The modular synthesis of 7 libraries containing 51 self-assembling amphiphilic Janus dendrimers with the monosaccharides D-mannose and D-galactose and the disaccharide D-lactose in their hydrophilic part is reported. These unprecedented sugar-containing dendrimers are named amphiphilic Janus glycodendrimers. Their self-assembly by simple injection of THF or ethanol solution into water or buffer and by hydration was analyzed by a combination of methods including dynamic light scattering, confocal microscopy, cryogenic transmission electron microscopy, Fourier transform analysis, and micropipet-aspiration experiments to assess mechanical properties. These libraries revealed a diversity of hard and soft assemblies, including unilamellar spherical, polygonal, and tubular vesicles denoted glycodendrimersomes, aggregates of Janus glycodendrimers and rodlike micelles named glycodendrimer aggregates and glycodendrimermicelles, cubosomes denoted glycodendrimercubosomes, and solid lamellae. These assemblies are stable over time in water and in buffer, exhibit narrow molecular-weight distribution, and display dimensions that are programmable by the concentration of the solution from which they are injected. This study elaborated the molecular principles leading to single-type soft glycodendrimersomes assembled from amphiphilic Janus glycodendrimers. The multivalency of glycodendrimersomes with different sizes and their ligand bioactivity were demonstrated by selective agglutination with a diversity of sugar-binding protein receptors such as the plant lectins concanavalin A and the highly toxic mistletoe Viscum album L. agglutinin, the bacterial lectin PA-IL from Pseudomonas aeruginosa, and, of special biomedical relevance, human adhesion/growth-regulatory galectin-3 and galectin-4. These results demonstrated the candidacy of glycodendrimersomes as new mimics of biological membranes with programmable glycan ligand presentations, as supramolecular lectin blockers, vaccines, and targeted delivery devices.

This tutorial review summarizes strategies elaborated for the discovery and prediction of programmed primary structures derived from quasi-equivalent constitutional isomeric libraries of self-assembling dendrons, dendrimers and dendronized polymers. These libraries demonstrate an 82% predictability, defined as the percentage of similar primary structures resulting in at least one conserved supramolecular shape with internal order. A combination of structural and retrostructural analysis that employs methodologies transplanted from structural biology, adapted to giant supramolecular assemblies was used for this process. A periodic table database of programmed primary structures was elaborated and used to facilitate the emergence of a diversity of functions in complex dendrimer systems via first principles. Assemblies generated by supramolecular and covalent polymer backbones were critically compared. Although by definition complex functional systems cannot be designed, this tutorial hints to a methodology based on database analysis principles to facilitate design principles that may help to mediate an accelerated emergence of chemical, physical and most probably also societal, political and economic complex systems on a shorter time scale and lower cost than by the current methods. This tutorial review is limited to the simplest, synthetically most accessible self-assembling minidendrons, minidendrimers and polymers dendronized with minidendrons that are best analyzed and elucidated at molecular, supramolecular and theoretical levels, and most used in other laboratories. These structures are all interrelated, and their principles expand in a simple way to their higher generations.

An accelerated modular synthesis produced 18 amphiphilic Janus glycodendrimers with three different topologies formed from either two or one carbohydrate head groups or a mixed constellation with a noncarbohydrate hydrophilic arm. By simple injection of their THF solutions into water or buffer, all of the Janus compounds self-assembled into uniform, stable, and soft unilamellar vesicles, denoted glycodendrimersomes. The mixed constellation topology glycodendrimersomes were demonstrated to be most efficient in binding plant, bacterial, and human lectins. This evidence with biomedically relevant receptors offers a promising perspective for the application of such glycodendrimersomes in targeted drug delivery, vaccines, and other areas of nanomedicine.

