Synthesis and evaluation of an F-18 analog of forskolin for imaging adenylyl cyclase

We prepared two fluorine containing carbamate analogs of forskolin as poten tial agents for imaging adenylyl cyclase in the Living brain with positron emission tomography. Both compounds display high in vitro affinity for aden ylyl cyclase. The radiosynthesis of 7-(2-[F-18] fluoroethyl) carbamoyl fors kolin from an imidazolyl carbamate utilizes [F-18] fluoroethyl amine, prepa red by a novel method employing rapid deprotection and requiring no distill ation. The brain uptake in rats and monkeys of 7-(2-[F-18] fluoroethyl) car bamoyl forskolin is too low to be an effective imaging agent for this secon d messenger system. (C) 2000 Elsevier Science S.A. All rights reserved.