Methylprednisolone EP Impurity L Catalogue G112652 CAS 6870-94-6 M.W 358.48 M.F C22H30O4 Specifications FAQs (6S,8S,9S,10R,11S,13S,14S,17R)-17-acetyl-11,17-dihydroxy-6,10,13-trimethyl-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-3-on