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1. 1,3-Asymmetric Induction in Diastereoselective Allylations of Chiral N -Tosyl Imines

   https://doi.org/10.1021/acs.joc.1c02691  

   Lo, Anna; Gutierrez, David A.; Toth-Williams, Garrett; Fettinger, James C.; Shaw, Jared T. (March 2022, The Journal of Organic Chemistry)
2. Diastereoselective Addition of Prochiral Nucleophilic Alkenes to α-Chiral N -Sulfonyl Imines

   https://doi.org/10.1021/acs.orglett.1c04219  

   Gutierrez, David A.; Fettinger, James; Houk, K. N.; Ando, Kaori; Shaw, Jared T. (February 2022, Organic Letters)
3. Chiral self-sorting of active semiflexible filaments with intrinsic curvature

   https://doi.org/10.1039/D0SM01163K  

   Moore, Jeffrey M.; Glaser, Matthew A.; Betterton, Meredith D. (January 2021, Soft Matter)

   null (Ed.)

   Many-body interactions in systems of active matter can cause particles to move collectively and self-organize into dynamic structures with long-range order. In cells, the self-assembly of cytoskeletal filaments is critical for cellular motility, structure, intracellular transport, and division. Semiflexible cytoskeletal filaments driven by polymerization or motor-protein interactions on a two-dimensional substrate, such as the cell cortex, can induce filament bending and curvature leading to interesting collective behavior. For example, the bacterial cell-division filament FtsZ is known to have intrinsic curvature that causes it to self-organize into rings and vortices, and recent experiments reconstituting the collective motion of microtubules driven by motor proteins on a surface have observed chiral symmetry breaking of the collective behavior due to motor-induced curvature of the filaments. Previous work on the self-organization of driven filament systems have not studied the effects of curvature and filament structure on collective behavior. In this work, we present Brownian dynamics simulation results of driven semiflexible filaments with intrinsic curvature and investigate how the interplay between filament rigidity and radius of curvature can tune the self-organization behavior in homochiral systems and heterochiral mixtures. We find a curvature-induced reorganization from polar flocks to self-sorted chiral clusters, which is modified by filament flexibility. This transition changes filament transport from ballistic to diffusive at long timescales. 

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4. Au-Cavitand Catalyzed Alkyne-Acid Cyclizations: Au-Cavitand Catalyzed Alkyne-Acid Cyclizations

   https://doi.org/10.1002/ejoc.201900829  

   Ho, Tam D.; Schramm, Michael P. (September 2019, European Journal of Organic Chemistry)
5. Curvature‐Assisted Vesicle Explosion Under Light‐Induced Asymmetric Oxidation

   https://doi.org/10.1002/advs.202400504  

   Malik, Vinit_Kumar; Pak, On_Shun; Feng, Jie (August 2024, Advanced Science)

   Abstract Exposure of cell membranes to reactive oxygen species can cause oxidation of membrane lipids. Oxidized lipids undergo drastic conformational changes, compromising the mechanical integrity of the membrane and causing cell death. For giant unilamellar vesicles, a classic cell mimetic system, a range of mechanical responses under oxidative assault has been observed including formation of nanopores, transient micron‐sized pores, and total sudden catastrophic collapse (i.e., explosion). However, the physical mechanism regarding how lipid oxidation causes vesicles to explode remains elusive. Here, with light‐induced asymmetric oxidation experiments, the role of spontaneous curvature on vesicle instability and its link to the conformational changes of oxidized lipid products is systematically investigated. A comprehensive membrane model is proposed for pore‐opening dynamics incorporating spontaneous curvature and membrane curling, which captures the experimental observations well. The kinetics of lipid oxidation are further characterized and how light‐induced asymmetric oxidation generates spontaneous curvature in a non‐monotonic temporal manner is rationalized. Using the framework, a phase diagram with an analytical criterion to predict transient pore formation or catastrophic vesicle collapse is provided. The work can shed light on understanding biomembrane stability under oxidative assault and strategizing release dynamics of vesicle‐based drug delivery systems. 

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