ABSTRACT Chiral imine cages featuring an aromatic cavity are developed employing naphthalene diimide and porphyrin subunits via imine condensation reaction. The structures are characterized by NMR, MALDI‐TOF mass spectrometry, UV–vis and, circular dichroism (CD) spectroscopy. Furthermore, the configuration of one type of the imine cage was confirmed by single‐crystal x‐ray diffraction. Self‐sorting studies were further performed. When different‐sized porphyrin monomers of equal molar amounts and naphthalene diimide ligands are mixed and subjected to self‐assembly reactions, two distinct types of porphyrin imine cages can be obtained. Aromatic guest coronene can be efficiently encapsulated within the imine cages, where coronene engages in supramolecular π–π interactions with the two porphyrin planes. This work constructs complex NDI‐based chiral covalent porphyrin cages using relatively simple precursor units, which are anticipated to find applications in fields like host–guest recognition and catalysis.
ABSTRACT Metabolism is a complex chemical reaction network (CRN) that distributes reaction flux across multiple pathways, and mimicking such routing is of central interest in the design of synthetic out‐of‐equilibrium systems. Here, we investigate a chemically driven transient oligoesterification network in which subtle structural modifications of 4‐hydroxybenzoic acid monomers give rise to markedly different routing behaviors. Strongly electron‐withdrawing substituents positioned ortho to the phenolic hydroxy group act as molecular traffic directors by modulating its nucleophilicity and thereby selectively enabling or suppressing specific reaction channels. This substituent‐guided pathway selection directly links molecular structure to network routing and provides a programmable strategy for wiring synthetic CRNs in ways reminiscent of biological metabolic organization. These findings demonstrate how chemical modification can reconfigure network connectivity and advance the rational design of complex synthetic CRNs.
ABSTRACT This study presents a comprehensive investigation of the switching kinetics of a widely used spiropyran–merocyanine (SP–MC) photoswitch in different solvents. Under UV irradiation, the forward SP→MC conversion follows apparent first‐order kinetics, yielding a mono‐exponential increase in MC population toward a photostationary state (PSS). In contrast, green‐light irradiation and thermal relaxation drive the reverse MC→SP conversion via exponential decay kinetics. These processes must be treated independently, as they originate from distinct photophysical and thermodynamic mechanisms. The proposed rate laws are validated experimentally in different solvent environments. Temperature‐dependent studies reveal that thermal back‐isomerization increasingly shifts the equilibrium toward the SP‐enriched state and can substantially suppress MC formation at elevated temperatures. Solvent polarity strongly influences the forward switching kinetics: while MC formation exhibits ideal monoexponential behavior in a polar solvent such as acetonitrile, decreasing polarity induces pronounced deviations from first‐order behavior due to aggregation phenomena involving the highly polar MC species. In contrast, the reverse MC→SP conversion remains largely monoexponential and insensitive to solvent polarity, consistent with the greater thermodynamic stability of the less polar SP state in nonpolar environments.
ABSTRACT Autocatalysis plays a critical role in the self‐organization of chemical and biological systems, influencing phenomena such as bistability and reaction–diffusion front formation. In the rhizosphere, the regulation of reactive oxygen species (ROS) is mediated by intricate networks of reversible autocatalytic reactions, yet the mechanisms governing their spatiotemporal dynamics remain unclear. Here, we perform comprehensive numerical simulations of a reaction–diffusion model for ROS dynamics incorporating redox couples, sodium borohydride, and oxygen. We identify oxidation‐driven autocatalysis as the primary mechanism responsible for the emergence of stable reaction–diffusion fronts that propagate with constant velocity and shape, whereas reduction fronts display diffusive broadening attenuated by the local oxygen concentration. Furthermore, we demonstrate that reversible quadratic autocatalytic cycles coupled to a simple autocatalyst removal and diffusion are sufficient to reproduce these characteristic front behaviors. These results also provide insights that are transferable to a wide range of autocatalytic networks exhibiting spatiotemporal pattern formation.
ABSTRACT Lipophilic anchors are essential biomolecular modifications that mediate membrane‐dependent functions by tethering associated biomolecules, such as peripheral proteins, to the lipid bilayer. Inspired by natural multi‐lipidation systems, we introduce a DNA origami platform functionalized with lipophilic anchors spanning a wide hydrophobicity range to systematically investigate how anchor hydrophobicity governs membrane binding and lateral organization. By varying anchor type, number, and spatial arrangement, we evaluated the interactions of anchor‐modified DNA origami across homogeneous and phase‐separated giant unilamellar vesicles (GUVs). On homogeneous lipid membranes, stable attachment required a minimum per‐anchor hydrophobicity (cLogP ≈ 5) below which binding of origami to the membrane was ineffective regardless of anchor type or number. However, combining weak and strong anchors on a single nanostructure synergistically enhances binding through cooperative effects that exceed additive contributions of either anchor type. On phase‐separated GUVs, our combined‐anchor system revealed that anchor molecular identity and intrinsic hydrophobicity regulate membrane partitioning. Notably, weak anchors drive the nanostructure localization from the liquid‐ordered (Lo) to the liquid‐disordered (Ld) phase, with this shift inversely related to the hydrophobicity of the strong anchor. Collectively, our results establish design principles for multi‐anchor strategies enabling tunable membrane binding and controlled phase‐specific localization of DNA nanostructures.
