title: 2-imino-thiazolidin-4-one derivatives as potent, orally active S1P1 receptor agonists.
abstract: Sphingosine-1-phosphate (S1P) is a widespread lysophospholipid which displays a wealth of biological effects. Extracellular S1P conveys its activity through five specific G-protein coupled receptors numbered S1P(1) through S1P(5). Agonists of the S1P(1) receptor block the egress of T-lymphocytes from thymus and lymphoid organs and hold promise for the oral treatment of autoimmune disorders. Here, we report on the discovery and detailed structure-activity relationships of a novel class of S1P(1) receptor agonists based on the 2-imino-thiazolidin-4-one scaffold. Compound 8bo (ACT-128800) emerged from this series and is a potent, selective, and orally active S1P(1) receptor agonist selected for clinical development. In the rat, maximal reduction of circulating lymphocytes was reached at a dose of 3 mg/kg. The duration of lymphocyte sequestration was dose dependent. At a dose of 100 mg/kg, the effect on lymphocyte counts was fully reversible within less than 36 h. Pharmacokinetic investigation of 8bo in beagle dogs suggests that the compound is suitable for once daily dosing in humans.
authors.affiliation: Drug Discovery Chemistry, Actelion Pharmaceuticals Ltd., Allschwil, Switzerland. martin.bolli@actelion.com
authors.forename: Martin H
authors.initials: MH
authors.lastname: Bolli
authors.forename: Stefan
authors.initials: S
authors.lastname: Abele
authors.forename: Christoph
authors.initials: C
authors.lastname: Binkert
authors.forename: Roberto
authors.initials: R
authors.lastname: Bravo
authors.forename: Stephan
authors.initials: S
authors.lastname: Buchmann
authors.forename: Daniel
authors.initials: D
authors.lastname: Bur
authors.forename: John
authors.initials: J
authors.lastname: Gatfield
authors.forename: Patrick
authors.initials: P
authors.lastname: Hess
authors.forename: Christopher
authors.initials: C
authors.lastname: Kohl
authors.forename: Céline
authors.initials: C
authors.lastname: Mangold
authors.forename: Boris
authors.initials: B
authors.lastname: Mathys
authors.forename: Katalin
authors.initials: K
authors.lastname: Menyhart
authors.forename: Claus
authors.initials: C
authors.lastname: Müller
authors.forename: Oliver
authors.initials: O
authors.lastname: Nayler
authors.forename: Michael
authors.initials: M
authors.lastname: Scherz
authors.forename: Gunther
authors.initials: G
authors.lastname: Schmidt
authors.forename: Virginie
authors.initials: V
authors.lastname: Sippel
authors.forename: Beat
authors.initials: B
authors.lastname: Steiner
authors.forename: Daniel
authors.initials: D
authors.lastname: Strasser
authors.forename: Alexander
authors.initials: A
authors.lastname: Treiber
authors.forename: Thomas
authors.initials: T
authors.lastname: Weller
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D004285:Dogs; D022781:Hepatocytes / Q000378:metabolism; D057166:High-Throughput Screening Assays; D006801:Humans; D007097:Imines / Q000138:chemical synthesis* / Q000493:pharmacokinetics / Q000494:pharmacology; D018655:Lymphocyte Count; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D011869:Radioligand Assay; D051381:Rats; D017208:Rats, Wistar; D049349:Receptors, Lysosphingolipid / Q000819:agonists*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013844:Thiazoles / Q000138:chemical synthesis* / Q000493:pharmacokinetics / Q000494:pharmacology; D053778:Thiazolidines / Q000138:chemical synthesis* / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: D007097:Imines; D049349:Receptors, Lysosphingolipid; D013844:Thiazoles; D053778:Thiazolidines; C550169:ponesimod