The metabolism of the synthetic progestational compound Ro 4-8347.
The retrosteroid Ro 4-8347 is discussed with attention given to: 1) its rate of absorption from the gastro-intestinal tract, 2) its progestational activity when administered orally, 3) its distribution among various tissues after ingestion, 4) its hormonal activity and 5) characteristics of its principle metabolite. Ro 4-8347 differs structurally from dydrogesterone only in that Ro 4-8347 has an additional double bond between carbons 1 and 2 in the A ring and a chlorine at carbon 6. The absorption rate from the gastro-intestinal tract for both compounds is similar but the clearance rate through the kidneys is 5 times greater for dydrogesterone. Ro 4-8347 showed consistent progestational activity at 2 mg/day. Its tissue distribution is similar to progesterone. It is excreted as the 3-Keto-20-hydroxy derivative, which probably has progestational activity.