PROTECTED TYROSINE DERIVATIVES, METHOD FOR THE PRODUCTION THEREOF AND USE OF THE SAME FOR PRODUCING O-(2- ?18 F]-FLUOROETHYL)-L-TYROSINE

摘要

Protected O-(2-substituted ethyl)-L-tyrosine derivatives (I) are new. L-Tyrosine derivatives of formula (I) are new. R1 = carboxy-protecting group; R2 = amino-protecting group; and R3 = leaving group. Independent claims are also included for the following: (1) preparation of (I); and (2) preparation of O-(2-(18F)-fluoroethyl)-L-tyrosine (A) comprising reacting (I) with a tetraalkylammonium (18F)-fluoride of formula N<+>(R4)4.<18>F or <18>F-(2,2,2)-kryptand, cleaving the protecting groups R1 and R2 from the product of formula (I; R3 replaced by <18>F) under acidic conditions and purifying the product. R4 = 3-6C alkyl, especially tert. butyl.