title: Polymorphic form IV of olanzapine.
abstract: 2-Methyl-4-(4-methylpiperazin-1-yl)-10H-thieno[2,3-b][1,5]benzodiazepine, C(17)H(20)N(4)S, commonly known as olanzapine, is a psychotropic agent that belongs to the thienobenzodiazepine class of drugs. A new polymorph form IV was obtained upon attempted cocrystallization with nicotinamide in a 1:1 ratio from an ethyl acetate solution. Two butterfly-like molecules form centrosymmetric dimers stabilized by weak C-H···π interactions between the 4-methylpiperazin-1-yl fragment and the benzene/thiophene aromatic system. Form IV consists of a herringbone arrangement of dimers, whereas the previously reported form II has parallel dimers. Both crystal structures are sustained by an N-H···N hydrogen bond.
authors: School of Chemistry, University of Hyderabad, Hyderabad 500 046, India.
authors: Ranjit
authors: R
authors: Thakuria
authors: Ashwini
authors: A
authors: Nangia
mesh_terms: D001569:Benzodiazepines / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D015394:Molecular Structure; D000077152:Olanzapine
chemical_list: D001569:Benzodiazepines; D000077152:Olanzapine