Formestane

• CAT Number: A000625
• CAS Number: 566-48-3
• Molecular Formula: C19H26O3
• Molecular Weight: 302.41
• Purity: ≥95%
• Synonyms: 566-48-3; 4-Hydroxyandrost-4-ene-3,17-dione; 4-Hydroxyandrostenedione; Lentaron; CGP-32349
• Target: Aromatase
• Solubility: Soluble in DMSO > 10 mM
• Storage: -20°C
• IUPAC Name: (8R,9S,10R,13S,14S)-4-hydroxy-10,13-dimethyl-2,6,7,8,9,11,12,14,15,16-decahydro-1H-cyclopenta[a]phenanthrene-3,17-dione
• InChI: 1S/C19H26O3/c1-18-10-8-15(20)17(22)14(18)4-3-11-12-5-6-16(21)19(12,2)9-7-13(11)18/h11-13,22H,3-10H2,1-2H3/t11-,12-,13-,18+,19-/m0/s1
• InChIKey: OSVMTWJCGUFAOD-KZQROQTASA-N
• SMILES: CC12CCC(=O)C(=C1CCC3C2CCC4(C3CCC4=O)C)O

Formestane (Cat No.: A000625) is a steroidal aromatase inhibitor used primarily in the treatment of estrogen-dependent breast cancer in postmenopausal women. It works by irreversibly binding to and inactivating the aromatase enzyme, thereby blocking the conversion of androgens to estrogens and reducing estrogen levels. This hormonal suppression helps slow the growth of estrogen-responsive tumors. Administered via intramuscular injection, formestane was one of the first aromatase inhibitors but has largely been replaced by newer oral agents. Side effects may include hot flashes, fatigue, and bone loss.

Reference

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