英文别名4-Methyl-ethinyl estradiol; Ethinylestradiol impurity K [EP]; Ethinylestradiol specified impurity K [EP]; 4-Methyl-19-nor-17alpha-pregna-1,3,5(10)-trien-20-yne-3,17-diol; 19-Norpregna-1,3,5(10)-trien-20-yne-3,17-diol, 4-methyl-, (17alpha)-; Ethinylestradiol impurity K; Ethinylestradiol specified impurity K; 4-Methyl Ethynyl Estradiol; Ethinylestradiol EP Impurity K; (8R,9S,13S,14S,17R)-17-ethynyl-4,13-dimethyl-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthrene-3,17-diol; Ethinyl Estradiol Impurity K; (17a)-4-Methyl-19-norpregna-1,3,5(10)-trien-20-yne-3,17-diol; 4-Methyl-19-nor-17a-pregna-1,3,5(10)-trien-20-yne-3,17-diol; (17α)-4-Methyl-19-norpregna-1,3,5(10)-trien-20-yne-3,17-diol; Ethinylestradiol EP Imp K; 19-Norpregna-1,3,5(10)-trien-20-yne-3,17-diol, 4-methyl-, (17α)-; 4-METHYL-17-ETHYNYL ESTRADIOL 
