Ketotifen Fumarate EP Impurity B

Chemical Name: 4-Hydroxy-9,10-Dehydro-10-Methoxy Ketotifen ; (4RS)-10-methoxy-4-(1-methylpiperidin-4-yl)-4H-benzo[4,5]cyclohepta[1,2-b]thiophen-4-ol

Synonym: 2-((8S,13S,14S,17R)-17-hydroxy-13-methyl-3-oxo-2,3,6,7,8,11,12,13,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl-2,2,4,8,11,11-d6)acetonitrile-d2