More than 100 FDA-approved drugs contain the piperazine moiety. Piperazine-based analogues may advantageously alter important pharmacokinetic properties when grafted onto molecular scaffolds. In 2018, chemists showed that replacing a piperazine ring in the drug Olaparib with the spirodiamine analogue beneficially affected activity and reduced cytotoxicity of the parent compound. Herein we have designed and synthesized a library of piperazine analogues for drug design.