title: Multicomponent crystals of erlotinib.
abstract: Erlotinib [systematic name: N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine], a small-molecule epidermal growth factor receptor inhibitor, useful for the treatment of non-small-cell lung cancer, has been crystallized as erlotinib monohydrate, C(22)H(23)N(3)O(4).H(2)O, (I), the erlotinib hemioxalate salt [systematic name: 4-amino-N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-1-ium hemioxalate], C(22)H(24)N(3)O(4)(+).0.5C(2)O(4)(2-), (II), and the cocrystal erlotinib fumaric acid hemisolvate dihydrate, C(22)H(23)N(3)O(4).0.5C(4)H(4)O(4).2H(2)O, (III). In (II) and (III), the oxalate anion and the fumaric acid molecule are located across inversion centres. The water molecules in (I) and (III) play an active role in hydrogen-bonding interactions which lead to the formation of tetrameric and hexameric hydrogen-bonded networks, while in (II) the cations and anions form a tetrameric hydrogen-bonded network in the crystal packing. The title multicomponent crystals of erlotinib have been elucidated to study the assembly of molecules through intermolecular interactions, such as hydrogen bonds and aromatic pi-pi stacking.
authors.affiliation: Laboratory of X-ray Crystallography, Indian Institute of Chemical Technology, Hyderabad 500 007, India. sshiya@yahoo.com
authors.forename: B
authors.initials: B
authors.lastname: Sridhar
authors.forename: K
authors.initials: K
authors.lastname: Ravikumar
authors.forename: Harihara
authors.initials: H
authors.lastname: Krishnan
authors.forename: A N
authors.initials: AN
authors.lastname: Singh
mesh_terms: D018360:Crystallography, X-Ray; D000069347:Erlotinib Hydrochloride; D005650:Fumarates / Q000737:chemistry; D006860:Hydrogen Bonding; D008958:Models, Molecular; D010070:Oxalates / Q000737:chemistry; D011799:Quinazolines / Q000737:chemistry*
chemical_list: D005650:Fumarates; D010070:Oxalates; D011799:Quinazolines; C032005:fumaric acid; D000069347:Erlotinib Hydrochloride