A New Series of N-[2-(10H-Phenothiazinyl) Ethyl]-2-(Substituted Phenyl)-4-Oxo-5-[(Substituted Phenyl) Methylidene]-1-Iminothiazolidine, Compounds 5(A-M)Have Been Synthesized. By Microwave Method. the Cycloaddition Reaction of Thioglycolic Acid With N-[2-(10Hphenothiazinyl) Ethyl]-N’-[(Phenyl)Methylidene]-Hydrazine, Compounds 3(A-M) In the Presence of Anhydrous Zncl2 Afforded New Heterocyclic Compounds N-[2-(10Hphenothiazinyl) Ethyl]-2-(Phenyl)-4-Oxo-1-Iminothiazolidine, Compounds 4(A-M). the Later Product on Treatment With Several Selected Substituted Aromatic Aldehydes In the Presence of C2h5ona Undergoes Knoevenagel Reaction to Yield, Compounds 5(A-M). the Structure of Compounds 1, 2, 3(A-M), 4(A-M) and 5(A-M) Were Confirmed By Ir, 1H Nmr, 13C Nmr, Fab-Mass and Chemical Analysis. Compounds 5(A-M) Have Been Screened For Their Antimicrobial and Ant Tubercular Activities, Displayed Satisfactory Results.