We are MedChem: The Frontiers in Medicinal Chemistry 2024.

The Frontiers in Medicinal Chemistry (FiMC) is the largest international Medicinal Chemistry conference in Germany and took place from March 17 to 20 2024 in Munich. Co-organized by the Division of Medicinal Chemistry of the German Chemical Society (Gesellschaft Deutscher Chemiker; GDCh) and the Division of Pharmaceutical and Medicinal Chemistry of the German Pharmaceutical Society (Deutsche Pharmazeutische Gesellschaft; DPhG), and supported by a local organizing committee from the Ludwigs-Maximilians-University Munich headed by Daniel Merk, the meeting brought together approximately 225 participants from 20 countries. The outstanding program of the four-day conference included 40 lectures by leading scientists from industry and academia as well as early career investigators.

Probing the Origin of Affinity in the GM1-Cholera Toxin Complex through Site-Selective Editing with Fluorine.

Carbohydrates regulate an inimitable spectrum of biological functions, yet successfully leveraging this therapeutic avenue continues to be frustrated by low affinities with glycan-specific proteins. A conspicuous exception is the interaction of monosialotetrahexosylganglioside (GM1) with the carbohydrate-recognition domain of cholera toxin from : this is one of the strongest protein-carbohydrate interactions known. To establish the importance of a long-discussed key hydrogen bond between C2 of the terminal galactose of GM1 and the B subunit pentamer of cholera toxin (CTB), the total synthesis of a selectively fluorinated GM1 epitope was conducted in 19 steps.

Back in Person: Frontiers in Medicinal Chemistry 2023.

The Frontiers in Medicinal Chemistry (FiMC) is the largest international Medicinal Chemistry conference in the German speaking area and took place from April 3 to 5 2023 in Vienna (Austria). Fortunately, after being cancelled in 2020 and two years (2021-2022) of entirely virtual meetings, due to the COVID-19 pandemic, the FiMC could be held in a face-to-face format again. Organized by the Division of Medicinal Chemistry of the German Chemical Society (GDCh), the Division of Pharmaceutical and Medicinal Chemistry of the German Pharmaceutical Society (DPhG), together with the Division of Medicinal Chemistry of the Austrian Chemical Society (GÖCH), the Austrian Pharmaceutical Society (ÖPhG), and a local organization committee from the University of Vienna headed by Thierry Langer, the meeting brought together 260 participants from 21 countries.

Application of Lithiation-Borylation to the Total Synthesis of (-)-Rakicidin F.

The stereochemistry of the lipophilic side chain of (+)-rakicidin F had not been determined until recently. Using our lithiation-borylation methodology ("assembly line synthesis") we were able to efficiently prepare the all-syn isomer as well as the C-21 epimer of the side chain, and comparison with the natural product suggested that the natural product had all-syn stereochemistry. Completion of the total synthesis using a macrolactamization of the northern amide enabled us to confirm Wang and Chen's stereochemical findings for the structure of (+)-rakicidin F.

Photocatalytic → Isomerization of β-Ionyl Derivatives.

An operationally simple → isomerization of activated dienes, based on the β-ionyl motif intrinsic to retinal, is reported using inexpensive (-)-riboflavin (vitamin B) under irradiation at 402 nm. Selective energy transfer from photoexcited (-)-riboflavin to the starting -isomer enables geometrical isomerization. Since the analogous process with the -isomer is inefficient, microscopic reversibility is circumvented, thereby enabling a directional isomerization to generate the -thermodynamic product (up to 99% yield, up to 99:1 /).

Catalytic Generation and Chemoselective Transfer of Nucleophilic Hydrides from Dihydrogen.

Copper(I)-N-heterocyclic-carbene (NHC) complexes enabled the catalytic generation of nucleophilic hydrides from dihydrogen (H ) and their subsequent transfer to allylic chlorides. The highly chemoselective catalyst displayed no concomitant hydrogenation reactivity; in fact, the terminal double bond formed in the hydride transfer remained intact. Switching to deuterium gas (D ) allowed for regioselective monodeuteration with excellent isotope incorporation.

Copper(i)-catalysed transfer hydrogenations with ammonia borane.

Highly Z-selective alkyne transfer semihydrogenations and conjugate transfer hydrogenations of enoates can be effected by employing a readily available and air-stable copper(i)/N-heterocyclic carbene (NHC) complex, [IPrCuOH]. As an easy to handle and potentially recyclable H source, ammonia borane (HNBH) is used.

Copper(I)-Catalyzed Allylic Substitutions with a Hydride Nucleophile.

An easily accessible copper(I)/N-heterocyclic carbene (NHC) complex enables a regioselective hydride transfer to allylic bromides, an allylic reduction. The resulting aryl- and alkyl-substituted branched α-olefins, which are valuable building blocks for synthesis, are obtained in good yields and regioselectivity. A commercially available silane, (TMSO)2Si(Me)H, is employed as hydride source.

Z-Selective Copper(I)-Catalyzed Alkyne Semihydrogenation with Tethered Cu-Alkoxide Complexes.

A highly stereoselective alkyne semihydrogenation with copper(I) complexes is reported. Copper-N-heterocyclic carbene complex catalysts, bearing an intramolecular Cu-O bond, allow for the direct transfer of both hydrogen atoms from dihydrogen to the alkyne. The corresponding alkenes can be isolated with high Z selectivity and negligible overreduction to the alkane.