Synthesis of acronycine isosters

A One‐Pot Synthesis of Pyranocoumarins Through Microwave‐Promoted Propargyl Claisen Rearrangement/Wittig Olefination

“…Recent syntheses of pyranocoumarins, inter alia seselin (8), involve catalyst-free multicomponent [29] or two-step condensation reactions [28] that start from phloroglucinol, ring-closing metathesis reactions at preformed coumarin scaffolds, [30] cobalt-catalyzed cyclizative carbonylations of vinylphenols, [31] cyclizative Wittig olefinations of 6-formyl chromenes, [32] or oxidative selenium-mediated cyclizations of prenylated hydroxycoumarins. [33] Most syntheses of seselin and structurally related angular pyranocoumarins are prepared from preformed coumarins, either by thermal propargyl Claisen rearrangements of the corresponding coumarin 2,2-dimethylpropargyl ethers [34,35] or by acid-catalyzed condensations of hydroxycoumarins and acetals of senecialdehyde. [36] Microwave conditions have been used only in a limited number of pyranocoumarin syntheses.…”

Formylnitroenamines: useful building blocks for nitrated pyridones and aminopyridines with functional groups

“…11 Much attention has been also paid to 2-pyridones having a carbonyl group at the 3-position as building blocks for synthesizing potassium channel activators 12 and antitumor agents such as camptothecin derivatives 13 and acronycine. 14 Meanwhile, pyridones having both a nitro and a carbonyl group have been shown to be applicable to medicines for ischemic heart diseases and hypertension, 15 and to the synthetic intermediates for inhibitors against receptors for aamino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) 16 and the 3-phosphoinositide-dependent protein kinase-1 (PDK1). 17 In view of the above aspects, pyridones having both a nitro and a carbonyl group are expected to serve as useful precursors of biologically active materials such as medicines and agricultural chemicals.…”

Biosynthesis of acridone alkaloids formation of rutacridone by cell‐free extracts of Ruta graveolens cell suspension cultures

“…The anthranilic acid-derived acridones and furoquinolines occur frequently concomitantly in various rutaceous species. A number of furoacridones including rutacridone (7) has been found in Ruta graveolens L. Their possible biosynthetic relationship was recently discussed [1].…”