Aj. Allentoff et al., SYNTHESIS OF C-14-LABELED CGS-19755, A SELECTIVE NMDA ANTAGONIST, Journal of labelled compounds & radiopharmaceuticals, 38(11), 1996, pp. 989-998
Citations number
8
Categorie Soggetti
Chemistry Analytical","Pharmacology & Pharmacy","Biochemical Research Methods
CGS 19755 is a selective NMDA (N-methyl-D-aspartate) antagonist presen
tly under development as a neuronal protecting agent after stroke and
head trauma. It was synthesized with C-14-labelling in the carboxylic
acid side chain via the synthetic route displayed in Scheme 1. Key ste
ps in the synthesis involved a Reissert-Henze addition of potassium [C
-14]cyanide to a functionalized pyridine N-oxide, followed by hydrolys
is and a selective hydrogenation affording the desired cis-substituted
piperidine target. Using this procedure, [C-14]CGS 19755 was prepared
with radiochemical purity of 99.6%. The synthesis demonstrates the ut
ility of the Reissert-Henze reaction, in conjunction with palladium/rh
odium-catalyzed hydrogenation, as a facile means of preparing C-14-lab
elled cis-2,4-substituted cyclic amino acids.