Structural and Electronic Determinants Underlying the Biofunctional Profile of Isothiocyanates: A Structure-activity...

Area of Science:

• Medicinal Chemistry
• Biochemistry
• Pharmacology

Background:

• Isothiocyanates (ITCs) are electrophilic compounds from cruciferous vegetables with diverse biological activities.
• Their reactivity stems from the -N=C=S moiety, enabling covalent interactions with nucleophiles.
• Side-chain modifications critically impact ITC physicochemical properties, reactivity, and efficacy.

Purpose of the Study:

• To comprehensively review the structure-activity relationships (SAR) of isothiocyanates.
• To elucidate how functional group variations govern ITC bioactivity.
• To integrate mechanistic and pharmacological evidence for SAR annotation.

Main Methods:

• Extensive literature exploration of various ITC classes (alkyl, aromatic, halogenated, etc.).
• Electrophilicity index analyses and comparative evaluation of biological assays.
• Proteomic data and Nrf2-Keap1 signaling pathway studies for mechanistic mapping.

Main Results:

• Electron-withdrawing and oxidized substituents enhance ITC electrophilicity and potency.
• Optimal, non-linear correlations observed between chain length/lipophilicity and activity.
• Aromatic systems increase stability; stereochemistry influences enantioselective differences (e.g., sulforaphane).

Conclusions:

• ITC bioefficacy depends on a balance of electronic effects and molecular geometry.
• SAR-guided design, covalent proteomics, and in vivo validation are crucial for developing ITC therapeutics.
• Understanding ITC SAR can accelerate the rational development of novel therapeutic agents.