Chemical Name:(17a,20E)-17,20-[(1-Methoxyethylidene)bis(oxy)]-3-oxo-19-norpregna- 4,20-diene-21-carboxylic Acid Methyl Ester. CAS: 431579-34-9 or 1370003-76-1 Molecular formula: C25H34O6C25H34O6 Molecular weight: 430.54 Purity:99% Appearance:White Powder Grade:Pharmaceutical Grade