Crystal structure of alfuzosin hydrochloride, C19H28N5O4Cl

The crystal structure of anhydrous alfuzosin hydrochloride has been solved and refined using laboratory X-ray powder diffraction data and optimized using density functional theory techniques. Anhydrous alfuzosin hydrochloride crystallizes in space group P-1 with a = 9.3214(16), b = 9.3997(29), c = 12.6172(64) Å, α = 107.993(11), β = 100.386(9), γ = 90.229(6)°, V = 1032.1(10) Å3, and Z = 2 at ambient conditions. Thermal expansion is anisotropic, being 8× larger in the c-direction than in the other two. The crystal structure is characterized by a stack of planar fused rings along the b-axis, and layers of the more-corrugated portion of the molecule parallel to the ab-plane. There are two strong N–H⋯Cl hydrogen bonds, as well as seven C-H⋯Cl hydrogen bonds. The powder patterns have been submitted to ICDD for inclusion in the Powder Diffraction File™ (PDF®).