S. Markey, K. Powers, D. Dubinsky
1980
Citations
1
Influential Citations
16
Citations
Journal
Journal of Labelled Compounds and Radiopharmaceuticals
Abstract
Two general schemes for the synthesis of isotope labelled monomethyl catecholamine metabolites are described. Catechol was converted to 2-methoxy-d3-phenol (2) with deuteromethyl iodide and reacted with sodium glyoxylate to form 4-hydroxy-3-methoxy-d3-mandelic acid (3). Hydrogenolysis of the methyl ester-diacetate of 3 with excess sodium borohydride in water yielded 4-hydroxy-3-methoxy-d3-phenylacetic acid (4). Reduction of 3 with diborane produced 4-hydroxy-3-methoxy-d3-phenylethylene glycol (5). An alternative route was to alkylate 3,4-dihydroxybenzaldehyde (6) and produce 3 or its 3-hydroxy-4-methoxy isomer via the nitrile mandelic acid synthesis. Suitability of these isotopic and isomeric variants as internal standards for quantitation by gas chromatography-mass spectrometry is discussed.