The synthesis of angular heteroarenochromones based on 7-hydroxy-8-carbonylchromones

Abstract

The present review highlights advanced strategies to the synthesis of the chromones annulated with O-and N-containing heterocycles at C(7)-C(8) bond. Due to the prevalence of such motives in different kinds of natural flavonoids and some alkaloids, fused chromones have attracted a great deal of attention so far. On the other hand a wide range of biological activities is displayed by the compounds of this type both among naturally occurring flavonoids and their synthetic analogues. 8-Carbonyl-7-hydroxychromones proved to be versatile synthones for the synthesis of angular hetarenochromones via approach of annulation of a heterocycle to the chromone core. It also addresses the question of the biological activity of naturally occurring and fused synthetic hetarenochromones. ________________________________________________________________________________

Synthesis of linear hetarenochromones based on 7-hydroxy-6-formyl(acetyl)chromones

“…ortho-Hydroxyformyl(acetyl)chromones are treated as attractive starting materials for the synthesis of angular and linear hetarenochromones by the first route. The syntheses of angular hetarenochromones have been highlited in reviews [6,7].…”

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

“…[23] They are omnipresent in nature particularly in plants realm and usually found as the mother fragment in numerous flavonoids, that is, flavones, flavonols, and isoflavones. [24,25] They are also studied as pivotal intermediates in the generations of bioactive heterocyclic systems. These substrates have engrossed much attention in the field of synthetic chemistry due to their wide range of bioactivities.…”

Synthesis of chromones, annulated with oxygen-containing heterocycles with two hetero atoms at C(7)-C(8) bond

“…These are first and foremost furo [2,3-h]chromones and pyrano [2,3f]chromones. Their syntheses and biological activity have been highlited in reviews [1,2].…”

“…Their O,N-containing analogues remain unobserved among natural products. Chromones annulated with oxazole and oxazine cycles, namely 2-methylchromeno [7,8-d] [1,3]оxazol-6-оne, chromeno [7,8-d] [1,3]оxazol-2,6(3Н)dіоne, 4Н-chromeno [8,7-d] [1,2]оxazol-4-оne and 3,4-dihydrochromeno [8,7-b] [1,4]оxazin-7(2Н)-оne are described in the review [1].…”