Heterocycles [c]-Fused onto Indoloquinoxaline. Synthesis of Novel Pyrano[2’,3’:4,5]indolo[2,3-b]quinoxalin-2-ones

Autor: Mustafa M. El-Abadelah, Almeqdad Y. Habashneh, Mohammed M. Abadleh, Wolfgang Voelter
Rok vydání: 2012
Předmět:
Zdroj: Zeitschrift für Naturforschung B. 67:725-730
ISSN: 1865-7117
0932-0776
DOI: 10.5560/znb.2012-0131
Popis: A synthesis of 4-methylpyrano[2,3-e]indole-2,8,9-trione (5) is achieved from 7-amino-4- methylcoumarin by adopting the classical Sandmeyer methodology. The cyclocondensation reaction of pyrano-isatin 5 with the appropriately substituted o-phenylenediamines 6 in polyphosphoric acid proceeded regioselectively to furnish the respective pyrano[2’,3’:4,5]indolo[2,3-b]quinoxalines 7a - c. Structural assignments of the new compounds are based on microanalytical and spectral (IR, MS and NMR) data.
Databáze: OpenAIRE