Photocyclisations of some 3‐alkoxy‐2‐thienylchromones

Abstract

Photoreorganisations of some 3-allyloxy-2-thienylchromones have been described. The photoreactions are initiated through the intramolecular H-abstraction to provide angular tetracyclic compounds. These chromones yield good chemical efficiency due to the involvement of highly stabilized allylic 1,4-biradicals.

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).…”