A synthesis of 6-functionalized 4,7-dihydro[1,2,4]triazolo[1,5-a]pyrimidines

An Overview on Synthetic and Medicinal Perspectives of [1,2,4]Triazolo[1,5‐a]pyrimidine Scaffold

“…reported the cyclization reaction of 1 H ‐1,2,4‐triazol‐5‐amine ( R16 ) with benzaldehyde and 2,4‐dioxo‐4‐(phenylamino)butan‐1‐ylium in presence of catalytic amount of 25 mol.% of maltose to achieve P16 (5‐methyl‐ N ,7‐diphenyl‐4,7‐dihydro‐[1,2,4]triazolo[1,5‐ a ]pyrimidine‐6‐carboxamide) (route‐16) [34] . Kolosov and co‐workers obtained the desired final compound P17 (5,7‐dimethyl‐6‐(phenylsulfonyl)‐4,7‐dihydro‐[1,2,4]triazolo[1,5‐ a ]pyrimidine) via treating 1 H ‐1,2,4‐triazol‐5‐amine ( R17 ) with acetaldehyde and 1‐(phenylsulfonyl)propan‐2‐one in presence of DMF‐H 2 O under heat conditions (route‐17) [35] …”

Bi2O3/FAp, a sustainable catalyst for synthesis of dihydro‐[1,2,4]triazolo[1,5‐a]pyrimidine derivatives through green strategy

“…Development of methods for dihydro‐[1,2,4]triazolo‐pyrimidines synthesis has received incredible attention of synthetic chemists for their broad spectrum of biological and pharmacological profiles, which include anticancer, antibacterial, antiproliferative, anti‐HIV, and fungicidal activities . Most synthetic protocols involved the MCR between active methylene substrate, aldehyde, and various amine compounds in the presence of different heterogeneous catalysts, bases, and solvents to synthesize bioactive core moieties . In recent years, there is considerable interest toward the developing synthetic protocols for new dihydropyrimidine scaffolds.…”

“…[13][14][15][16][17][18] Most synthetic protocols involved the MCR between active methylene substrate, aldehyde, and various amine compounds in the presence of different heterogeneous catalysts, bases, and solvents to synthesize bioactive core moieties. [19,20] In recent years, there is considerable interest toward the developing synthetic protocols for new dihydropyrimidine scaffolds. Various materials including…”

Ultrasonic-assisted unusual four-component synthesis of 7-azolylamino-4,5,6,7-tetrahydroazolo[1,5-a]pyrimidines

“…Furthermore, tetrahydropyrimidines containing fused azole rings are a privileged class of heterocycles due to their antiviral [2], antitubercular, antitumor [3], antibacterial [4,5], and boneanabolic activities [6,7]. Previously, some tetrahydroazolopyrimidines II (Scheme 1) were synthesized using sequential synthetic routes [8][9][10][11][12][13][14][15], in most cases involving the reduction of the dihydroazolopyrimidines I obtained via well-known reactions of aminoazoles with α,β-unsaturated ketones [8][9][10][11] or via their multicomponent analogues. On the other hand, multicomponent reactions (MCRs) directly leading to tetrahydroazolopyrimidine heterocyclic systems have also been published [4,5,[16][17][18][19][20][21][22][23][24].…”