Caspofungin Impurity B

Chemical Name: (10R,12S)-N-((2R,6S,9S,11R,12R,14aS,15S,20S,23S,25aS)-20-((R)-3-amino-1-hydroxypropyl)-12-((2-aminoethyl)amino)-23-((1S,2S)-1,2-dihydroxy-2-(4-hydroxyphenyl)ethyl)-2,11,15-trihydroxy-6-((R)-1-hydroxyethyl)-5,8,14,19,22,25-hexaoxotetracosahydro-1H-dipyrrolo[2,1-c:2',1'-l][1,4,7,10,13,16]hexaazacyclohenicosin-9-yl)-10,12-dimethyltetradecanamide

Synonym: (3S,5R)-Atorvastatin Acid Methyl Ester