title: Supramolecular synthon polymorphism in 2 : 1 co-crystal of 4-hydroxybenzoic acid and 2,3,5,6-tetramethylpyrazine.
abstract: Co-crystals of 4-hydroxybenzoic acid and 2,3,5,6-tetramethylpyrazine (2 : 1) exhibit the first supramolecular synthon polymorphism in a co-crystal; metastable anti-hierarchic polymorph I converts to stable hierarchic form II.
authors.affiliation: Department of Analytical Research, Discovery Research, Dr. Reddy's Laboratories Ltd., Miyapur, Hyderabad 500 049, India.
authors.forename: B R
authors.initials: BR
authors.lastname: Sreekanth
authors.forename: Peddy
authors.initials: P
authors.lastname: Vishweshwar
authors.forename: K
authors.initials: K
authors.lastname: Vyas
mesh_terms: D003460:Crystallization; D006860:Hydrogen Bonding; D008958:Models, Molecular; D010226:Parabens / Q000737:chemistry*; D011719:Pyrazines / Q000737:chemistry*
chemical_list: D010226:Parabens; D011719:Pyrazines; C038193:4-hydroxybenzoic acid; C017953:tetramethylpyrazine