Benzamide riboside [BR,(1-β-D-ribofuranosyl) benzene-3-carboxamide],a novel C-glycoside analogue of nicotinamide riboside,has been studied because of its excellent cytotoxic activity.BR is metabolized intracellularly in malignant cells to its active metabolite benzamide adenine dinucleotide (BAD),which inhibits the key enzyme of guanylate biosynthesis inosine 5-monophosphate dehydrogenase (IMPDH),resulting in the inhibition of cell proliferation.