Synthesis of benz[b]acridine-6,11,12-triones
Abstract
Condensation of 2-Iithio-1-methyl-4-quinolone with methyl 2-(chloroformyl)benzoate gives 5-methylbenz[b]acridine-6,11–12-trione 3; addition of the anion of methyl 2-(1,3-dithian-2-yl)benzoate to 1-methoxycarbonyl-4-quinolone gives 5,5a-dihydro-11-hydroxy-5-methoxycarbonyl-12-oxaspiro{benz[b]acridine-6,2′(1′,3′-dithiane)}7.