Facile green one‐pot synthesis of novel thiazolo[3,2‐a]pyrimidine derivatives using Fe₃O₄@l‐arginine and their biological investigation as potent antimicrobial agents

Abstract

Thiazolopyrimidine derivatives are well known because of their excellent therapeutic properties. In this investigation, an effective one‐pot three‐component method is described for the synthesis of novel 2‐[(Z)‐1‐(substituted phenyl)methylidine]‐7‐methyl‐3‐oxo‐5‐(substituted phenyl)‐2,3‐dihydro‐5H‐thiazolo[3,2‐a]pyrimidine‐6‐carboxilic acid tert‐butyl ester derivatives by condensation reaction of 3,4‐dihydropyrimidine‐2(1H)‐thiones, various aromatic aldehydes and chloroacetyl chloride under reflux conditions in the presence of Fe3O4@l‐arginine nanoparticles as a magnetically reusable and eco‐friendly catalyst with short reaction times and moderate yields. The chemical structures of all synthesized compounds were determined using infrared, 1H NMR and 13C NMR spectroscopies. In vitro antimicrobial activities of 3,4‐dihydropyrimidine‐2(1H)‐thiones and newly fused thiazolo[3,2‐a]pyrimidine derivatives were examined using the well diffusion method against diverse pathogenic strains, namely Staphylococcus aureus ATCC 6538, S. epidermidis ATCC 12228, Escherichia coli ATCC 8739 and Pseudomonas aeruginosa ATCC 9027 (bacteria), Candida albicans ATCC 10231 (yeast) and Aspergillus niger ATCC 16404 (fungus). The compounds having 2‐hydroxy, 4‐hydroxy, 2‐chloro and 4‐chloro groups attached to the phenyl ring on the pyrimidine and 4‐CH3, 4‐OCH3 and 3‐NO2 groups attached to benzylidine on the thiazolo moiety showed significant antibacterial activity.

Fe3O4@L‐arginine magnetic nanoparticles: A novel and magnetically retrievable catalyst for the synthesis of 1′3‐diaryl‐2N‐azaphenalene

“…We have developed a facile, rapid, and efficient method for synthesis of 1,3‐diaryl‐2‐azaphenalene derivatives in good to high yield via Fe 3 O 4 @ L ‐arginine as a nanocatalyst. L ‐Arginine‐coated MNPs (Fe 3 O 4 @ L ‐arginine) were prepared by chemical coprecipitation of FeCl 3 ·6H 2 O and FeCl 2 ·4H 2 O salt solutions in the presence of L ‐arginine and used for this reaction …”

Cobalt (II) Complexes with Schiff Base Ligands Derived from Terephthalaldehyde and ortho-Substituted Anilines: Synthesis, Characterization and Antibacterial Activity

“…It has been revealed that Schiff bases play an important role by serving as chelating ligands in the main groups and transition metal coordination chemistry; owing to their stability in different oxidative and reductive conditions [9]. The interaction of these donor ligands and metal ions gives complexes of different geometries and literature survey reveals that these complexes are potentially more biologically active compounds [10] such as anticancer, antifungal, antibacterial, antimalarial, anti-inflammatory, antiviral, and antipyretic properties [11][12][13][14]. It should be noted that metal chelation can tremendously influence the antimicrobial/bioactive behavior of the organic ligands; therefore, the synthesis of various transition metal complexes has been attempted in this field [15].…”

Synthesis, Characterization and Biological evaluation of Co (II) complex of 1-(2,4-dihydroxyphenyl) ethanone Semicarbazone

“…The chelating properties of semicarbazone are due to ONO donor sequence and possess pharmaceutical activity. Electron rich hydrazine N atom is involved in the complex formation with metal ion with interesting medical and nonmedical properties and very popular in last decade 1,2 . [ Transition complexes of Schiff base ligands has important role in inorganic, metallo-organic and biochemistry 3,4 They have diverse, chemical, optical and magnetic properties by modifying with different ligands 5-7, the interaction of these donor ligands and metal ions gives complexes of different geometries and literature survey reveals that these complexes are biologically active such as anticancer, antifungal, antibacterial, antimalarial, antiviral, antipyretic properties [8][9][10] cobalt complexes with different Schiff bases showed antibacterial and antifungal activities [11][12][13] several compounds [14][15][16][17] are known to react with the metal ions to give coloured complexes and have been employed for development for quantitative extraction and spectrophotometric determination of metals at trace levels [18][19][20] . The interaction of transition metal ions with biologically active ligands is a subject of interest.…”