Abstract: This is a new precursor and new method for the synthesis of no-carrier-added O-(2-[18F]fluoroethyl)-L-Tyrosine which has been proved a suitable PET (position emission tomography) probe for tumor diagnosis imaging, the preparation of the title compound starts from precursors with the chemical structures as in Formula 1, wherein R1 is a protective group for the carboxyl functional group, R2 is a protective group for the amino group, and R3 acts as a leaving group. R1 represents an arylalkyl group, R2 represents a carboxyl group, and R3 represents a p-tosyloxy, methane sulfonyloxy or trifluoromethane sulfonyloxy or bromine, the invention includes a method for the syntheses of new precursors with the chemical structures as in Formula 1.

Abstract: This is a novel method for production of no-carrier-added O-(2-[18F]fluoroethyl)-L-Tyrosine, which has been proved a suitable PET (position emission tomography) probe for tumor diagnosis imaging, and the preparation of the title compound starts from precursors with the chemical structures as in Formula 1, wherein R1 is a protective group for the carboxyl functional group, R2 is a protective group for the amino group, and R3 acts as a leaving group, R1 represents an arylalkyl group, R2 represents a carboxyl group, and R3 represents a p-tosyloxy, methane sulfonyloxy or trifluoromethane sulfonyloxy or bromine, and the final purification of the product is using a separation column, which is very convenient for automated synthesis, and the invention uses the precursor with the chemical structures as in Formula 1.