Innovative multiple heterocyclic rings incorporating phenothiazine moiety (2-16) were synthesized through the reaction of N-cyanoacetamide phenothiazine derivative (2) with various types of reagents. The new compounds were tested against their antimicrobial activity. Compounds 10, 14, 15 and 16 showed higher activity toward Gram (+) than Gram (-) bacteria strains. Spectral and analytical data confirmed the correct structures of all the compounds.