Ulipristal

Chemical Classification and Structural Family

This compound belongs to the norpregnane family of synthetic steroids, specifically classified as a 19-norprogesterone derivative. The compound's structural foundation lies within the steroid hormone family, characterized by its four-ring cyclopentanoperhydrophenanthrene backbone typical of steroid molecules. This structural classification places this compound among the norsteroids, which are synthetic compounds derived from naturally occurring steroid hormones through specific molecular modifications.

The chemical identity of this compound is defined by its molecular formula $$ \text{C}{28}\text{H}{35}\text{NO}_3 $$ and molecular weight of 433.58 daltons. The compound's International Union of Pure and Applied Chemistry name reflects its complex stereochemical arrangement: (8S,11R,13S,14S,17R)-17-acetyl-11-[4-(dimethylamino)phenyl]-13-methyl-3-oxo-1,2,6,7,8,11,12,14,15,16-decahydrocyclopenta[a]phenanthren-17-ol. This nomenclature reveals the presence of multiple chiral centers and functional groups that contribute to the compound's biological activity.

The structural family of this compound encompasses several key functional groups that define its pharmacological properties. The presence of a dimethylamino group attached to a phenyl ring at the 11-position distinguishes this compound from other steroid compounds and contributes significantly to its receptor binding characteristics. The ketone group at position 3 and the hydroxyl group at position 17 are essential for maintaining the steroid backbone's integrity and enabling receptor interactions.

Within the broader classification of selective progesterone receptor modulators, this compound represents a distinct structural subtype characterized by its specific substitution pattern and stereochemical configuration. The compound's relationship to 19-norprogesterone places it within a family of synthetic progestins that have been modified to alter their receptor selectivity and biological activity profiles. This structural heritage provides insight into the rational design principles used to develop selective progesterone receptor modulators with enhanced therapeutic potential.

Historical Development of this compound Compounds

The development of this compound compounds emerged from extensive research into selective progesterone receptor modulators conducted in the late 20th and early 21st centuries. The compound was originally developed as part of collaborative efforts between multiple research institutions, including the National Institutes of Health and various pharmaceutical companies. The initial synthesis and characterization of this compound represented a significant advancement in the field of reproductive endocrinology, building upon earlier work with mifepristone and other first-generation selective progesterone receptor modulators.

Laboratoire Human Reproduction Associates Pharma in France played a pivotal role in the development and refinement of this compound compounds. The company's research efforts focused on creating second-generation selective progesterone receptor modulators with improved selectivity profiles and reduced side effect potential compared to existing compounds. This developmental pathway led to the creation of this compound as a more tolerable alternative to mifepristone, with lower glucocorticoid activity and better binding affinity for progesterone receptors.

The synthetic methodologies for producing this compound have undergone continuous refinement since its initial development. Early synthetic approaches required multiple steps and produced relatively low yields, limiting the compound's availability for research purposes. Subsequent improvements in synthetic chemistry led to more efficient routes for this compound production, including a notable six-step synthesis process that achieved approximately 27.4% total yield, making it more suitable for industrial-scale production.

Research into this compound stereoisomers and related compounds has expanded significantly since the original development. Scientists have identified and characterized multiple stereoisomeric forms of this compound, including 11α,17α-isomer, 11α,17β-isomer, and 11β,17β-isomer variants. These investigations have provided valuable insights into structure-activity relationships and have contributed to a better understanding of how subtle molecular changes can affect biological activity and receptor binding characteristics.

The evolution of this compound synthesis has also focused on identifying and characterizing potential impurities and degradation products. Comprehensive studies have analyzed various stereoisomeric and N,N-didemethylated impurities that may arise during the manufacturing process. These research efforts have been crucial for establishing quality control standards and ensuring the consistency of this compound preparations used in research applications.

This compound vs. This compound Acetate: Molecular Distinctions

The distinction between this compound and this compound acetate represents a fundamental difference in molecular structure that significantly impacts the compounds' chemical and pharmacological properties. This compound acetate is derived from this compound through acetylation of the 17-hydroxy group, resulting in the addition of an acetyl functional group to the parent molecule. This structural modification transforms the molecular formula from $$ \text{C}{28}\text{H}{35}\text{NO}3 $$ for this compound to $$ \text{C}{30}\text{H}{37}\text{NO}4 $$ for this compound acetate, increasing the molecular weight from 433.58 to 475.6 daltons.

The acetylation process involves the conversion of the 17-hydroxy group in this compound to an acetate ester in this compound acetate. This chemical transformation is represented by the attachment of an acetyl group (CH₃CO-) to the hydroxyl oxygen at position 17 of the steroid backbone. The resulting ester linkage creates a prodrug relationship, where this compound acetate serves as a more stable and bioavailable form that can be converted back to the active this compound molecule through metabolic processes.

The structural differences between these compounds extend beyond simple molecular weight considerations to encompass significant changes in chemical stability, solubility, and biological activity. The acetate ester group in this compound acetate provides enhanced chemical stability compared to the free hydroxyl group in this compound, making the acetate derivative more suitable for pharmaceutical formulations and storage. This increased stability results from the protection of the reactive hydroxyl group, which reduces the potential for oxidation and other degradative reactions.

Crystallographic analysis reveals that this compound acetate exhibits a white to yellow crystalline powder appearance, reflecting the impact of the acetyl group on the compound's solid-state properties. The ester modification affects the compound's lipophilicity and membrane permeability characteristics, potentially influencing its distribution and metabolism within biological systems. These physicochemical differences make this compound acetate the preferred form for most research and therapeutic applications, despite this compound being the ultimate active molecular species.