11C labelling of AG957 -: a potential tyrphostin radiotracer for PET

Carbon-11 labelled 4-(N-2,5-dihydroxybenzyl)amino methyl benzoate (AG957), a potential radiotracer for imaging ber-abl receptors was synthesized. [C-11]AG957 was prepared by labelling 4-aminobenzoic acid using [C-11]CH3I, which affords the corresponding [C-11] methyl ester in excellent yields. Subsequent condensation of the amino group with 2,5-dihydroxybenzaldehyde formed the respective Schiff base. Reduction of this compound with NaBH3CN gave [C-11]AG957 in overall decay corrected radiochemical yield of 65-75% (based on (CH3I)-C-11) with an average specific radioactivity of 40 GBq/mumol (1.1 Ci/mumol). The total synthesis time from EOB including formulation was 45 min. At physiological pH, the compound was found to be sufficiently stable for in vitro and in vivo investigations. Copyright (C) 2002 John Wiley Sons, Ltd.