Photoinduced Synthesis of New Diisochromenochromen-4-ones and Their Antimicrobial Activities

Abstract

The diisochromenochromen-4-one 3a-3b, 4a-4c, 5a-6a & 7 have been prepared from the photocyclization reaction of bischromen-4-one 2a-2e. The later compounds are obtained from the O-alkylation of the suitable 3-hydroxy-2-aryl-4H-chromen-4-one 1a-1e with 4,4′-bischloromethyl-diphenyl in dry acetone, anhydrous K2CO3, and PTC (Bu4N+I−) under refluxing conditions. The structures of compounds 2a-2e, 3a-3b, 4a-4c, 5a-6a & 7 have been characterized from the rigorous analysis of their IR, 1H-NMR, 13C-NMR, ESI-Mass, and elemental analysis. The antibacterial and antifungal activities of the synthesized products were also evaluated against the Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Aspergillus janus and Penicillium glabrum, respectively. Some of the tested compounds showed significant activity against the above-said microorganisms.

Novel bisbenzopyronopyran derivatives: photochemical synthesis and their in‐vitro antimicrobial studies

“…With aforesaid literature knowledge in mind and by following our earlier results dealing with the photo-transformations of 3-alkoxychromones/bischrom ones, [40][41][42][43][44] now we wish to report herein the detailed F I G U R E 1 Examples of chromone based therapeutic drugs photochemical cyclization reactions of alkyl/aromatic/ heteroaromatic chain linked bischromones 3(a-h). The foremost objective of this study was to establish a straightforward photochemical protocol for the syntheses of novel bisbenzopyronopyrans (bis-isochromeno-chromenones) 4(a-h)/5(a-h).…”