Synthesis and in vitro anti-bacterial evaluation of tetracyclic-ortho-fused 4H-naphtho[1',2'-5,6]pyrano[3,4-d](1,2,3)selenadiazole and its derivatives.

Synthesis of new heterocyclic compounds 3a-e containing naphthopyran and selenadiazole as the heterocyclic sub-units in the molecule is achieved using high yielding synthetic protocol. These molecules 3a-e have shown moderate anti-bacterial activity against some gram-positive and gram-negative bacterias.