Crystal structure determination of mebendazole form A using high-resolution synchrotron x-ray powder diffraction data

✍ Scribed by Fabio Furlan Ferreira; Selma Gutierrez Antonio; Paulo César Pires Rosa; Carlos de Oliveira Paiva-Santos

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 349 KB
• Volume: 99
• Category: Article
• ISSN: 0022-3549
• DOI: 10.1002/jps.21902

✦ Synopsis

The crystal structure determination of mebendazole form A, an anthelmintic drug, was performed for the first time by applying the DASH software program to synchrotron X-ray powder diffraction data, and supported by a satisfying Rietveld fit. This polymorph of mebendazole crystallizes in a triclinic (P1) space group, with unit-cell parameters a = 5.5044(2) A, b = 11.2872(2) A, c = 12.5276(5) A, alpha = 66.694(2) degrees, beta = 82.959(2) degrees, gamma = 78.443(2) degrees, V = 699.52(5) A(3), Z = 2, M = 295.293 g mol(-1), rho(calc) = 1.4021 g cm(-3), and rho(meas) = 1.3935(66) g cm(-3), which were obtained by means of the unit-cell formula weight and a picnometric measurement, respectively. The goodness-of-fit and R-factors were, respectively: chi(2) = 1.746, R(F)(2) = 1.69%, R(wp) = 5.72%, and R(p) = 4.37%. A weak nonclassical hydrogen bond involving the atoms N(3)-H(23)...O(11) may be responsible for the greater stability of the polymorphic form A of mebendazole due to the strongest electronegativity of nitrogen.