Peldesine is an effective, competitive, reversible, and orally active inhibitor of purine nucleoside phosphorylase.

FMRF is a peptide consisting of 4 amino acid residues.

Methylsuccinic acid is a normal metabolite found in human fluids. Increased urinary levels of Methylsuccinic acid (together with ethylmalonic acid) are the main biochemical measurable features in ethylmalonic encephalopathy a rare metabolic disorder with an autosomal recessive mode of inheritance that is clinically characterized by neuromotor delay hyperlactic acidemia recurrent petechiae orthostatic acrocyanosis and chronic diarrhea.