Celecoxib cocrystal polymorphs with cyclic amides: Synthons of a sulfonamide drug with carboxamide coformers

Abstract

The trimorphic cocrystals of celecoxib with δ-valerolactam contain sulfonamide dimers and catemers together with carboxamide dimers, whereas the caprolactam cocrystal is sustained by a SO2N-H⋯H-NOC heterosynthon. The alternation of synthons with even-odd ring coformers offers a crystal engineering approach to sulfonamide-carboxamide cocrystals. © 2014 The Royal Society of Chemistry.