A new and facile synthetic approach to substituted 2-thioxoquinazolin-4-ones by the annulation of a pyrimidine derivative

Abstract

SummaryA new and facile synthesis of 2-thioxoquinazolin-4-ones by introducing a benzenoid system in the pyrimidine moiety by reacting ethoxymethylene derivatives of 1,3-diarylthiobarbituric acids (DTBA) with active methylene compounds, such as malononitrile and ethyl cyanoacetate, in presence of ZnCl2 has been developed.

Trisubstituted barbiturates and thiobarbiturates: Synthesis and biological evaluation as xanthine oxidase inhibitors, antioxidants, antibacterial and anti-proliferative agents

“…Table S1). The majority of 5-substituted BAD and TBAD families described herein are known precursors of fused heterocycles reported in the literature [10,12,13,15,[17][18][19][20][21][22][23][24].…”

“…and C5, the latter being the most studied position. Within these structural modifications, various cyclization reactions at C5 and C6 of BA, thiobarbituric acid (TBA) and their derivatives (BADs and TBADs, respectively) [10][11][12][13][14][15][16][17][18][19] as well as at C5 with spiro formation [20][21][22][23][24] have been described. Interestingly, some of these transformations involve a multicomponent reaction (MCR) [11,14,16].…”

“…Interestingly, some of these transformations involve a multicomponent reaction (MCR) [11,14,16]. However, in most cases, the cyclization path is preceded by the formation of substituted methyl [10,18], arylidene [12,15,[19][20][21][22][23][24], or methylene [13,17,19] derivatives at C5 as key isolated or potential precursors of these modified pyrimidines.…”

“…Within these, hydrazone BADs have the ability to inhibit fungal growth in the μM range [28]. In addition, through the introduction of urea, thiourea, guanidine, hydrazine or hydroxylamino groups to BADs and TBADs, new bioactive compounds can be obtained [13,17,29].…”

KF/Al2O3 Catalyzed One-Pot Three-Component Process for the Synthesis of Some 2-Thioxoquinazolin-4(1H)-one Derivatives

“…The quinazolinones scaffold are important class of fused heterocycles with a show promise such as antiinflammatory 4 , antimalarial 5 , anti HIV 6 and anti cancer 7 and dihydrofolate reductase inhibitors 8 . Moreover, few methods are reported for the synthesis of 2-thioxoquinazolin-4-ones, as most of the methods reported are for quinazolin-2,4(1H,3H)diones 9,10 .…”