An efficient green synthesis and antibacterial activity of 1,3‐benzoxazine and 1,3‐naphthoxazine using NaCl.SiO₂ as solid catalyst in neat condition

Abstract

A series of 1,3‐oxazine derivatives were synthesized by a one‐pot three‐component (ie, phenol, formaldehyde, amine) method where SiO2 bonded with NaCl was used as a reusable, more efficient, easily prepared, and available solid catalyst. The reactions were also carried out at room temperature for greener approach. in vitro studies for the synthesized compounds were also done against two gram‐positive (Bacillus subtilis and Staphylococcus aureus) and two gram‐negative bacteria (Escherichia coli and Klebsiella pneumonia) to check for their applicability as an antibacterial agent where some of the synthesized compounds gives the best antibacterial activity against selected bacterial strains. Streptomycin was used as a standard control for all the microbial test.

1,3‐Oxazine as a Promising Scaffold for the Development of Biologically Active Lead Molecules

“…In vitro antibacterial studies of synthesized compounds against two Gram + ve (Bacillus subtilis and Staphylococcus aureus) and two Gram À ve (E. coli and Klebsiella pneumonia) bacteria where many compounds showed potent antibacterial activity showed that compound 65 (Figure 10) exhibited maximum inhibition against all the bacterial strains with MIC of 0.023 for B. subtilis, E. coli and S. aureus and 0.005 for K. pneumonia. [44] Piste et al in 2018 reported the synthesis of 3-(4-chlorophenyl)-4-methylidene-4,8-dihydro-2H,5H-1,3-oxazine-2,5,7(3H)- trione derivatives. 5-acetyl-4-hydroxy-2H-1,3-thiazine-2,6(3H)-dione and different substituted amine were reacted in the presence of catalytic amount of glacial acetic acid under reflux condition to give intermediate compounds that underwent cyclization in presence of phosgene to give oxazine derivatives.…”

“…in 2020 synthesized a novel series of 1,3‐oxazine analogs by one‐pot three component method in which amine, formaldehyde and phenol were reacted in presence of silica bonded sodium chloride, a more efficient, reusable, easily available and prepared solid catalyst. In vitro antibacterial studies of synthesized compounds against two Gram +ve ( Bacillus subtilis and Staphylococcus aureus ) and two Gram −ve ( E. coli and Klebsiella pneumonia ) bacteria where many compounds showed potent antibacterial activity showed that compound 65 (Figure 10) exhibited maximum inhibition against all the bacterial strains with MIC of 0.023 for B. subtilis , E. coli and S. aureus and 0.005 for K. pneumonia [44] …”

Synthesis and Antimicrobial Activity of Novel Bisbenzoxazine Monomer

“…The Benzoxazine nucleus has been known to exhibit significant antimicrobial activity against both bacteria and fungi. Given that the newly synthesized SA-HMDA-BZ also contains the same Benzoxazine nucleus, we conducted antimicrobial activity tests to determine whether it retains the same potent antimicrobial properties as its predecessor [10][11][12][13][14]. Aminomethyl derivatives of benzoxazine have shown potential for use as anticancer, antibacterial, analgesic, and anti-inflammatory agents [15][16][17].…”