Total syntheses of the reported structures of piperolein B, isopiperolein B and piperamide C9:1(8E) have been achieved. The analytical data reported for piperolein B and piperamide C9:1(8E) match the synthetic values, however those for isopiperolein B do not. The cytotoxicities of these three structurally similar compounds against cancer cell lines of different tissue origins were evaluated and the results indicated that these compounds show differential effects on cancer cell viability.