Specificity of the cyclization of 1-alkyl(aryl)sulfonylamino-9,10- anthraquinones into naphtho[1,2,3-cd]indol-6(2H)-ones

Article abstract of DOI:10.1134/S1070428008100187

Cyclization of N-(9,10-dioxo-9,10-dihydroanthracen-1-yl)methanesulfonamides to 2,6-dihydronaphtho[1,2,3-cd]indol-6-ones in DMSO-KOH involves intermediate formation of 2,3-dihydroanthra[1,9-cd]-[1λ⁶,2]thiazin-7-one 2,2-dioxides, whereas heterocy