The present disclosure relates to stereodefined polycyclic (e.g., tetracyclic) compounds that contain quaternary centers at one or multiple ring fusions, synthetic methods for preparing such compounds, and methods of using such compounds to treat a disease, such as a brain tumor and, particularly, a glioma.

Provided herein is a compound of Formula (I-I), or a pharmaceutically acceptable salt thereof, wherein the variables are defined herein. Also provided herein are pharmaceutical compositions comprising a compound of Formula (I-I), and methods of using the compounds, e.g. in the treatment of CNS-related disorders.

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The invention provides a novel, general, and facile strategy for the creation of small molecules with high structural and stereochemical complexity. Aspects of the methods include ring system distortion reactions that are systematically applied to rapidly convert readily available natural products to structurally complex compounds with diverse molecular architectures. Through evaluation of chemical properties including fraction of sp.sup.3 carbons, ClogP, and the number of stereogenic centers, these compounds are shown to be significantly more complex and diverse than those in standard screening collections. This approach is demonstrated with natural products (gibberellic acid, adrenosterone, and quinine) from three different structural classes, and methods are described for the application of this strategy to any suitable natural product.

The present disclosure relates to stereodefined polycyclic (e.g., tetracyclic) compounds that contain quaternary centers at one or multiple ring fusions, synthetic methods for preparing such compounds, and methods of using such compounds to treat a disease, such as a brain tumor and, particularly, a glioma.

The present disclosure relates to methods of producing enantiodefined polycyclic ring compounds. More particularly, the present disclosure provides synthetic methods of producing biologically active enantiodefined steroidal compositions of both natural and unnatural (ent-) absolute stereochemistry. The present disclosure also relates to methods of using said steroidal compositions prepared from this method as biologically active (e.g., therapeutic) components in compositions and/or directly as human and/or animal therapeutics and medicines. The present disclosure further relates to methods of producing and using said steroidal compositions of matter in chemical, pharmacological, and biological studies and research.

The present application discloses, among other things, asymmetric synthesis a diastereomeric compound of formula (I) (e.g., -anordrin) or salt thereof. Also provided are methods and compositions for treatment of estrogen deficiency as well as preventing or reducing an estrogen deficiency symptom using a diastereomeric compound of formula (I) (e.g., -anordrin) or salt thereof alone or in combination with at least one additional agent. Further provided are methods and compositions for reducing a side effect of an additional agent in the context of combination therapy with a diastereomeric compound of formula (I) (e.g., -anordrin) or salt thereof.

The present invention refers to a new process for the synthesis of (9,10)-pregn-4-ene-3,20-dione, commonly known as retroprogesterone, having the formula (1) shown below. ##STR00001##

The present invention refers to a new process for the synthesis of (9,10)-pregn-4-ene-3,20-dione, commonly known as retroprogesterone, having the formula (1) shown below.

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A method of reducing an aromatic ring or a cyclic, allylic ether in a compound includes preparing a reaction mixture including a compound including an aromatic moiety or a cyclic, allylic ether moiety, an alkali metal, and either ethylenediamine, diethylenetriamine, triethylenetetramine, or a combination thereof, in an ether solvent; and reacting the reaction mixture at from ?20? C. to 30? C. for a time sufficient to reduce a double bond in the aromatic moiety to a single bond or to reduce the cyclic, allylic ether moiety.

Provided herein is a compound of Formula (I-I)

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or a pharmaceutically acceptable salt thereof, wherein the variables are defined herein. Also provided herein are pharmaceutical compositions comprising a compound of Formula (I-I), and methods of using the compounds, e.g., in the treatment of CNS-related disorders.