Compounds of formula (I) can modulate the activity of one or more S 1P receptors. Sphingosine 1-phosphate (S IP) is a lysophospholipid mediator that evokes a variety of cellular responses by stimulation of five members of the endothelial cell differentiation gene (EDG) receptor family, namely S1P1, S1P2, S1P3, S1P4, and S1P5 (formerly EDG1, EDG5, EDG3, EDG6 and EDG8). The EDG receptors are G-protein coupled receptors (GPCRs) and on stimulation propagate second messenger signals via activation of heterotrimeric G-protein alpha (Ga.) subunits and beta-gamma (G()y) dimers.
