This work including sythesis heterocyclic compounds such as Oxazin , Thiazin , Oxazepin and Chalcone derivatives during cyclization of these compounds by Urea and Thiurea.all these derivatives were synthesized and identified by FT-IR , 1H- NMR spectra and elemental analysis C.H.N.S as well as study of biological activity with four types of bacteria Gram- positive and Gram- negative ,this study exhibited high biological activity for all these compounds . Nadia