Potential antitumor agents. 1. Analogs of camptothecin

Abstract

All compds were analyzed for N. 6 In KBr pellets. The ir spectra of 131 aromatic Schiff bases exhibit absorption at 1613-1631) cm 1 in solid KBr and 1618-1645 cm 1 in CHC13.

Synthesis of New Hydroxybenzo[a]carbazoles

“…)-dione (1) and 4-hydroxy-7-methoxy-2-methylbenzo[a]pyrrolo [3,4-c]carbazole-1,3(2H,8H)dione (2) were obtained by reaction of diphenol C with 4-5 equivalents of benzyl bromide or methyl iodide in the presence of potassium carbonate (Scheme 1). Diphenol C was synthesized from indolylmaleimide A via a Diels-Alder cycloaddition/oxidation with 1,4-benzoquinone followed by reduction using sodium dithionite.…”

“…A number of biologically active compounds possess a benzo[a]carbazole framework. According to their substituents, these compounds can exhibit antifungal and antitumor activities, [1][2][3][4] antiestrogenic properties, 5 or kinase inhibitory activities. [6][7][8] Various approaches have been reported for the synthesis of benzo[a]carbazoles including photocyclization, palladium-catalyzed cross-coupling reactions, Fischer indolization, Diels-Alder reactions, and irradiation of a benzotriazole derivative.…”

Camptothecin

“…In a separate study, several model compounds (CLXXXII-CLXXXV) were synthesized through the indole-quinolone conversion of the corresponding indole derivatives (58). In a separate study, several model compounds (CLXXXII-CLXXXV) were synthesized through the indole-quinolone conversion of the corresponding indole derivatives (58).…”

“…One more indole compound, which was recently synthesized as a potential intermediate to camptothecin, is the hemiketal CLXXXI (57). In a separate study, several model compounds (CLXXXII-CLXXXV) were synthesized through the indole-quinolone conversion of the corresponding indole derivatives (58). (1,61).…”

Substituted Benzo[a]carbazoles and Indoleacetic Acids from Arylglyoxals and Enamines through Domino Condensation, Thermal Cyclization, and Aromatization

“…Among various carbazole derivatives, the aryl‐ and heteroaryl‐annulated[ a ]carbazoles have drawn significant biological and pharmacological interest that has ensued from their affinity toward nucleic acids 3. Particularly, the benzo[ a ]carbazole frameworks may exhibit antitumor activity,4a antiestrogenic properties4b or kinase inhibitory activities 4c. Hence, these are appealing targets for organic chemists.…”