SuFEx (Sulfur-Fluoride Exchange) Chemistry represents the next-generation approach to covalent drug discovery, chemical biology, and synthetic chemistry. Building on the principles of click chemistry, SuFEx reactions leverage the unique S(VI)–F bond, allowing precise and high-yielding chemical transformations under mild conditions.

OTAVA, in collaboration with Melius Organics, introduces a comprehensive SuFEx Handle Fragment Library, a diverse collection of aryl fluorosulfates and sulfamoyl fluorides designed to expand the druggable proteome, enhance covalent drug development, and facilitate advanced chemical synthesis.

Why SuFEx Chemistry?

SuFEx handles serve as key electrophilic fragments in modern drug discovery and synthetic chemistry, offering:

✔ Selective Covalent Bonding – While covalent bonding typically focuses on cysteine, this approach expands selectivity to lysine, tyrosine and histidine.
✔ Superior Stability – Compatible with biological environments, stable in plasma, microsomes, and hepatocytes.
✔ Broad Nucleophile Compatibility – Reacting with amines, alcohols, and carbon-based nucleophiles.
✔ Efficient & Safe Fluoride Leaving Group – Ensuring low toxicity at millimolar (mM) concentrations.
✔ High-Yielding, Click-Like Reactions – Enabling robust functionalization with minimal purification.

Key Applications

Our SuFEx Handle Fragment Library provides a powerful platform for:

✔ Covalent Drug Discovery – Optimized warhead fragments for irreversible enzyme inhibition.
✔ Chemical Proteomics & Enzyme Profiling – Mapping drug-target interactions with precision.
✔ Bioconjugation & Synthetic Biology – Enabling protein crosslinking, peptide conjugation, and bioorthogonal labeling.
✔ Synthetic Chemistry & Late-Stage Functionalization – Enhancing lead optimization and library expansion.

Expanding the Drug Discovery Landscape

The SuFEx Handle Fragment Library features 74,543 fluorosulfate and sulfamoyl fluoride fragments, with:
✔ Virtual Screening Readiness – Computational docking for structure-based drug design.
✔ Rapid Physical Synthesis & Delivery – Fragments available within 3 weeks.
✔ Seamless Integration into Drug Discovery Pipelines – Direct transition from in silico hits to experimental testing.

Proven Biochemical Activity

SuFEx-based molecules have demonstrated potent inhibitory activity against various biological targets:

✔ Pan-IAP Inhibitor (J. Med. Chem. 2019, 62, 9188) – IC₅₀ = 38 nM
✔ HIV-1 Reverse Transcriptase Inhibitor (ACS Med. Chem. Lett. 2021, 12, 249) – IC₅₀ = 103 nM
✔ Soluble Epoxide Hydrolase (sEH) Inhibitor (WO 2015/188060, Scripps Research) – IC₅₀ = 1.4 nM

These studies highlight the expanding potential of SuFEx chemistry in precision drug targeting.

Aryl Fluorosulfates & Sulfamoyl Fluorides – Unparalleled Synthetic Chemistry Advantages

SuFEx handle fragments provide key advantages over traditional electrophiles like sulfonyl chlorides, offering:

✔ High Chemoselectivity & Biocompatibility – Targeting specific nucleophiles without off-target reactions.
✔ Late-Stage Functionalization – Ideal for modifying lead compounds and fine-tuning drug properties.
✔ Exceptional Thermodynamic Stability – Resistant to hydrolysis and reduction, ensuring longer shelf life.
✔ Fast & High-Yielding Reactions – Efficient amine, alcohol, and thiol coupling in aqueous environments.

These electrophilic handles enable the synthesis of highly functionalized molecules, making them indispensable for drug discovery, materials science, and chemical biology.

Partner with OTAVA & Melius Organics

✔ All starting materials in stock – Ensuring immediate availability for synthesis.
✔ Global Delivery & Rapid Turnaround – Physical samples ready within 3 weeks.
✔ Expert Support – Helping you integrate SuFEx chemistry into your research and drug development efforts.

 Contact Us Today:
 ⇒  This e-mail address is being protected from spambots. You need JavaScript enabled to view it (OTAVA)

• DOWNLOAD: SuFEx handle fragment library brochure (PDF)

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