Steroids with a Heteroatom in Ring

Steroid Chemistry at a Glance Daniel Lednicer 2011 John Wiley Sons, Ltd 

In much the same vein, condensation with lithium acetylide affords the corresponding 17a-ethynyl-17/3-hydroxyl derivative. None of these target compounds showed much in the way of hormonal activity. 

Replacement of the carbon atom at C4 by lactam-nitrogen also leads to compounds with pharmacological activity. The several FDA-licensed compounds in this small class act as androgen antagonists, in direct contrast to oxandrolone, which presumably acts on the same receptor. 

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