YK11 Chemical data 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 YK11 Raw Powder Specification Data: Product Name YK11 CAS No. 431579-34-9 Packing 1KG Production date 2015-11-01 Shelf life 2017-10-30 Standard adopted Enterprise Standard Items of analysis Specification Results Appearance White to off white powder Conforms Identification IR, HPLC …