The main C(1) isomer of C(70)F(38) is shown by single-crystal X-ray analysis to contain four planar aromatic hexagons and four isolated C=C bonds, has two fluorines on the equator, and is related to C(2) C(70)F(38) by means of three 1,3-fluorine shifts. The C(1) and C(2) isomers thus parallel the T and C(3)/C(1) isomers of C(60)F(36) in containing three and four aromatic rings, respectively, and in the fluorine shift relationship.
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http://dx.doi.org/10.1021/ol050441t | DOI Listing |
J Chem Theory Comput
January 2025
Department of Chemistry, Birla Institute of Technology Mesra, Ranchi 835215, India.
Planar hexacoordination is an extremely uncommon phenomenon for the atoms that belong to the main group. Within this article, we have analyzed the potential energy surfaces (PES) of ABeCB (A = N, P, As, Sb, and Bi) clusters in neutral, monocationic, monoanionic, dicationic, and dianionic states using density functional theory (DFT). Among which PBeCB, PBeCB, AsBeCB, AsBeCB, SbBeCB, and BiBeCB clusters contain a planar hexacoordinate boron (phB) atom in the global minimum energy structures with symmetry.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
Aromaticity is one of the most classical concepts in the field of modern chemistry and has been employed to explain and design substances with special stability. Although the knowledge about Hückel's and Baird's rules has been well established, the understanding of Möbius aromaticity remains extremely limited. In this letter, by employing density functional theory (DFT) calculations, we demonstrated that the four-membered VIB transition metal (TM) carbide clusters possess a highly stable open-shell planar tetrameric structure and exhibit double Möbius aromaticity, which was evidenced by analyzing multiple aromaticity criteria, including the electronic, magnetic, and energetic indicators.
View Article and Find Full Text PDFBioorg Chem
December 2024
Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Medicinal Chemistry, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address:
In this study, novel 2-styrylquinoline derivatives possessing a planar aromatic system and a flexible side chain with an amino substituent were designed and synthesized as DNA-intercalating antitumor agents. The cytotoxic activity of the synthesized compounds was evaluated against four cancer cell lines including MCF-7 (breast cancer cells), A549 (lung epithelial cancer cells), HCT116 (colon cancer cells) and normal cell line L929 (mouse fibroblast cell line). The results displayed that the anti-cancer activity of the target quinolines is sensitive to the lipophilic nature of the C-6 and C-7 quinoline substituents.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry, University of California, Berkeley, California 94720, United States.
Developing multicharge and spin stabilization strategies is fundamental to enhancing the lifetime of functional organic materials, particularly for long-term energy storage in multiredox organic redox flow batteries. Current approaches are limited to the incorporation of electronic substituents to increase or decrease the overall electron density or bulky substituents to sterically shield reactive sites. With the aim to further expand the molecular toolbox for charge and spin stabilization, we introduce regioisomerism as a scaffold-diversifying design element that considers the collective and cumulative electronic and steric contributions from all of the substituents based on their relative regioisomeric arrangements.
View Article and Find Full Text PDFOrg Lett
January 2025
State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences (CAS), CAS, Shanghai 200032, China.
Rearrangement of the skeleton is crucial for improving the structural complexity and diversity of type II polyketide natural products. In this study, we investigated the rearrangement process from a planar aromatic tetracyclic intermediate to the caged lactones, which is managed by five oxidoreductases. We chemically synthesized the proposed linear tetracyclic substrate, validated the transformation process through and experiments, and elucidated the enzyme-catalyzed mechanism using isotope labeling.
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