Synthesis and Use of Deuterated 3,4-Dihydroxyphenylglycolaldehyde as an Internal Standard for Determination of Dopegal in Brain Tissue by Gas Chromatography–Mass Spectrometry

Trideuterated 3,4-dihydroxyphenylglycolaldehyde (DOPEGAL-d3) was synthesized from tetradeuterated catechol. After derivatization withN-methyl-N-trimethylsilyltrifluoroacetamide, the identity of DOPEGAL-d3was confirmed by comparison with unlabeled DOPEGAL by gas chromatography–mass spectrometry (GC–MS); they have the same pattern of mass fragmentation. The deuterated DOPEGAL was used as an internal standard for the determination of DOPEGAL in human locus ceruleus by GC–MS in the selected-ion-monitoring mode.