, R3 represents hydrogen or an optionally substituted C6-10 aryl group, R4 represents a hydrogen or a cyano group, D represents -CONR6-, -CO- or -NR6CO-, R6 represents hydrogen or an optionally substituted C1-6 alkyl group, E represents -(CH2)m- whereupon m is an integer of 1 to 3, -CH2OCH2-, or -SCH2-, n is an integer of 0 to 3, and A represents an optionally substituted bicyclic heterocyclic group or bicyclic hydrocarbon group.

Recyclization of condensed carbethoxypyrimidines accompanied by substitution of a carbon atom into the heterocycle

Condensation in ethanol of ethyl ethoxymethyleneacetoacetate with systems containing an amidine fragment (substituted 3-aminopyrazoles and 3-amino-1,2,4-triazole) gave 6-carbethoxy-7-methylpyrazolo[1,5-a]pyrimidines. Addition of base to solutions of the o

α-Aminoazoles in the synthesis of heterocycles: I. Synthesis of regioisomeric 5-methyl-2,7-diphenyl-and 7-methyl-2,5-diphenylpyrazolo[1,5-a]pyrimidines

4-Phenyl-3-butyn-2-one reacts with 3(5)-amino-5(3)-phenylpyrazole on heating in DMSO to give 7-methyl-2,5-diphenylpyrazolo[1,5-a]pyrimidine. The reaction of 3(5)-amino-5(3)-phenylpyrazole with benzoylacetone in chloroform, ethanol, and DMSO results in formation of a mixture of isomeric pyrazolopyrimidines, the major product being 5-methyl-2,7-diphenylpyrazolo[1,5-a]pyrimidine.

Reactivity of 7-(2-Dimethylaminovinyl)pyrazolopyrimidines: Synthesis of Pyrazolopyridopyrimidine Derivatives as Potential Benzodiazepine Receptor Ligands. 2.

A series of pyrazolopyridopyrimidin-6-ones was obtained by reaction of ammonium acetate with ethyl 7-dimethylaminovinylpyrazolopyrimidine-6-carboxylates and these had been prepared from ethyl 7-methylpyrazolopyrimidine-6-carboxylates by reaction with dimethylformamide dimethylacetat.Under these conditions the compounds bearing a 2-hydroxy group were also O-alkylated.During the preparation of the ethyl 2-hydroxy-7-methyl-3-phenylpyrazolopyrimidine-6-carboxylate the corresponding 5-methyl isomer was isolated and identified.

Unambiguous Structure Determination of Some Pyrazolopyrimidine Derivatives by Multinuclear NMR Spectroscopy

The condensation of 3(5)-aminopyrazole and 5-amino-3-phenylpyrazole with ethyl 2,4-dioxopentanoate and 2-ethoxymethylidene-3-oxobutyrate has been re-investigated.Contrary to previous reports, the former reaction gives rise to both regioisomeric pyrazolo1