ABSTRACT
In a one-pot synthesis pyrido[2,3-d] pyrimidine-2-thione derivatives [3a-c] were prepared via the reaction of a mixture of 6-aminothiouracil [1], cyclooctanone and a proper aldehyde in dimethylformamide. Compound 3 reacted with a mixture of chloroacetic acid and aromatic aldehyde in acetic acid and acetic anhydride to give 6-aryl-thiazolo [4,5-a] cyclooctenopyrido [2,3-d] pyrimidine -3,5-diones [4a-c]. Compound 3b underwent cyclization on boiling with 3-chloro-2,4-pentandione in acetic anhydride/pyridine solution to give 5. On the other hand, compound 3b reacted with bromo-malononitrile to give enaminonitrile [6] Compound 6 reacted also with aliphatic acids to give 14-[chlorophenyl]-2-[unsub./methyl] pyrimido[4',5':4,5] thia-zolo[3,2-a] cyclooctenopyrido [23-d] pyrimidine- 4,15- dione [8a,b]
Subject(s)
Thiazoles , Ketones , Anti-Inflammatory AgentsABSTRACT
6-aminothiouracil [1] reacts in boiling dimethylformamide with cyclic alpha, beta -unsaturated ketones [2] yielding the 7-aryl-thioxo 5, 6, 7, 10, 11, 12-hexahydro, 7-aryl-10-thioxo-5, 6, 10, 11-tetrahydro -9H-benzo [h] pyrimido [4, 5-b]quinolin-8-one systems[4, 5] and 5-aryl-2-thioxo-1, 2, 3, 5, 6, 7, 8, 9, 10, 11-decahydro-, 5-aryl-2-thioxo-1, 2, 3, 6, 7-, 8, 9, 10-octahydrocyclohepta [5, 6] pyride [2, 3-d] pyrimidin-4-one[8, 9], respectively. The latter pyridopyrimidines reacted with chloroacetic acid in presence of an aidehyde to furnish a 10- arylidene -7- aryl- 5, 6- dihydro-11- thia-8a, 12, 13- triazabenzo- [a] cyclopenta [i] anthracene- 8, 9- dione or 2 -arylidene -5- aryl- 7, 8, 9, 10- tetrahydro -6H-1-thia-3a, 11, 12-triaza-cyclohepta [b] cyclopenta [g] naphthalene -3, 4-dione [10, 11]. The reaction with halo-derivatives such as methyliodide, 3-chloro-2.4 pentanedione furnished the alkylated pyrimidines 12, 14, 16, 17, 19, 20. The latter products reacted with hydrazine hydrate to give the hydrazine derivatives 21. The cyclization of 12, 14 to 13, 15 using acetic anhydride/pyridine have been reported