- Twofold π-Extension of Polyarenes via Double and Triple Radical Alkyne peri-Annulations: Radical Cascades Converging on the Same Aromatic Core
-
A versatile synthetic route to distannyl-substituted polyarenes was developed via double radical peri-annulations. The cyclization precursors were equipped with propargylic OMe traceless directing groups (TDGs) for regioselective Sn-radical attack at the triple bonds. The two peri-annulations converge at a variety of polycyclic cores to yield expanded difunctionalized polycyclic aromatic hydrocarbons (PAHs). This approach can be extended to triple peri-annulations, where annulations are coupled with a radical cascade that connects two preexisting aromatic cores via a formal C-H activation step. The installed Bu3Sn groups serve as chemical handles for further functionalization via direct cross-coupling, iodination, or protodestannylation and increase solubility of the products in organic solvents. Photophysical studies reveal that the Bu3Sn-substituted PAHs are moderately fluorescent, and their protodestannylation results in an up to 10-fold fluorescence quantum yield enhancement. DFT calculations identified the most likely possible mechanism of this complex chemical transformation involving two independent peri-cyclizations at the central core.
- Gonzalez-Rodriguez, Edgar,Abdo, Miguel A.,Dos Passos Gomes, Gabriel,Ayad, Suliman,White, Frankie D.,Tsvetkov, Nikolay P.,Hanson, Kenneth,Alabugin, Igor V.
-
-
Read Online
- Design, synthesis, and biological characterization of a new class of symmetrical polyamine-based small molecule CXCR4 antagonists
-
CXCR4, a well-studied coreceptor of human immunodeficiency virus type 1 (HIV-1) entry, recognizes its cognate ligand SDF-1α (also named CXCL12) which plays many important roles, including regulating immune cells, controlling hematopoietic stem cells, and directing cancer cells migration. These pleiotropic roles make CXCR4 an attractive target to mitigate human disorders. Here a new class of symmetrical polyamines was designed and synthesized as potential small molecule CXCR4 antagonists. Among them, a representative compound 21 (namely HF50731) showed strong CXCR4 binding affinity (mean IC50 = 19.8 nM) in the CXCR4 competitive binding assay. Furthermore, compound 21 significantly inhibited SDF-1α-induced calcium mobilization and cell migration, and blocked HIV-1 infection via antagonizing CXCR4 coreceptor function. The structure-activity relationship analysis, site-directed mutagenesis, and molecular docking were conducted to further elucidate the binding mode of compound 21, suggesting that compound 21 could primarily occupy the minor subpocket of CXCR4 and partially bind in the major subpocket by interacting with residues W94, D97, D171, and E288. Our studies provide not only new insights for the fragment-based design of small molecule CXCR4 antagonists for clinical applications, but also a new and effective molecular probe for CXCR4-targeting biological studies.
- An, Jing,Fang, Xiong,Huang, Lina S.,Huang, Ziwei,Liang, Boqiang,Meng, Qian,Schooley, Robert T.,Wang, Juan,Xu, Yan,Zhang, Chaozai,Zhang, Huijun,Zhang, Xingquan,Zhu, Siyu
-
-
- POLYMERISABLE COMPOUNDS AND THE USE THEREOF IN LIQUID-CRYSTAL MEDIA AND LIQUID-CRYSTAL DISPLAYS
-
The present invention relates to polymerisable compounds, to processes and intermediates for the preparation thereof, to the use thereof for optical, electro-optical and electronic purposes, in particular in liquid-crystal (LC) media and LC displays havin
- -
-
Paragraph 0403; 0404
(2016/06/28)
-
- POLYMERISABLE COMPOUNDS AND THE USE THEREOF IN LIQUID-CRYSTAL MEDIA AND LIQUID-CRYSTAL DISPLAYS
-
The present invention relates to polymerisable compounds, to processes and intermediates for the preparation thereof, to the use thereof for optical, electro-optical and electronic purposes, in particular in liquid-crystal (LC) media and LC displays havin
- -
-
-