Abstract Some new 7-alkyl-4, 6-dihydropyrazolo [4′, 3′: 5, 6] pyrano [2, 3-d] pyrimidin-5 (1
H)-ones were prepared through heterocyclization of 6-amino-1, 4-dihydropyrano [2, 3-c] …

A one-pot and efficient method for the synthesis of pyrazolo [4′, 3′: 5, 6] pyrido [2, 3-d]
pyrimidine-dione derivatives by condensation reaction of barbituric acids, 1H-pyrazol-5 …

One pot synthesis of 1-arylpyrazolo [3, 4-d] pyrimidin-4-ones by the reaction of 5-amino-N-
substituted-1 H-pyrazole-4-carbonitrile with different lower aliphatic acids in the presence of …

Benzyl‐and 2‐aryloxymethyl‐3‐amino‐1‐phenyl‐pyrazolo [3, 4‐d] pyrimidine‐4‐ones 5a–f
have been synthesized by reacting the corresponding arylacetylamino derivatives 3a–f with …

A series of new pyrazolo [1, 5-a] pyrimidine derivatives has been synthesized by using 7-
hydrazinyl-5-methylpyrazolo [1, 5-a] pyrimidine-3-carbonitrile 1 and 7-amino-5 …

The desired fused ring system 3-isopropyl-4-aryl-1, 4, 5, 7-tetrahydropyrazolo [3, 4-d]
pyrimidin-6-ones 4a-d have been synthesized by the reaction of 5-isopropyl-2, 4-dihydro-3 …

A new synthetic route is proposed for the synthesis of 3, 6-dimethyl-6-aryl-1, 5, 6, 7-
tetrahydro-8H-pyrazolo [3', 4': 4, 5] thieno [2, 3-d] pyrimidin-8-ones 3a-h from 5-amino-3 …

Amino-5-bromo-4, 6-dimethyl-1H-pyrazolo [3, 4-b] pyridine (2) was utilized as a precursor for
the construction of new polyheterocyclic ring systems. It reacted with 4-substituted arylidene …

An efficient and environmental benign regioselective synthesis of some new pyrazol-1′-
ylpyrazolo [1, 5-a] pyrimidines (7b–h) has been accomplished via treatment of 3 (5)-amino-5 …

An efficient one-pot methodology for the synthesis of pyrazolo [3, 4-d] pyrimidines was
developed by using 5-aminopyrazoles with formamide in presence of PBr3 as the coupling …