Estrogenic Steroids, Alkylated

**Definition:** Estrogenic STEROIDS with aliphatic hydrocarbon chain substitution on C17 or other position. 17-alpha-ALKYLATION renders the molecule more stable, resistant to metabolic degradation, and improves oral efficacy. Examples of synthetic alkyl estrogens include ETHINYL ESTRADIOL and MESTRANOL. Substitutions at other sites generates antiestrogenic and cytotoxic properties.

**Tree numbers:** - D06.472.334.851.437.968

**Synonyms:** - Alkyl Estrogenic Steroids - Alkylated Estrogenic Steroids