Design, synthesis and biological potential of some isoxazole and hydroxypyrimidine derivatives containing pyrido [2,3-d] pyrimidine nucleus via chalcone series

Synthesis of 4-(2,4-dimethoxy-6-(5-substitutedphenylisoxazol-3-yl) pyrido[2,3-d] pyrimidin-7-yl)morpholine has been carried out by reaction of (E)-3-(2,4-dimethoxy-7-morpholinopyrido[2,3-d]pyrimidin-6-yl)-1-substituted phenylprop-2-en-1-one with hydroxylamine hydrochloride analogue to get the compounds 8a-f and synthesis of 4-(2,4-dimethoxy-7-morpholinopyrido[2,3-d]pyrimidin-6-yl)-6-phenylpyrimidin-2-ol with urea to get various hydroxypyrimidine of the studied analogue to get the compounds 9a-f. Structures of all the newly synthesized compounds have been characterized by instrumental method. Representative compounds of the synthesized product series have been tested and evaluated as antimicrobial agents.