Pharma & Specialty Chemical Standards

Estradiol (IUPAC: 1,3,5(10)-estratriene-3,17β-diol; molecular formula C18H24O2, molecular weight 272.38 g/mol) is a steroidal estrogen belonging to the class of C18 steroids. Its structure features three hydroxyl groups (3-hydroxy, 17β-hydroxy) and a conjugated aromatic A ring. Therapeutically, it is used in hormone replacement therapy and contraception. Physicochemically, it is a white crystalline solid with low water solubility (1.4 mg/mL) and high lipid solubility, melting at 178–182°C. It acts via binding to estrogen receptors (ERα/ERβ), modulating gene transcription through estrogen response elements (EREs) in target tissues, influencing cellular proliferation and differentiation.