The reaction of 6-substituted 4-pyrone-2-carboxylic acids with o-phenylenediamine. Synthesis and structure of 3-(1H-1,5-benzodiazepin-2(3Н)-ylidenemethyl)quinoxalin-2(1H)-ones

Diastereoselective Synthesis of 2‐(1,3‐Dioxolanes‐4‐yl)‐4H‐pyran‐4‐ones from 2‐Diazo‐3,5‐dioxo‐6‐ynoates (sulfones) and Aldehydes Based on Tandem Cyclization‐Cycloaddition Strategy

“…γ‐Pyranone unit as a key structural motif exists in large numbers of drug molecules, natural products and synthetic biological molecules (Figure ) In addition, this type of compound has been widely used in organic synthesis . 1,3‐Dioxolanes also possess biological activity, and has been employed as inhibitors (Figure ) .…”

2-Aryl-6-Polyfluoroalkyl-4-Pyrones as Promising RF-Building-Blocks: Synthesis and Application for Construction of Fluorinated Azaheterocycles

“…Mainly, pyrones are of interest as useful and versatile building-blocks for the synthesis of valuable molecules [ 6 , 7 , 8 , 9 ], including pharmaceuticals [ 10 ] and pyranic fluorophores [ 11 ]. Pyrones as polyelectrophilic substrates and cyclic enone are able to react regioselectively with nucleophiles to undergo ring-opening transformations affording azaheterocycles [ 12 , 13 , 14 , 15 , 16 ]. The formation of the product is usually very sensitive to the reaction conditions (acidity, solvent polarity, temperature) that allows divergent syntheses on the basis of 4-pyrones [ 15 , 16 ].…”

“…To date considerable attention has been focused on 4-pyrones bearing the electron-withdrawing R F group, which demonstrate higher reactivity with high chemoselectivity of processes compared to non-fluorinated analogs [ 17 , 18 ]. The ring-opening reactions of 2-R F -4-pyrones can be applied for the preparation of a wide range of trifluoromethylated azaheterocycles, such as indoles, regioisomeric pyrazoles, pyridines, benzodiazepines etc., [ 14 , 16 , 17 , 18 ].…”