Multicomponent reactions (MCR's) have enabled the rapid chemical synthesis of complex and diverse molecular scaffolds, and this has, in turn, accelerated the discovery of small molecules with therapeutic potential . The Biginelli cyclocondensation is a three-component acid-catalyzed MCR between an aldehyde, ß-ketoester, and urea, which has been used to produce dihydropyrimidinone and tetrahydropyrimidinone heterocycles . One such dihydropyrimidinone, monastrol , was found to be a potent inhibitor of kinesin Eg5, a motor protein necessary for the assembly of mitotic spindle fibers, thereby inducing apoptosis by preventing the development of spindle bipolarity and arresting cells in mitosis . This discovery has inspired the synthesis of other antiproliferative dihydropyrimidinone scaffolds, including LaSOM-63 (2), which unlike monastrol, induces apoptosis of glioma cells through inhibition of ecto-5'nucleotidase/CD73 activity . The broad biological applicability of these scaffolds accessed through the Biginelli cyclocondensation highlights the utility of this MCR as a synthetic platform for the discovery of bioactive small molecules.