An asymmetric approach to the synthesis of a carbon-11 labelled gliotransmitter d-serine

Endogenous d-serine, a co-transmitter of glutamate for synaptic N-methyl-d-aspartate receptors, is implicated in an array of health conditions. The feasibility of a rapid asymmetric preparation of carbon-11 labelled gliotransmitter d-serine is demonstrated via the hydroxy-methylation of a chiral nickel(II) complex. Using an automated radiochemistry synthesiser the key intermediate was obtained with 80 % diastereomeric excess in a 1 min reaction. Further optimisation of the starting glycine synthon is possible in order to achieve even higher stereoselectivity of synthesis, which can benefit subsequent separation–deprotection of the diastereomeric intermediate.