Revised Abstract A series of novel bi-thiazoles was synthesized by reaction of 2-(1-(2-(2-(1-(4-fluorophenyl)ethylidene)hydrazinyl)-4-methylthiazol-5-yl)ethylidene) hydrazine-1-carbothioamide 3 with a variety of hydrazonoyl chloride derivatives 4a-d, and 7 a-d affording 6a-d and 9a-d respectively in dioxane in the presence of triethyl amine as a base. Also, hydrazine-1-carbothioamide 3 reacts with substituted phenacyl bromide derivatives 10 a-d yielding 12a-d in appropriate reaction conditions. The mechanisms of the titled reactions were discussed. Structural assignments were based on spectroscopic methods (NMR, FTIR, MS). The new compounds were tested in vitro for their were subjected to in vitro anticancer screening against human hepatocellular carcinoma (HCT-116), (HepG-2) and the results showed that compounds 6a, 6d, 9a, 9c and 12a have promising activities compared with cisplatin reference drug.