Novel Bridgehead Thiadiazolopyrimidine Derivatives with Antimicrobial and Antitumor Activities

Abstract

Because of the remarkable pharmacodynamics and chemotherapeutics activities of thiadiazolopyrimidines, a new series of 1,3,4‐thiadiazolo[3,2‐a] pyrimidine derivatives have been synthesized by reacting 5‐substituted‐2‐aminothiadiazoles 1a,b with different reagents: active methylenic compounds, benzaldehyde under different conditions, isatin, and cyclic ketones. The structures of the novel compounds have been inferred by spectroscopic methods (infrared, 1H‐NMR, 13C‐NMR, and mass spectrometry) and elemental analyses. The newly synthesized compounds were screened against four bacterial strains (Staphylococcus aureus and Listeria monocytogenes as Gram positive and Pseudomonas aeruginosa and Salmonella typhimurium as Gram negative) and two fungi (Aspergillus niger and Candida albicans) using agar diffusion assay. Most of the compounds showed activity against the tested microorganisms with different extents. The in vitro anticancer activities of these compounds were assessed against four human tumor cell lines; they were found to exhibit different cytotoxic effects. Such results mean that these derivatives can be further utilized as promising anticancer agents.

Green synthesis and characterisation of novel [1,3,4]thiadiazolo/benzo[4,5]thiazolo[3,2-a]pyrimidines via multicomponent reaction using vanadium oxide loaded on fluorapatite as a robust and sustainable catalyst

“…34 Azab et al have reported a two-step method for 5H-1,3,4-thiadiazolo[3,2-a] pyrimidin-5-ones, which involved the reaction of 2-amino-1,3,4-thiadiazoles to ethyl cyanoacetate and tandem reduction and deamination in the presence of phosphorus pentoxideformic acid. 35 Zhao et al have described the synthesis of 5H- [1,3,4]thiadiazolo [3,2-a]pyrimidine-6-carboxylate derivatives using aldehydes, 2-amino-thiadiazole and acetoacetate by onepot MCR strategy under microwave irradiation. 36 The synthesis of anticancer compounds, 7-substituted-phenyl-8,8adihydro-7H- [1,3,4]thiadiazolo [3,2-a]pyrimidine-6-carbonitriles was achieved by Tiwari and co-workers from the one-pot reaction of 5-(4-chlorophenyl)-1,3,4-thiadiazol-2 amine, aromatic aldehydes and malononitrile under ultrasonic irradiation and NaOH.…”

Multi‐component Reactions, Solvent‐free Synthesis of Substituted Pyrano‐pyridopyrimidine under Different Conditions Using ZnO Nanoparticles

“…Multi-component reactions are special types of synthetic organic strategies in which three or more reactants react to give a final product in one-pot procedure [1][2][3][4]. Pyrimidinones (Biginelli compounds) derivatives are of considerable interest, as they are a class of natural and synthetic compounds that possess a great variety of biological and pharmaceutical activities [5][6][7][8][9][10][11][12][13][14][15][16].…”

“…Amino-4-(4-chlorophenyl)-5-oxo-4H,5H-pyrano[2,3-d] pyrido[1,2-a] pyrimidine-3-carbonitrile(2). Anal.…”

Utility of Benzoxazin‐4‐one and 3‐Aminoquinazolin‐4‐one Derivatives as Precursors for Construction of Potent Insecticidal Heterocycles

“…From biological aspects, previous studies have reported that quinazolinone derivatives exhibited a pharmacological properties such as antitumor [13], anti-inflammatory [14][15][16], anticonvulsant [17,18], anti-HIV [19,20], antihypertensive [21][22][23], diuretic agent [24], antitubercular [25], antibacterial [26][27][28][29], and antitumor activities [29][30][31]. As a result of the aforementioned facts and in continuation for our program in the synthesis of biologically active heterocyclic systems [32][33][34][35][36][37][38][39], 2-pentylbenzoxazin-4-one 1 and 3-amino-2-pentylquinazolin-4-one 6 were used as a versatile key staring for the synthesis of novel heterocyclic compounds. The structure of the newly synthesized compounds were elucidated from elemental analyses and different spectroscopic data (infrared [IR], 1 H-NMR, 13 C-NMR, and mass spectrometry [MS]).…”