Melnikov, P.Corbi, P. P.Cuin, A.Cavicchioli, M.Guimaraes, W. R.2014-05-202014-05-202003-10-01Journal of Pharmaceutical Sciences. Hoboken: John Wiley & Sons Inc., v. 92, n. 10, p. 2140-2143, 2003.0022-3549http://hdl.handle.net/11449/33046Sildenafil citrate (Viagra) [I] and sildenafil base [II] are easily and unequivocally characterized by a set of physicochemical methods that include X-ray diffractometry, infrared spectroscopy, and thermal analysis. Monoclinic lattice constants: [I]: a = 26.98 Angstrom; b = 11.95 Angstrom; c = 16.68 Angstrom; beta = 106.97degrees. [II]: a = 8.66 Angstrom; b = 34.27 Angstrom; c = 8.93 Angstrom; beta = 96.63'. Both compounds decompose at 189.4degreesC [I] and 251.9degreesC [II]. Densities and refractive indices are given. (C) 2003 Wiley-Liss, Inc.2140-2143engViagrasildenafil citratesildenafil basebioinorganic chemistryArtigo10.1002/jps.10469WOS:000185692500021Acesso restrito