Regular paperThe identification of tiglylglycine in the urine of a child with β-methylcrotonylgeycinuria

A child with β-methylcrotonylglycinuria and β-hydroxyisovalericaciduria has been shown to excrete a large amount of a previously undescribed glycine conjugate. Mass spectrometry indicated that this conjugate might be an isomer of β-methylcrotonylglycine. Further analysis of the material after isolation and hydrogenation suggested that it was tiglylglycine. The identity of retention times and mass spectra of the methylesters of synthetic tiglylglycine and 2-methylbutyrylglycine with those of the abnormal metabolite and its hydrogenated derivative respectively supported this conclusion.