Synthesis of alkoxyphthalimide derivatives of p-bis-(2-hydroxy-4-aryl-6-iminothiazolidino[ 4,5-b ]pyrimidin-N6-yl)biphenyls

Synthetic Organic Chemistry Laboratory, Department of Chemistry, Mohanlal Sukhadia University, Udaipur-313 001, India E-mail : gtalesara@yahoo.com; bsyadav2000@rediffmail.com Manuscript received 5 May 2004, revised 1 November 2004, accepted 5 January 2005 Biphcnyl-yl-4,4' -bisthiourea 1 reacts with monochloroacetic acid in presence of anhydrous sodium acetate to furnish p-bis-(2-iminothiazolidin-4-one-N2 -yl)hiphenyl 2. Condensation of ω-hromoalkoxyphthalimides 3a-c with 2 gave corresponding alkoxyphthalimidc derivatives 4a-c. In the compounds 4a-c, reactive methylene group of thiazolidinone ring at position-5 was condensed with araldchydes 5a-c to give p-bis-(3-n-alkoxyphthalimido-5-arylidenc-2-iminothiazolidin-4-one-N2 -yl)biphenyls 6a-i. The titled compounds 7a-i were synthesized by cyclisation reaction of the compounds 6a-i with urea in the presence of anhydrous sodium acetate in acetic acid medium. In another reaction route, substituted benzaldehydes 5a-c were reacted first with 2 to give p-bis-(S-arylidene-2-iminothiazolidin-4-one-N2-yl)biphenyls 8a-c which could he cyclised with urea to furnish p-bis-(2-hydroxy-4-aryl-6-iminothiazolidino[4,5- b ]pyrimidin-N6-yllbiphenyls 9a-c. The compounds 6a-i and 7a-i were also synthesized by condensation reactions of 8a-c and 9a-c with 3a-c respectively