TABLE 6

Assignment and proposed structures of metabolites of [14C]BIIB021

Assignment12C-Mass [M+H] m/z High-Resolution MSProposed StructureBiotransformationMajor FragmentsRt (minutes)
BIIB021319.1070Embedded Image283, 268, 170, 150, 12047.89
M1321.0865Embedded Imagedemethylation and oxidation267, 170, 13417.6
M2305.0914Embedded Imagedemethylation269, 170, 136, 10823.74
M3349.0825Embedded Imageoxidation313, 298, 269, 254, 180, 15017.6
M4511.1338Embedded Imagehydroxylation and glucuronidation335, 317, 299, 281, 16627.23
M5351.0971Embedded Imageoxidation333, 297, 186, 16628.0
M6301.1405Embedded Imageoxidative dechlorination152, 150, 12033.1
M7335.1016Embedded Imagehydroxylation299,281, 16635.98
M8461.1698Embedded Imageglycylcysteine conjugation386, 358, 316, 237, 150, 12041.5
M9446.1597Embedded Imageacetyl-cysteine conjugation404, 317, 284, 168, 150, 12038.2
M10335.1017Embedded Imagehydroxylation284, 186, 150, 12040.56