Synthesis and Antimicrobial Activity of Benzo[H][1,6]Naphthyridine Derivatives

Raghunath BT, Balasaheb PP, Sa

Abstract

One pot organic reaction of 2-aminoquinoline 1 and ethyl orthoacetate with butynenitrile 2 yielded 4-amino butenenitrile quinoline 4 and with diethyl 2-(ethoxymethylene) malonate 5 yielded 4-amino methylene diethyl malonate 6 in good yield. The quinoline 6 was oxidized to quinolone 7 in acetic acid. The cyclization compound 6 was successfully attempted using Pb2O furnished 4-hydroxy benzo[h][1,6] naphthyride and on refluxing compound 6 in POCl3 yielded 4-chloro benzo[h][1,6] naphthyride derivatives 9. All new compounds showed good antimicrobial activity against standard ampicillin and streptomycin.