3-Acetylcoumarin (1) was utilized as a key intermediate for the synthesis of 2-aminothiazole derivative 3 via bromination of 1 followed by treatment of the formed acetylbromide 2 with thiourea or via Bignailli reaction of 1. Treatment of 3 with 2 afforded the bis-coumarin 4, whereas, cyanoacetylation of 3 followed by treatment of the formed cyanoacetamide 6 with salicyaldehyde give the bis-coumarin 7. Reaction of 6 with phenyl isothiocyanate in DMF/KOH produced the potassium salt 8, which cyclized with chloroacetyl chloride to give the thiazolidinone 9. Acidification of 8 with HCl afforded the thiocarbamoyl 10, which condensed with 2 in DMF to give the mercapto derivative 12, whereas in DMF/TEA gave the thiophene derivative 13. The thiophenes 15a–c were achieved via treatment of the thiocarbamoyls 14a–c with 2 in DMF/TEA, whereas, in DMF gave the corresponding thiazoles 16a–c. Treatment of the components 17a, b with carbon disulfide in DMF/KOH followed by addition of 2 afforded the dithioacetals 19a, b. Cyclization of 19b under alkaline condition gave the desired thiophene 20. Representative compounds of the synthesized products were evaluated as antitumor and antioxidant agents.