Spectrometry, Mass, Electrospray Ionization electrospray mass spectrometry 12 nuclear magnetic resonance spectroscopy Magnetic Resonance Spectroscopy 10 article 10 chemistry 10 Humans 4 Mass spectrometry 4 Spectrophotometry, Ultraviolet 4 drug derivative 4 high performance liquid chromatography 4 human 4 ultraviolet spectrophotometry 4 unclassified drug 4 (17beta) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxylate 2 (17beta) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxylic acid 2 (17beta) n ((t butylcarbamoyl)methyl) n (2 chlorophenyl) 4,4 dimethyl 3 hydroxyandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (2 ethyl 6 methylphenyl) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (2 fluorophenyl) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (2 naphthyl) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (4 chlorophenyl) 4,4 dimethyl 3 hydroxyandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (4 chlorophenyl) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (4 fluorophenyl) 4,4 dimethyl 3 hydroxyandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (4 fluorophenyl) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (4 methoxyphenyl) 4,4 dimethyl 3 hydroxyandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (4 methoxyphenyl) 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n (4 methylphenyl) 4,4 dimethyl 3 hydroxyandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n phenyl 4,4 dimethyl 3 hydroxyandrost 5 ene 17 carboxamide 2 (17beta) n ((t butylcarbamoyl)methyl) n phenyl 4,4 dimethyl 3 oxoandrost 5 ene 17 carboxamide 2 (3-chloro-2-hydroxypropyl)trimethylammonium chloride 2