Novel S1P<sub>1</sub> Receptor Agonists - Part 2: From Bicyclo[3.1.0]hexane-Fused Thiophenes to Isobutyl Substituted Thiophenes
作者:Martin H. Bolli、Jörg Velker、Claus Müller、Boris Mathys、Magdalena Birker、Roberto Bravo、Daniel Bur、Ruben de Kanter、Patrick Hess、Christopher Kohl、David Lehmann、Solange Meyer、Oliver Nayler、Markus Rey、Michael Scherz、Beat Steiner
DOI:10.1021/jm401456d
日期:2014.1.9
Previously, we reported on the discovery of a novel series of bicyclo[3.1.0]hexane fused thiophene derivatives that serve as potent and selective S1P(1), receptor agonists. Here, we discuss our efforts to simplify the bicyclohexane fused thiophene head. In a first step the bicyclohexane moiety could be replaced by a simpler, less rigid cyclohexane ring without compromising the SIP receptor affinity profile of these novel compounds. In a second step, the thiophene head was simplified even further by replacing the cyclohexane ring with an isobutyl group attached either to position 4 or position S of the thiophene. These structurally much simpler headgroups again furnished potent and selective S1P(1) agonists (e.g., 87), which efficiently and dose dependently reduced the number of circulating lymphocytes upon oral administration to male Wistar rats. For several compounds discussed in this report lymphatic transport is an important route of absorption that may offer opportunities for a tissue targeted approach with minimal plasma exposure.