Design and Synthesis of New Series of 2-Oxo-2H-Selenopyrano[2,3-b]Quinoline-3-Carboxylates and Evaluation of Their Antibacterial Activity.

In the present work, newly designed ethyl 2-oxo-2H-selenopyrano[2, 3-b]quinoline-3-carboxylates (4a–4f) were synthesized by reaction of 3-formyl-2-selenoquinolines (3a–3f) with diethyl malonate in the presence of catalytic amounts of piperidine. The intermediate 3-formyl-2-selenoquinolines (3a–3f) were synthesized by the action of NaHSe on substituted 2-chloroquinoline-3-carbaldehydes (2a–2f). The new series of 2-chloroquinoline-3-carbaldehydes (2a–2f) were synthesized from the corresponding substituted acetanilides (1a–1f) using available literature methods. The structures of all synthesized compounds were characterized by elemental analysis, IR, 1H NMR, and mass spectroscopy data. Newly synthesized compounds were evaluated for their antibacterial properties and found to exhibit a wide spectrum of antibacterial activity. In particular, compounds 4d and 4e were highly active against S. aureus and M. roseus species. [ABSTRACT FROM AUTHOR]