合成路线1

The [18F]-labeled compound is prepared as follows. Benzyloxy acetone (I) is treated with KCN and buffered (NH4)2CO3 to produce hydantoin (II). Alkaline hydrolysis of (II), followed by treatment of the crude aminoacid (III) with Boc2O gives the Boc-protected aminoacid (IV). The esterification of (IV) by means of t-butyl trichlroacetimidate affords the t-butyl ester (V), which is N-methylated with MeI and NaH to give compound (VI). Catalytic hydrogenolysis of the benzyl ether group of (VI) yields alcohol (VII). Selective removal of the N-Boc group of (VII) in the presence of the t-butyl ester to furnish (VIII) is achieved with p-toluenesulfonic acid in hot ethanol. Reaction of amino alcohol (VIII) with SOCl2 produces the cyclic sulfamidite (IX), which is further oxidized to sulfamidate (X) with NaIO4 in the presence of a catalytic amount of RuO2. The radiolabeled aminoacid is then obtained by treatment of (X) with [18F]-fluoride, followed by acidic cleavage of the t-butyl ester group.