(S,R,S)-AHPC-PEG1-NH2 dihydrochloride

Background Introduction

(S,R,S)-AHPC-PEG1-NH2 dihydrochloride is a specially designed E3 ligase ligand-linker conjugate tailored for targeted protein degradation research. As a building block for PROTAC (Proteolysis Targeting Chimera) synthesis, this molecule features the von Hippel-Lindau (VHL) ligand (AHPC) coupled to an amino-terminated polyethylene glycol (PEG1) linker, presented in its dihydrochloride salt form to enhance solubility and stability. This unique structure allows researchers to efficiently couple the ligand to various protein-targeting moieties, facilitating custom PROTAC development for chemical biology and drug discovery applications.

Mechanism

The mechanism of (S,R,S)-AHPC-PEG1-NH2 dihydrochloride centers on its role as a modular E3 ligase recruiting unit in PROTAC design. The AHPC fragment specifically binds to the VHL E3 ubiquitin ligase complex, while the PEG1 linker enables flexible attachment to a ligand for the protein of interest. When assembled into a complete PROTAC molecule, the VHL-recruiting AHPC moiety brings the E3 ligase into close proximity with the target protein. This proximity promotes ubiquitination and subsequent proteasomal degradation of the target. The NH2 terminus of the linker provides convenient chemical functionality for conjugation to a variety of warheads or protein binding modules.

Applications

(S,R,S)-AHPC-PEG1-NH2 dihydrochloride is widely applied in the design and synthesis of PROTACs for both basic research and drug discovery. Its primary use is as an E3 ligase recruiting element, allowing researchers to target disease-relevant proteins for degradation via the ubiquitin-proteasome system. This conjugate is ideal for rapid structure-activity relationship (SAR) studies, exploration of novel protein degradation targets, and development of next-generation therapeutics for cancer, neurodegenerative diseases, and autoimmune conditions. The ready-to-use PEG1 linker enhances solubility and cellular permeability, making it a versatile platform for chemical biology, medicinal chemistry, and targeted protein degradation studies.

• Versatile PEG1 linker increases solubility and flexibility in PROTAC design, enabling more efficient protein degradation.
• Amine-terminated structure allows straightforward conjugation to diverse warheads, streamlining von Hippel-Lindau (VHL)-based PROTAC synthesis.

The (S,R,S)-AHPC-PEG1-NH2 dihydrochloride serves as a versatile E3 Ligase Ligand-Linker Conjugate in PROTACs, facilitating targeted protein degradation by bridging E3 ligases with target proteins. This molecule's design enhances the specificity and efficacy of protein degradation, making it a valuable tool for researchers exploring targeted therapies and protein function studies.

Linker: The PEG1 linker in this molecule is a short, flexible polyethylene glycol unit, providing optimal spacing between the ligand and the reactive site. Its flexibility facilitates efficient binding and can be tailored for cleavability depending on the experimental requirements.

Ligand: The ligand component of this molecule is based on the AHPC structure, known for its high affinity and specificity towards cereblon, an E3 ubiquitin ligase. This structural characteristic allows for effective recruitment of the ligase to the target protein, enhancing degradation efficiency.

Reactive Site: The reactive site of (S,R,S)-AHPC-PEG1-NH2 is the terminal amine group, which is suitable for coupling with various electrophilic groups on the target protein ligand. Recommended reaction types include amide bond formation and reductive amination, offering robust and stable conjugation.

Recommended Target Protein Ligand: The ideal warhead for this conjugate is a small molecule with a reactive electrophilic moiety, such as a carbonyl or sulfonyl chloride group. These warheads facilitate effective covalent binding with the reactive site, promoting efficient degradation of the target protein. This conjugate is particularly suited for applications in studying protein-protein interactions and identifying novel therapeutic targets.