Comparison of pharmacophore cinnoline and quinoline systems on the basis of computer calculation and pharmacological screening of their condensed systems

A series of new pyrimido[5,4-c]quinoline derivatives were prepared to compa re the pharmacophore systems of cinnoline and quinoline. These compounds we re obtained by the cyclocondensation of appropriately substituted 4-amino-3 -quinolinecarboxylic acids 3 with acetic anhydride to the respective 2methy l-1,3 -oxazino [5,4-c]quinolin-4(3 H)-ones 4. These derivatives reacted wit h amines and gave N-3 substituted 2-methylpyrimido[5,4-c]quinolin-4(3 H)-on es 6. 4-Amino-3-quinolinecarboxamide 2 reacted with diethyl carbonate to gi ve 1,2,3,4-tetrahydropyrimido[5,4-c]quinolin-2,4-diones 5. The SAR paramete rs of the derivatives obtained were analysed with the HyperChem 5.1/ChemPlu s 2.0 computer program. The compounds synthesized were screened for their e ffect on the CNS.