Document Report Card

ID: ALA1132237

Journal: J Med Chem

Title: Fluorination of 3-(3-(piperidin-1-yl)propyl)indoles and 3-(3-(piperazin-1-yl)propyl)indoles gives selective human 5-HT1D receptor ligands with improved pharmacokinetic profiles.

Authors: van Niel MB, Collins I, Beer MS, Broughton HB, Cheng SK, Goodacre SC, Heald A, Locker KL, MacLeod AM, Morrison D, Moyes CR, O'Connor D, Pike A, Rowley M, Russell MG, Sohal B, Stanton JA, Thomas S, Verrier H, Watt AP, Castro JL.

Abstract: It has previously been reported that a 3-(3-(piperazin-1-yl)propyl)indole series of 5-HT1D receptor ligands have pharmacokinetic advantages over the corresponding 3-(3-(piperidin-1-yl)propyl)indole series and that the reduced pKa of the piperazines compared to the piperidines may be one possible explanation for these differences. To investigate this proposal we have developed versatile synthetic strategies for the incorporation of fluorine into these ligands, producing novel series of 4-fluoropiperidines, 3-fluoro-4-aminopiperidines, and both piperazine and piperidine derivatives with one or two fluorines in the propyl linker. Ligands were identified which maintained high affinity and selectivity for the 5-HT1D receptor and showed agonist efficacy in vitro. The incorporation of fluorine was found to significantly reduce the pKa of the compounds, and this reduction of basicity was shown to have a dramatic, beneficial influence on oral absorption, although the effect on oral bioavailability could not always be accurately predicted.

CiteXplore: 10377215

DOI: 10.1021/jm981133m