Estrone-N-O-C1-amido

Target: This ligand targets estrogen receptors ERα/ESR1 and ERβ/ESR2 in biochemical or cellular target-engagement studies.

Mechanism of Action: Used as the target-protein recognition element, this ligand provides the binding interface for estrogen receptors ERα/ESR1 and ERβ/ESR2. In PROTAC design, a derivatizable position on the ligand can be connected through an optimized linker to an E3 ligase ligand, such as a CRBN, VHL, or IAP recruiter, while preserving productive target engagement. The resulting bifunctional molecule brings estrogen receptors ERα/ESR1 into proximity with the recruited E3 ligase, enabling ternary-complex formation. If the complex has favorable geometry and residence time, target lysine ubiquitination is promoted, leading to proteasome-dependent degradation in experimental systems.

• PROTAC-Mediated Estrogen Receptor Degradation: Estrone-N-O-C1-amido can serve as a steroidal binding ligand in PROTAC architectures to recruit an E3 ligase and drive ubiquitination-dependent degradation of estrogen receptor targets. This enables systematic evaluation of how ligand positioning and linker length influence ternary complex formation, proteasome engagement, and degradation potency in cellular assays.

• E3 Ligase Recruitment Optimization: The ligand can be incorporated into PROTAC designs to probe E3 ligase selection and recruitment efficiency. By varying the attachment site and linker chemistry, researchers can assess changes in ubiquitin transfer kinetics and overall target turnover, supporting rational optimization of degradation strength over simple occupancy-based inhibition.

• Linker and Geometry Structure–Activity Studies: Estrone-N-O-C1-amido-based PROTACs are suitable for structure–activity relationship studies that map how linker length, flexibility, and stereochemical orientation affect productive ternary complex assembly. These experiments help identify configurations that maximize target proximity to the E3 ligase, thereby enhancing ubiquitination and downstream proteolysis.

• Mechanistic Studies of Ubiquitin–Proteasome Pathways: Using this ligand in targeted degradation workflows allows investigation of degradation mechanisms, including dependence on ubiquitination and proteasomal activity. Researchers can employ pathway perturbations to confirm that observed loss of target protein arises from PROTAC-driven proteolysis rather than transcriptional or translational effects, strengthening mechanistic interpretation.

Estrone-N-O-C1-amido is an estrogen receptor ligand derivative suitable for ER-targeted PROTAC research. Its modified steroidal framework provides a linker-oriented amide-containing vector.

Structure: Estrone-N-O-C1-amido is an estrone-derived ER ligand bearing a steroidal phenolic core and an oxime/O-linked acetamide-type substituent at the 17-ketone-derived region. The molecule retains the phenolic hydroxyl and introduces an amide handle through the oxime linkage.

Reactivity: This ER ligand is already modified at the estrone ketone vector and can be used as an ER-targeting building block for PROTAC design. The amide-containing side chain can support extension through amide, alkyl, or PEG linker analogs to CRBN, VHL, or IAP ligands while preserving the steroid core and phenolic hydroxyl. The oxime linkage and linker length should be checked for stability and ER-binding tolerance.