کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9770162 | 1501940 | 2005 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Crystal structure of nitarsone determined from synchrotron X-ray powder diffraction data
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موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
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چکیده انگلیسی
The crystal structure of nitarsone, 4-nitrophenylarsonic acid, a substitute for nifursol and dimetridazole in the prevention and treatment of turkey histomoniasis desease, has been determined from synchrotron X-ray powder diffraction data. Nitarsone crystallizes in the monoclinic space group P21/n with unit cell parameters a=7.46413(5), b=25.68543(17), c=4.657388(32)Â Ã
, β=105.4670(5)°. The structure was solved using simulated annealing techniques by treating the molecule as a rigid body for which the configuration resulting from an energy minimization was used in slightly adapted form. Structure refinement treated the NO2 and the AsO(OH)2 groups as free groups, leading to final confidence factors Rp=0.059 and Rwp=0.071. The crystal structure contains 4 molecules per unit cell that are hydrogen bonded to form infinite chains of dimers running along the c-axis. Nitarsone's low toxicity when compared with inorganic sources of arsenic is explained by the existence of a partial double C-As bond (1.866(5) Ã
) which confers greater stability so that under physiological conditions nitarsone is not converted to mineral-like As V or III.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure - Volume 743, Issues 1â3, 31 May 2005, Pages 223-228
Journal: Journal of Molecular Structure - Volume 743, Issues 1â3, 31 May 2005, Pages 223-228
نویسندگان
A. van der Lee, P. Richez, C. Tapiero,