VLA-4 is implicated in several inflammatory and autoimmune disease states. A series of cyclic P-amino acids (beta-aa) was studied as VLA-4 antagonists. Binding affinity was highly dependent on the dihedral angle (phi) between the amino and the carboxyl termini of the beta-aa. Compound 5m where the beta-aa is embedded in a bicycle possesses the most preferred phi (120 degrees). It is a potent and bioavailable VLA-4 antagonist (VCAM-Ig alpha 4 beta 1 IC50 = 54 nM, rat po F = 49%). (c) 2006 Elsevier Ltd. All rights reserved.
VLA-4 is implicated in several inflammatory and autoimmune disease states. A series of cyclic P-amino acids (beta-aa) was studied as VLA-4 antagonists. Binding affinity was highly dependent on the dihedral angle (phi) between the amino and the carboxyl termini of the beta-aa. Compound 5m where the beta-aa is embedded in a bicycle possesses the most preferred phi (120 degrees). It is a potent and bioavailable VLA-4 antagonist (VCAM-Ig alpha 4 beta 1 IC50 = 54 nM, rat po F = 49%). (c) 2006 Elsevier Ltd. All rights reserved.