Synthesis of Sulfonamides in the Biobased Solvent Cyrene

ChemistryOpen, 2026

An alternative and efficient protocol for sulfonamide synthesis using the biobased solvent Cyrene is reported. A broad range of amines reacts smoothly with sulfonyl chlorides at room temperature, furnishing 20 sulfonamides in moderate to high yields within 30–60 min. Products are isolated by simple precipitation without chromatography, while Cyrene can be recovered (up to 79%) and reused without loss of performance.

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Stereodefined Synthesis of 3-Difluoromethyl-Benzoxaboroles: Novel Antimicrobials with Unlocked H-Bonding

Organic letters, 2026

Benzoxaboroles, prominent scaffolds in medicinal chemistry, are typically modified on the benzene ring. In contrast, functionalization of the oxaborol ring is less common and often challenging. Indeed, 3-hydroxy-benzoxaboroles are virtually impossible to isolate due to their tautomeric equilibrium with the carbonyl form. In this work, we introduce a novel class of stereodefined 3-difluoromethyl-benzoxaboroles. The replacement of the hydroxy group with −CHF₂ preserves stability while promoting bioactivity, owing to the lipophilic H-bond donor properties of the latter. Find out more here.

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Photochemical C4-Selective C–H Amination of Quinolines via N-Shift of Heteroaryl Azides

Organic letters, 2026

We report a photochemical strategy enabling the direct synthesis of 3,4-diaminoazines through C3-to-C4 nitrogen migration (N-shift). Blue LED irradiation of 3-azidoquinolines at room temperature allows C4-selective C–H amination while concurrently installing diverse amines at the C3–position. In contrast, N-shifts in 3-azidopyridines preferentially form diazepines, reflecting divergent reactivity governed by N-heterocycle electronics, as supported by computational analysis.

Safracin B as a Synthetic Linchpin: From Natural Product to Drug Intermediate and Beyond

Eur. J. Org. Chem., 2026

The reactivity of safracin B is investigated as a platform for the efficient synthesis of cyanosafracin B and safracin A, with particular emphasis on the optimization of reaction conditions to achieve high yield and purity. In addition, a complete assignment of the nuclear magnetic resonance spectra of these structurally complex members of the safracin family is reported. Overall, this study deepens the understanding of structure–reactivity relationships within safracin natural products and highlights their value as versatile scaffolds for synthetic, analytical, and medicinal chemistry applications.

Synthesis of α-fluorocinnamate derivatives as novel cathepsin S inhibitors with in vitro antiproliferative activity against pancreatic cancer cells

Bioorg. Med. Chem., 2025
We have designed and synthesized three new derivatives basing on an isosteric replacement (H–F) at the level of cinnamate moiety. These derivatives emerged as potent covalent inhibitors of CatS (1.8–2.6 µM) with 2F showing also weak inhibition activity against CatL (20 %) and CatB (29 %). In vitro assays of 2F against pancreatic cancer cell lines BXPC3 and CAPAN1 revealed significant antiproliferative activity, with IC₅₀ = 5.79 µM and 20.75 µM, respectively. To find out more details follow the page

Metal-Free, Selective Ortho-Deuteration of N-Heterocyclic Oxides

Adv. Synth. Cat., 2025
In this work, we present a metal-free, selective ortho-deuteration of N-heterocycles starting from their N-oxides, proceeding at room temperature in just 5 minutes. More about it at this link

Design, synthesis and in vitro validation of bivalent binders of SARS-CoV-2 spike protein: Obeticholic, betulinic and glycyrrhetinic acids as building blocks

Bioorg. Med. Chem., 2025
Bivalent compounds have been designed to simultaneously bind both pockets of the Spike protein, offering significant advantages over single molecules or the combination of the two natural products. In vitro cell assays using pseudotyped recombinant lentiviral particles with selected SARS-CoV-2 Spike proteins demonstrated that 1 and 2 exhibit enhanced activity in reducing viral entry into target cells compared to individual natural products. Check it out at this link