Methylprednisolone EP Impurity G Catalogue G112647 CAS 93269-35-3 M.W 356.46 M.F C22H28O4 Specifications FAQs (6S,8S,10R,13S,14S,17R)-17-hydroxy-17-(2-hydroxyacetyl)-6,10,13-trimethyl-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-3-one