Provided herein is a compound of Formula (I):

##STR00001##

or a pharmaceutically acceptable salt thereof, wherein R.sup.1a, R.sup.1b, R.sup.2a, R.sup.2b, R.sup.3, R.sup.4a, R.sup.4b, R.sup.5, R.sup.6a, R.sup.16b, R.sup.7a, R.sup.7a, R.sup.11a, R.sup.11b, R.sup.12a, R.sup.12b, R.sup.16a, R.sup.16b, R.sup.19, R.sup.11a, R.sup.22, R.sup.X, R.sup.Y and n are defined herein. Also provided herein are pharmaceutical compositions comprising a compound of Formula (I) and methods of using the compounds, e.g., in the treatment of CNS-related disorders.

Methods for producing enantiodefined polycyclic compounds, particularly tetracyclic compounds, are provided. More particularly, synthetic methods for producing biologically active enantiodefined steroidal compositions of both natural (nat-) and unnatural (ent-) absolute stereochemistry are provided. An exemplary method for manufacturing a tetracyclic compound comprises a step of forming a hydrindane intermediate through coupling of a suitably functionalized enyne with a suitably functionalized alkyne and subsequently performing an intramolecular ring-closing reaction to form the tetracyclic compound. Steroidal compounds obtained by this method and methods of using such steroidal compounds in human and/or animal therapeutics and medicines are also provided.

Methods for producing enantiodefined polycyclic compounds, particularly tetracyclic compounds, are provided. More particularly, synthetic methods for producing biologically active enantiodefined steroidal compositions of both natural (nat-) and unnatural (ent-) absolute stereochemistry are provided. An exemplary method for manufacturing a tetracyclic compound comprises a step of forming a hydrindane intermediate through coupling of a suitably functionalized enyne with a suitably functionalized alkyne and subsequently performing an intramolecular ring-closing reaction to form the tetracyclic compound. Steroidal compounds obtained by this method and methods of using such steroidal compounds in human and/or animal therapeutics and medicines are also provided.