One-Pot Reaction To Obtain N,N′-Disubstituted Guanidines of Pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine Scaffold as Human A3 Adenosine Receptor Antagonists

In this paper we describe an extension SAR study of pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine nucleus as A(3)AR antagonist. Our initial aim was to replace the phenylcarbamoyl moiety at the 5 position of PTP nucleus with a thiourea functionality to evaluate the contribution of new structural modification against the A(3)AR. The synthesized 12-25 were not characterized by the predicted side chain but by a 1,3-disubstituted guanidine and are shown to be interesting A(3)AR antagonists.