title: Regioselective substitution of 6,7-dichloroquinoline-5,8-dione: synthesis and X-ray crystal structure of 4a,10,11-triazabenzo[3,2-a]fluorene-5,6-diones.
abstract: 6,7-Dichloroquinoline-5,8-dione (1) was reacted with a number of 2-aminopyridine derivatives. Of the several possible products of this reaction, 4a,10,11-triazabenzo[3,2-a]fluorene-5,6-dione (6), produced by condensation and rearrangement, was obtained as the major product, and its structure was subsequently unambigously determined by X-ray crystallographic study. Ortho-quinones were produced via nucleophilic substitution at position C7, which was unexpected, considering that para-quinones were produced via C6 substitution in the reaction between compound 1 and ethyl acetoacetate in our previous work. Such unexpected nucleophilic substitution at C7 provides an effective, yet simple route, to the preparation of biologically active ortho-quinone derivatives.
authors.affiliation: Division of Medicinal Chemistry, College of Pharmacy, Ewha Womans University, 11-1 Daehyun-dong, Seodaemun-ku, Seoul 120-750, South Korea.
authors.forename: Young-Shin
authors.initials: YS
authors.lastname: Kim
authors.forename: So-Young
authors.initials: SY
authors.lastname: Park
authors.forename: Myung-Eun
authors.initials: ME
authors.lastname: Suh
authors.forename: Hyun-Jung
authors.initials: HJ
authors.lastname: Lee
authors.forename: Dieter
authors.initials: D
authors.lastname: Schollmeyer
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology; D018360:Crystallography, X-Ray; D004317:Doxorubicin / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D005449:Fluorenes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D011804:Quinolines / Q000737:chemistry*; D011809:Quinones / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D013237:Stereoisomerism; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D005449:Fluorenes; D011804:Quinolines; D011809:Quinones; C058513:6,7-dichloroquinoline-5,8-dione; D004317:Doxorubicin