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Regio- and Stereoselective Synthesis of Deuterium-Labeled Glutamic Acids via a Tetramic Acid Derivative
1Department of Bioengineering, Tokai University, 4-1-1 Kitakaname, Hiratsuka, Kanagawa259-1292, Japan.
Abstract:
In this study, stereoselective deuterium labeling of the side chain of glutamic acid was investigated. Treatment of tetramic acid derived from d-serine and Meldrum's acid with sodium borohydride-d4 and/or acetic acid-d1, followed by formal dehydration, enabled the construction of a 3,4-didehydropyroglutaminol framework bearing deuterium labels at the olefin position. Further catalytic hydrogenation or deuteration of olefins ultimately enabled the synthesis of seven isotopomers of glutamic acid regio- and stereoselectively deuterated at the β- and γ-positions.
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