title: Studies on the enantiomers of RC-33 as neuroprotective agents: isolation, configurational assignment, and preliminary biological profile.
abstract: In this study we addressed the role of chirality in the biological activity of RC-33, recently studied by us in its racemic form. An asymmetric synthesis procedure was the first experiment, leading to the desired enantioenriched RC-33 but with an enantiomeric excess (ee) not good enough for supporting the in vitro investigation. An enantioselective high-performance liquid chromatography (HPLC) procedure was then successfully carried out, yielding both RC-33 enantiomers in amounts and optical purity suitable for the pharmacological study. The absolute configuration of pure enantiomers was easily assigned exploiting the asymmetric synthesis previously devised. As emerged in the preliminary in vitro biological investigation, (S)- and (R)-RC-33 possess a comparable affinity towards the σ1 receptor and a very a similar behavior in the calcium influx assay, resulting in an equally effective σ1 receptor agonist. Overall, the results obtained so far suggest that the interaction with the biological target is nonstereoselective and leads us to hypothesize that there is a lack of stereoselectivity in the biological activity of RC-33.
authors.affiliation: Department of Drug Sciences, Medicinal Chemistry and Pharmaceutical Technology section, University of Pavia, Pavia, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Rossi
authors.forename: Alice
authors.initials: A
authors.lastname: Pedrali
authors.forename: Annamaria
authors.initials: A
authors.lastname: Marra
authors.forename: Luca
authors.initials: L
authors.lastname: Pignataro
authors.forename: Dirk
authors.initials: D
authors.lastname: Schepmann
authors.forename: Bernhard
authors.initials: B
authors.lastname: Wünsch
authors.forename: Lian
authors.initials: L
authors.lastname: Ye
authors.forename: Kristina
authors.initials: K
authors.lastname: Leuner
authors.forename: Marco
authors.initials: M
authors.lastname: Peviani
authors.forename: Daniela
authors.initials: D
authors.lastname: Curti
authors.forename: Ornella
authors.initials: O
authors.lastname: Azzolina
authors.forename: Simona
authors.initials: S
authors.lastname: Collina
mesh_terms: D000818:Animals; D001713:Biphenyl Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D006168:Guinea Pigs; D018696:Neuroprotective Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D016716:PC12 Cells; D010880:Piperidines / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D017480:Receptors, sigma / Q000819:agonists; D013237:Stereoisomerism
chemical_list: C584299:1-(3-biphenyl-4-ylbutyl)piperidine; D001713:Biphenyl Compounds; D018696:Neuroprotective Agents; D010880:Piperidines; D017480:Receptors, sigma
keywords: absolute configuration assignment; asymmetric hydrogenation; chemical correlation; enantioselective HPLC; neuroprotective agents; σ1 receptor agonists