N-(3-Phenylpropionyl)glycine is an acylglycine.¹Urinary levels of N-(3-phenylpropionyl)glycine are increased in patients with medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, an inborn error of metabolism characterized by intolerance to fasting, episodic vomiting, hypoketotic hypoglycemia, and dicarboxylic aciduria.

1.Rinaldo, P., O’Shea, J.J., Coates, P.M., et al.Medium-chain acyl-CoA dehydrogenase deficiency. Diagnosis by stable-isotope dilution measurement of urinary n-hexanoylglycine and 3-phenylpropionylglycineN. Engl. J. Med.319(20)1308-1313(1988)