A series of substituted 3, 6-diphenyl-7H-[1, 2, 4] triazolo [3, 4-b][1, 3, 4] thiadiazines were prepared and analyzed as inhibitors of phosphodiesterase 4 (PDE4). Synthesis, structure– activity relationships, and the selectivity of a highly potent analogue against related phosphodiesterase isoforms are presented.
