Exploration and Pharmacokinetic Profiling of Phenylalanine Based Carbamates as Novel Substance P 1–7 Analogues
journal contributionposted on 11.12.2014, 00:00 by Rebecca Fransson, Gunnar Nordvall, Johan Bylund, Anna Carlsson-Jonsson, Jadel M. Kratz, Richard Svensson, Per Artursson, Mathias Hallberg, Anja Sandström
Any type of content formally published in an academic journal, usually following a peer-review process.
The bioactive metabolite of Substance P, the heptapeptide SP1–7 (H-Arg-Pro-Lys-Pro-Gln-Gln-Phe-OH), has been shown to attenuate signs of hyperalgesia in diabetic mice, which indicate a possible use of compounds targeting the SP1–7 binding site as analgesics for neuropathic pain. Aiming at the development of drug-like SP1–7 peptidomimetics we have previously reported on the discovery of H-Phe-Phe-NH2 as a high affinity lead compound. Unfortunately, the pharmacophore of this compound was accompanied by a poor pharmacokinetic (PK) profile. Herein, further lead optimization of H-Phe-Phe-NH2 by substituting the N-terminal phenylalanine for a benzylcarbamate group giving a new type of SP1–7 analogues with good binding affinities is reported. Extensive in vitro as well as in vivo PK characterization is presented for this compound. Evaluation of different C-terminal functional groups, i.e., hydroxamic acid, acyl sulfonamide, acyl cyanamide, acyl hydrazine, and oxadiazole, suggested hydroxamic acid as a bioisosteric replacement for the original primary amide.