10.22376/ijpbs.2019.10.1.p1-12 Volume 8 Issue 2 2017 (April - June) To synthesize some novel thiazolidinone bearing acridinone moiety by using various aromatic aldehydes. The newly synthesized compounds were screened for microbiological screening. A series of 5-arylidene-3-(2-phenyl-4-oxo-1,3-thiazolidine) acetohydrazido acridin-9-one have been synthesized via condensation of 3-(2-phenyl-4-oxo-1,3-thiazolidine) acetamido acridin-9-one with various aromatic aldehyde. These compounds confirmed by physical (TLC and M.P.) and spectral data (IR, NMR and MASS) and were subjected to microbiological screening viz antibacterial and antifungal activity. All the synthesized compounds proved to have potent antimicrobial activity against Gram positive, Gram negative and Fungal organism. PANKAJ BABOO AND S.K.GUPTA Thiazolidinone derivatives, Ullmann condensation, acridin-9(10H)-one, antimicrobial activity. 92-96