Concise synthesis of tetrahydro derivatives of the pyrido[2,3-b]acridine and pyrido[3,2-b]acridine ring systems

✍ Scribed by Madel Mar Blanco; Carmen Avendaño; J.Carlos Menéndez

• Book ID: 104209642
• Publisher: Elsevier Science
• Year: 1999
• Tongue: French
• Weight: 589 KB
• Volume: 55
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(99)00738-3

✦ Synopsis

5,6,7,8-Tetrahydro-1,4-acridinequinones were readily prepared by Friedl~inder reaction between cyclohexanone and 2-amino-3,6-dimethoxybenzaldehydes or 2-amino-3,6-dimethoxyacetophenones, followed by oxidative demethylation. Their Diels-Alder reactions with l-dimethylamino-l-azadienes gave pyrido [3,2-b]acridines in a regioselective fashion. The regiochemistry of the cycloaddition could be inverted through the introduction of a bromine atom at the C-5 position, to give pyrido[2,3-b]acridines. The latter ring system is a structural fragment common to several polyciclic marine natural products with antitumour properties, including ascididemin, eilatin and biemnadin.