C21H28O2

The molecular formula C21H28O2 (molar mass: 312.44 g/mol) may refer to:


 * 11-Dehydroprogesterone
 * Demegestone
 * Dydrogesterone
 * Ethisterone, a progesterone hormone
 * Guggulsterone
 * Levonorgestrel
 * Norgestrel, a progestin (Dextronorgestrel)
 * Pregna-4,20-dien-3,6-dione
 * Tetrahydrogestrinone, an anabolic steroid
 * Tibolone, a steroid hormone
 * Δ4-Tibolone, a metabolite of tibolone
 * Trimethyltrienolone
 * 7,8-Dihydrocannabinol