SARS-CoV‑2メインプロテアーゼ阻害剤の抗ウイルスプロファイルに対する単一ハロゲン原子置換の影響
Haydar Bulut1, Nobuyo Higashi-Kuwata2, Hiromi Ogata-Aoki2,3
1Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, NIH, Bethesda, Maryland 20892, United States.
Abstract:
The SARS-CoV-2 main protease (Mpro) remains a prime antiviral target because its inhibition halts viral replication. To probe how subtle atomic changes influence drug performance, we carried out a systematic halogen scan on a potent ketoamide scaffold, replacing a single fluorine with chlorine, bromine, or iodine. Enzymatic assays revealed that the F- and Cl-substituted analogues inhibit Mpro at nanomolar levels, whereas Br and I variants are 10- to 20-fold weaker. Cell-based antiviral tests mirrored this trend, yet uptake studies showed the opposite: iodine markedly enhances intracellular accumulation. High-resolution X-ray structures (1.6-1.8 Å) explain the dichotomy: small halogens fit snugly in the S1' σ-hole pocket, maximizing hydrogen-bond geometry, while bulkier atoms distort binding but create a lipophilic patch that boosts permeability. These data yield the first fluorine-to-iodine structure-activity map for SARS-CoV-2 Mpro inhibitors. These findings highlight the critical role of halogen selection in antiviral inhibitor design.
関連する概念動画
Halogens
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Radical Substitution: Halogenation of Alkanes and Alkyl Substituents
In the initiation step of the reaction, the chlorine molecule undergoes homolytic cleavage in the presence of light or heat, forming two highly reactive chlorine radicals. Propagation occurs in two...
Atomic Structure
Atomic Mass
Atomic Orbitals


