Disclosed are compounds of Formula (I) or a salt thereof, wherein: Y is Formula (II), or Formula (III); R1, R2, R2a, R2b, R2c, R3, R4, R5, m, and n are defined herein. Also disclosed are methods of using such compounds as inhibitors of signaling through Toll-like receptor 7, or 8, or 9, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating inflammatory and autoimmune diseases.