title: Application of spectropolarimetry in drug analysis. VII. Difference spectropolarimetric determination of 17-ketosteroid impurity in ethynylsteroids.
mesh_terms: D015068:17-Ketosteroids / Q000032:analysis*; D004997:Ethinyl Estradiol / Q000302:isolation & purification*; D008656:Mestranol / Q000302:isolation & purification*; D009905:Optical Rotatory Dispersion / Q000379:methods
chemical_list: D015068:17-Ketosteroids; D004997:Ethinyl Estradiol; D008656:Mestranol