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.