Yong-Hoon Kwon

The first total synthesis of the potent antibiotic disciformycin B (2) is described, which is exceptionally isomerization-prone and transforms into disciformycin A (1) even under notably mild conditions. To outweigh this bias, the approach to 2 hinged on the use of a silyl residue at C4 to lock the critical double bond in place and hence insure the integrity of the synthetic intermediates en route to 2. This tactic was instrumental for the preparation of the building blocks and formation of the

InternAl delivery: Organoaluminum reagents activate 1,4-dien-3-ones for Nazarov electrocyclization (see scheme), then transfer a substituent to the resulting cyclopentenyl cation with moderate to complete regioselectivity and diastereoselectivity.

Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease characterized by selective death of motor neurons. Mutations in Cu, Zn-superoxide dismutase (SOD1) causing the gain of its toxic property are the major culprit of familial ALS (fALS). The abnormal SOD1 aggregation in the motor neurons has been suggested as the major pathological hallmark of ALS patients. However, the development of pharmacological interventions against SOD1 still needs further investigation. In this study,

A domino potassium permanganate-interrupted Nazarov reaction to yield syn-2,3-disubstituted 1,4-diketones via a decarbonylative cleavage of the Nazarov oxyallyl intermediate, believed to be without precedent, is presented. This process allows syn substituents to be established stereospecifically on the 2-carbon bridge connecting the ketone carbonyl carbons, and the formation of one carbon-carbon and two carbon-oxygen bonds. Two carbon-carbon bonds are cleaved in this process.

Trimethylaluminum and molecular oxygen are used in tandem to interrupt the Nazarov cyclization. α-Hydroxycyclopentanones are produced in moderate to good yield as a mixture of epimers. This sequence is the first example of combined nucleophilic/electrophilic trapping of the Nazarov oxyallyl intermediate.

The first synthesis of micrococcin P2 has been achieved by late-stage Suzuki coupling of a macrocyclic boronic acid with a 2-bromothiazole.

Al gibt Cp den Rest: Organoaluminiumreagentien aktivieren 1,4-Dien-3-one für eine Nazarov-Elektrocyclisierung (siehe Schema) und übertragen anschließend einen Substituenten auf die resultierenden Cyclopentenylkationen. Der Prozess verläuft mit mäßiger bis vollständiger Regio- und Diastereoselektivität. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are

Abstract A domino potassium permanganate‐interrupted Nazarov reaction to yield syn‐2,3‐disubstituted 1,4‐diketones via a decarbonylative cleavage of the Nazarov oxyallyl intermediate, believed to be without precedent, is presented. This process allows syn substituents to be established stereospecifically on the 2‐carbon bridge connecting the ketone carbonyl carbons, and the formation of one carbon–carbon and two carbon–oxygen bonds. Two carbon–carbon bonds are cleaved in this process.

Abstract Natural products decursin and decursinol angelate were recently reported as benign fungicides for controlling rice blast. Inspired by the structural similarity of the cumarin compounds and gained hint from the skeletal motifs, we designed and prepared synthetic compounds to increase the natural product efficacy and evaluated their antifungal activities against various plant disease pathogens in vitro. Synthetically prepared compound 4 and 5 indeed suppressed the mycelial growth of B. ci

Micrococcin P1 and P2 are thiopeptides with a wide range of biological functions including antibacterial and antimalarial activities. We previously demonstrated optimized enzymatic sequences for the exclusive and scalable biosynthesis of micrococcin P2. Thiocillin IV is predicted to be the congener of O -methylated micrococcin P2, but the exact structure has not been elucidated. In this study, we report the first scalable biosynthesis and full structural characterization of thiocillin IV, a 26-m

Abstract The escalating demand for effective and sustainable weed management strategies, driven by urbanization expansion, is a critical challenge. Herbicides are pivotal tools in modern agriculture, addressing this challenge. Developing novel herbicides with enhanced efficacy and minimal environmental impact is crucial for food security and ecological balance. While numerous herbicides have been developed with varying availability over time and regions, there's a continuous need for innovation.

Aryl vinyl ketones, particularly those lacking an α-substituent, are among the most challenging substrates for Nazarov cyclization. We present a practical method to expand the scope of this reaction, enabling the efficient synthesis of indanones and bicyclic 2-pyrones. The use of an α-silyl substituent as a "structural dummy" enhances reactivity, and thus, the reaction proceeds under mild conditions. Notably, spontaneous desilylation during the reaction leaves the products with double-enolizable

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Abstract A quick and convenient synthetic method to produce α‐hydroxycyclopentanones with three bond forming events via one‐pot interrupted Nazarov cyclization/oxidation using trimethylaluminum and triplet oxygen is described.