Dexamethasone 9,11-Epoxide (8DM) CAS 24916-90-3

2.Physical and Chemical Properties

• Appearance: White to off-white crystalline powder
• Melting point: Approximately 185–200 °C
• Specific optical rotation [α]D²⁰: Approximately +85° to +100° (c 1.0, chloroform)
• Solubility: Readily soluble in dichloromethane, chloroform, ethyl acetate, acetone; slightly soluble in methanol, ethanol; insoluble in water
• Stability: Stable at ambient temperature; store sealed, protected from light, at low temperature; the 9,11-epoxide and the Δ1,4-3-ketone are the key reactive handles for downstream fluorination

3.Main Functions and Applications (What are its uses?)

Key intermediate for dexamethasone (core application): 8DM is the pivotal intermediate in the industrial synthesis of dexamethasone, a highly potent synthetic glucocorticoid. The 9,11-epoxide ring is opened by hydrogen fluoride in a single step to introduce both the 9α-fluoro and the 11β-hydroxy groups; the 16α-methyl group is already pre- installed; the 21-acetate protecting group is removed at a later stage to give the free 21-hydroxyl.

Downstream API - Dexamethasone:

A potent anti-inflammatory, immunosuppressive and anti-allergic corticosteroid.

Used in the treatment of inflammatory disorders, autoimmune diseases, allergic conditions, severe asthma and cerebral edema.

Dosage forms include tablets, injections, eye drops and ointments.

Ester and salt derivatives: Also the starting material for dexamethasone 21-acetate, dexamethasone sodium phosphate and dexamethasone palmitate, which are widely used in ophthalmic and injectable formulations.

Advantages of the epoxide platform: The fixed 16α-methyl and the 9,11-epoxide handle provide high regio- and stereoselectivity in the one-step fluorination, shortening the route and improving process economics.

Quality control reference: Also used as a related-substance reference standard in the quality control of dexamethasone intermediates and APIs.