20 beta-hydroxy-6-alpha-methylprednisone

20 beta-hydroxy-6-alpha-methylprednisone is a glucocorticoid derivative featuring a hydroxyl group at the 20β position and a 6α-methyl substitution on the pregnane skeleton. This compound retains the 11-oxo and 17α-hydroxy functionalities characteristic of the parent drug, 6-alpha-Methylprednisolone, while introducing a secondary alcohol at C20. Structurally, it represents a synthetic byproduct formed during oxidation processes targeting the C20 position of the methylated precursor. Its distinct stereochemistry and functional group profile enable its use as an HPLC reference standard for quantifying impurities in 6-alpha-Methylprednisolone formulations.