Synthesis of 8-[F-18]fluoroguanine derivatives: In vivo probes for imaginggene expression with positron emission tomography

A new method for the preparation of 8-[F-18]fluoroguanine derivatives based on a direct radiofluorination reaction has been developed. The radiofluori nation of ganciclovir (1a) with [F-18]F-2 was carried out in absolute ethan ol in the presence of tetraethylammonium hydroxide at room temperature to g ive 8-[F-18]fluoroganciclovir (3a) in an approximately 1% radiochemical yie ld. Similarly, 8-[F-18]fluoropenciclovir (3b), 8-[F-18]fluoroacyclovir (3c) , and 8-[F-18]fluoroguanosine (3d) were synthesized from penciclovir (1b), acyclovir (1c), and guanosine (1d), respectively, using [F-18]F-2. The stru ctural analyses of the final products (3a, 3b, 3c, and 3d) were carried out after F-18 decay by H-1, C-13, and F-18 nuclear magnetic resonance and hig h resolution mass spectroscopy. NUCL MED BIOL 27;2:157-162, 2000. (C) 2000 Elsevier Science Inc. All rights reserved.