Disclosed are compounds of Formula (I)or a stereoisomer or a pharmaceutically acceptable salt thereof, wherein:A isQ is a substituted 5-membered monocyclic heteroaryl group;W is CH2, O, or NH; and R1, R2, R3, R4, R5, R6, m, n, t, and x are defined herein. Also disclosed are methods of using such compounds as selective agonists for G protein-coupled receptor S1P1, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating, preventing, or slowing the progression of diseases or disorders in a variety of therapeutic areas, such as autoimmune diseases and vascular disease.