In vivo quantification of 5-HT1A-[18F]MPPF interactions in rats using the YAP-(S)PET scanner and a beta-microprobe.

We performed full modeling analysis of 5-HT(1A)-[(18)F]MPPF interactions using the beta-microprobe (beta P) and a YAP-(S)PET scanner. Sixteen Wistar rats were used for beta P (n=5) and YAP-(S)PET (n=5) acquisitions and metabolite studies (n=6). Time-concentration curves were obtained in the hippocampus, raphe dorsalis, frontal cortex and cerebellum, using three injections of [(18)F]MPPF at different specific activities.

Fully automated [18F]fluorocholine synthesis in the TracerLab MX FDG Coincidence synthesizer.

Introduction: We developed a new fully automated method for the radiosynthesis of [18F]fluorocholine by modifying the commercial 2-[18F]fluoro-2-d-deoxy-glucose ([18F]FDG) synthesizer module (GE TracerLab MX, formerly Coincidence).

Methods: [18F]Flurocholine was synthesized by (18)F-fluoroalkylation of N,N-dimethylaminoethanol using [18F]fluorobromomethane as fluoromethylating agent. [18F]Fluorobromomethane was produced by reaction of dibromomethane with [18F]fluoride, assisted by Kryptofix 2.

Preparation of tertiary amides from carbamoyl chlorides and organocuprates.

[reaction: see text] Reaction of carbamoyl chlorides with cyano-Gilman cuprates affords tertiary amides in good to excellent yields. The reaction is general due to the possibility of using reagents made either from organolithium or from Grignard compounds. The characterization of the main side products allowed for the suggestion of a possible mechanism.

Studies toward labeling cytisine with [11C]phosgene: rapid synthesis of a delta-lactam involving a new chemoselective lithiation-annulation method.

With the aim of the radiolabeling of cytisine, a potent agonist of nicotinic receptors, with [(11)C]phosgene, the rapid synthesis of a lactam model of our target has been studied. The key step of the delta-lactam formation is a new chemoselective lithiation-annulation method, under high dilution, of a suitable piperidinylcarbamoyl chloride. This precursor was obtained from (2-hydroxyethyl)piperidine in a linear synthetic sequence involving a Corey-Fuchs olefination of the corresponding aldehyde, followed by a selective reduction, using a diimide equivalent, of an iodoalkyne into a (Z)-iodopropene piperidine.

Debenzylation of tertiary amines using phosgene or triphosgene: an efficient and rapid procedure for the preparation of carbamoyl chlorides and unsymmetrical ureas. Application in carbon-11 chemistry.

Efficient and rapid preparations of carbamoyl chlorides and unsymmetrical ureas from tertiary amines and phosgene or its safe equivalent triphosgene [bis(trichloromethyl)carbonate, BTC] are described. First, the reaction of stoichiometric amounts of phosgene with secondary amines was revisited, and it was shown that the formation of carbamoyl chlorides in high yields required careful adjustments of experimental conditions and the use of pyridine as an HCl scavenger. A phosgene-mediated dealkylation of triethylamine was observed when this base was used instead of pyridine.