Synthesis and structure-activity relationship studies of substituted isoquinoline analogs as antitumor agent

A number of substituted isoquinolin-1-ones, possible bioisosteres of the 5-aryl substituted 2,3-dihydroimidazo[2,1-a]isoquinolines, were synthesized and tested for their antitumor activity against five different human tumor cell lines. O-(3-hydroxypropyl) substituted compound (15) exhibited the best antitumor activity which is 3-5 times better than 5-[4'-(piperidinomethyl) phenyl]-2,3-dihydroimidazo[2,1-a]isoquinoline (1).