Urazole compounds having the formula (I), or pharmaceutically-acceptable salts thereof, are effective as anti-inflammatory or immunosuppressive agents, wherein L and K are O or S; Q is a linker such as —O—, —S—, C(═O), and so forth, R1 is an aryl or heteroaryl group, and R3, R4a, R4c, Z, r, s and t are as defined in the specification.