In this study heterocyclic compounds were prepared from thioxanthone derivatives and determined their structure by measuring melting point (M.P) and infrared spectrum (FTR) and 1HNMR for each one. These derivatives used for testing antibacterial activity Streptococcus mutans, Staphylococcus saprophyticus, Enterococcus faecalis (Gram positive bacteria) Haemophilus influenzae (Gram negative bacteria). Prepared compounds I,II,III,IIV showed clear antibacterial activity against all tested bacteria either as solutions or powder. Solutions with DMSO have antibacterial activity greater than those with distilled. Compound I showed greater antibacterial activity than other compounds. On the other hand, Gram-positive bacteria showed higher sensitivity than Gram-negative ones to all solutions. The results of thermal analysis of the prepared derivatives showed stability at high temperatures (DSC and TG curves). Key words: Thioxanthone, Schiff bases, antibacterial activity , imidazolidin-4-one , Oxazepine .

In the 1,3-dipolar cycloaddition, a 1,3-dipole and a dipolarophile interact chemically to produce a five-membered ring. The Huisgen cycloaddition occurs when an organic azide and an alkyne unite to form a 1,3-dipolar cycloaddition that results in a 1,2,3-triazole. 1,3-dipolar cycloaddition is an essential step in the regio- and stereoselective synthesis of five-membered heterocycles and their ring-opened acyclic derivatives. Some of the cycloadducts produced by these reactions were converted into enantiopure precursors known to exist in some biologically active chemicals as well as an active stereoisomer of a pine sawfly sex pheromone. The synthesis of several new enantiopure organocatalysts that were shown to be helpful in some The synthetic utility of these 1,3-dipolar cycloaddition processes with nitrones and a,b-unsaturated aldehydes was further demonstrated. There are times when these reactions have modest to moderate diastereofacial selectivity. the choose actual and nonracemic have improved. Compound collections are created in chemical biology research using the BIOS concept, which draws its inspiration from natural product scaffolds. In BIOS, the primary criterion utilized to develop hypotheses for the design and synthesis of targeted chemical libraries is biological relevance. Because they outline the chemical domains that nature has explored, the underlying scaffolds of natural product classes in particular serve as an inspiration for BIOS because they can be thought of as "trivet can often be achieved if both the azomethine ylide and the dipolarophile are chi privileged