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 invention relates to a process for preparing a compound of formula (I) ##STR00001## in particular obeticholic acid and intermediates suitable for its synthesis.

Described are deuterated forms of aminosterols, or a pharmaceutically acceptable salt thereof, wherein one or more hydrogen atoms at one or more positions selected from C1, C2, C3, C4, C5, C6, C7, C8, C9, C11, C12, C14, C15, C16, C17, C18, C19, C20, C21, C22, C23, C24, C25, C26, and C27, are replaced with deuterium.

Described herein are steroids of Formula (I): ##STR00001##
and pharmaceutically acceptable salts thereof; wherein R.sup.1, R.sup.2a, R.sup.2b, R.sup.3, R.sup.4, R.sup.5a, R.sup.5b, R.sup.6, and Z are as defined herein. Such compounds are contemplated useful for the prevention and treatment of a variety of CNS-related conditions, for example, treatment of sleep disorders, mood disorders, schizophrenia spectrum disorders, convulsive disorders, disorders of memory and/or cognition, movement disorders, personality disorders, autism spectrum disorders, pain, traumatic brain injury, vascular diseases, substance abuse disorders and/or withdrawal syndromes, and tinnitus.

Described herein are new anti-cancer compounds and methods of using such compounds, acting through a new mechanism of action by simultaneous inhibition of leukemia inhibitory factor (LIF) and MDM2.

Disclosed is a fluorination method comprising providing an aryl fluorosulfonate and a fluorinating reagent to a reaction mixture; and reacting the aryl fluorosulfonate and the fluorinating reagent to provide a fluorinated aryl species.

Also disclosed is a fluorination method comprising providing , a salt comprising a cation and an aryloxylate, and SO.sub.2F.sub.2 to a reaction mixture; reacting the SO.sub.2F.sub.2 and the ammonium salt to provide a fluorinated aryl species.

Further disclosed a fluorination method comprising providing a compound having the structure Ar-OH to a reaction mixture; where Ar is an aryl or heteroaryl; providing SO.sub.2F.sub.2 to the reaction mixture; providing a fluorinating reagent to the reaction mixture; reacting the SO.sub.2F.sub.2, the fluorinating reagent and the compound having the structure Ar-OH to provide a fluorinated aryl species having the structure Ar-F.

Provided are steroid analogues functionalized with polar substituents at the C3 and/or C20 positions of the steroid ring system that exhibit improved water solubility. Also provided are pharmaceutical compositions comprising the steroid analogues and methods using the novel steroid analogues for the treatment and prevention of neurodegeneration in a patient following injury to the central nervous system.

Provided herein are 19-nor C3,3-disubstituted steroids of Formula (I):

##STR00001##

and pharmaceutically acceptable salts thereof; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are as defined herein, and A is a heteroaryl ring system comprising 3 or 4 nitrogens as defined herein. Such compounds are contemplated useful for the prevention and treatment of a variety of CNS-related conditions, for example, treatment of sleep disorders, mood disorders, schizophrenia spectrum disorders, convulsive disorders, disorders of memory and/or cognition, movement disorders, personality disorders, autism spectrum disorders, pain, traumatic brain injury, vascular diseases, substance abuse disorders and/or withdrawal syndromes, and tinnitus.

Provided herein are 19-nor C3,3-disubstituted C21-pyrazolyl steroids of Formula (I):

##STR00001##

and pharmaceutically acceptable salts thereof; wherein , R.sup.1, R.sup.2, R.sup.3a, R.sup.3b, R.sup.4a, R.sup.4b, R.sup.5, R.sup.6, and R.sup.7 are as defined herein. Such compounds are contemplated useful for the prevention and treatment of a variety of CNS-related conditions, for example, treatment of sleep disorders, mood disorders, schizophrenia spectrum disorders, convulsive disorders, disorders of memory and/or cognition, movement disorders, personality disorders, autism spectrum disorders, pain, traumatic brain injury, vascular diseases, substance abuse disorders and/or withdrawal syndromes, and tinnitus.

Disclosed is a fluorination method comprising providing an aryl fluorosulfonate and a fluorinating reagent to a reaction mixture; and reacting the aryl fluorosulfonate and the fluorinating reagent to provide a fluorinated aryl species. Also disclosed is a fluorination method comprising providing, a salt comprising a cation and an aryloxylate, and SO.sub.2F.sub.2 to a reaction mixture; reacting the SO.sub.2F.sub.2 and the ammonium salt to provide a fluorinated aryl species. Further disclosed a fluorination method comprising providing a compound having the structure ArOH to a reaction mixture; where A is an aryl or heteroaryl; providing SO.sub.2F.sub.2 to the reaction mixture; providing a fluorinating reagent to the reaction mixture; reacting the SO.sub.2F.sub.2, the fluorinating reagent and the compound having the structure ArOH to provide a fluorinated aryl species having the structure ArF.