Among stimulus-responsive molecular ring-on-thread rotaxanes and pseudorotaxanes, variants incorporating photochromic sub-units are attracting considerable attention as their properties and structure can be remotely and precisely controlled, additionally without producing chemical waste. The focus herein is on photoswitching-driven assembly/disassembly and modulation of properties resulting from light-activated isomerization or changes in electronic properties.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1039/c9pp00057g | DOI Listing |
J Am Chem Soc
January 2025
Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Transition-metal-catalyzed enantioselective C-H activation has transformed the landscape of asymmetric synthesis, enabling the efficient conversion of C-H bonds into C-C and carbon-heteroatom (C-X) bonds. However, the formation of C-S bonds through enantioselective C-H thiolation remains underdeveloped due to challenges such as catalyst deactivation and competitive coordination of sulfur-containing compounds with chiral ligands. Herein, we report an unprecedented approach to constructing sulfur-substituted planar chiral ferrocenes (PCFs) through copper-mediated enantioselective C-H thiolation enabled by only a 2.
View Article and Find Full Text PDFChempluschem
January 2025
University of Wroclaw: Uniwersytet Wroclawski, Chemistry, 14 F. Joliot-Curie 14, 50383, Wroclaw, POLAND.
The skeletal editing approach represents a paradigm shift in organic synthesis by directly targeting the molecular skeleton instead of relying on often long and complicated series of organic transformations. Recent advancements in nitrogen atom deletion reactions have enabled unprecedented late-stage, precise modifications of bioactive compounds and complex natural products, influencing a seemingly distant field such as supramolecular chemistry. In a recent contribution, the Leigh group demonstrated the extrusion of a nitrogen atom from an axle of a [2]rotaxane, extending the applicability of molecular editing to complex, mechanically interlocked architectures.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
College of Chemistry and Molecular Sciences, Henan University, Kaifeng, 475004, China.
Cycloparaphenylenes (CPPs) represent a significant challenge for the synthesis of mechanically interlocked architectures, because they lack heteroatoms, which precludes traditional active and passive template methods. To circumvent this problem and explore the fundamental and functional properties of CPP rotaxanes and catenanes, researchers have resorted to unusual non-covalent and even to labor-intensive covalent template approaches. Herein, we report a ring-in-ring non-covalent template strategy that makes use of the surprisingly strong non-covalent inclusion of crown ethers into suitably sized CPPs.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing, Shanghai Jiao Tong University, Shanghai, 200240, P. R. China.
Covalent adaptable networks (CANs), a novel class of crosslinked polymers with dynamic covalent bonds, have gained significant attention for combining the durability of thermosets with the reprocessability of thermoplastics, making them promising for emerging applications. Here, we report the first example of poly[2]rotaxane-type covalent adaptable networks (CANs), in which oligo[2]rotaxane backbones characterized by densely packed mechanical bonds, are cross-linked through dynamic C-N bonds. The oligo[2]rotaxane backbones could guarantee the mechanical properties of the CANs.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Institute of Biomedical Engineering, Jinan University, Guangzhou 510632, China. Electronic address:
Hyperuricemia-related diabetic wounds are notoriously difficult to treat due to elevated uric acid (UA) levels, excessive reactive oxygen species (ROS), and chronic inflammation. Current therapies often fail to address these underlying causes, underscoring the need for innovative approaches that not only clear UA but also mitigate inflammation and promote tissue regeneration. In this study, we developed a polyrotaxane-based microsphere (HPR MS) system conjugated with 4,5-diamino-2-thiouracil (DT) to achieve high-affinity UA clearance without increasing cytotoxicity.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!