A library of eight amphiphilic Janus glycodendrimers (GDs) with D-mannose (Man) headgroups, a known routing signal for lectinmediated transport processes, was constructed via an iterative modular methodology. Sequence-defined variations of the Janus GD modulate the surface density and sequence of Man after selfassembly into multilamellar glycodendrimersomes (GDSs). The spatial mode of Man presentation is decisive for formation of either unilamellar or onion-like GDS vesicles. Man presentation and Janus GD concentration determine GDS size and number of bilayers. Beyond vesicle architecture, Man topological display affects kinetics and plateau level of GDS aggregation by a tetravalent model lectin: the leguminous agglutinin Con A, which is structurally related to endogenous cargo transporters. The agglutination process was rapid, efficient, and readily reversible for onion-like GDSs, demonstrating their value as versatile tools to explore the nature of physiologically relevant glycan/lectin pairing.self-assembly | synthetic multilamellar vesicles | glycolipid mimics S upramolecular chemistry has enormous potential to help resolve fundamental questions in the realm of cell biology. One of the key challenges is the design of programmable models for vesicles and cells and their surfaces as a means of establishing a chemical platform that mimics natural features in size and shape, and also allows customized implementation of bioactive epitopes, in structural and topological terms. Natural complexity can conveniently be reduced to simple systems, whose degree of diversity can then be rationally reconstituted in a stepwise process. Focusing on surface properties, the recently gained access to uniform populations of stable glycodendrimersomes (GDSs) by a simple injection method using a solution of amphiphilic Janus glycodendrimers (GDs) as building blocks for self-assembly in a water-soluble aprotic solvent (1-3), has afforded a promising opportunity to realize this concept. Interestingly, the resulting GDSs, which have tunable surface features, can cover the size range of naturally occurring vesicles such as endo-and exosomes.

Two-dimensional (2D) ferromagnetic semiconductors (FMSs) exhibit novel spin-dependent electronic and optical properties, opening up exciting opportunities for nanoscale spintronic devices.

A library of eight amphiphilic Janus glycodendrimers (Janus-GDs) presenting D-lactose (Lac) and a combination of Lac with up to eight methoxytriethoxy (3EO) units in a sequence-defined arrangement was synthesized via an iterative modular methodology. The length of the linker between Lac and the hydrophobic part of the Janus-GDs was also varied. Self-assembly by injection from THF solution into phosphate-buffered saline led to unilamellar, monodisperse glycodendrimersomes (GDSs) with dimensions predicted by Janus-GD concentration. These GDSs provided a toolbox to measure bioactivity profiles in agglutination assays with sugar-binding proteins (lectins). Three naturally occurring forms of the human adhesion/growth-regulatory lectin galectin-8, Gal-8S and Gal-8L, which differ by the length of linker connecting their two active domains, and a single amino acid mutant (F19Y), were used as probes to study activity and sensor capacity. Unpredictably, the sequence of Lac on the Janus-GDs was demonstrated to determine bioactivity, with the highest level revealed for a Janus-GD with six 3EO groups and one Lac. A further increase in Lac density was invariably accompanied by a substantial decrease in agglutination, whereas a decrease in Lac density resulted in similar or lower bioactivity and sensor capacity. Both changes in topology of Lac presentation of the GDSs and seemingly subtle alterations in protein structure resulted in different levels of bioactivity, demonstrating the presence of regulation on both GDS surface and lectin. These results illustrate the applicability of Janus-GDs to dissect structure-activity relationships between programmable cell surface models and human lectins in a highly sensitive and physiologically relevant manner.

Electrocatalytic N2 reduction is one of the most promising ways for green and sustainable production of NH3. However, a mechanistic understanding of the N2 reduction process remains very limited. Herein, a surface-hydrogenation mechanism for the N2 reduction reaction is proposed, which can well address the recently emerged sharp discrepancies between experiments and computations. Our results reveal that surface hydrogenation can drive N2 reduction reaction on catalysts with weak N2-binding strength (i.e., noble-metal catalysts) at low potentials. Instead of N2 adsorption, the reduction of H+ is found to be the first step, which is also the potential determining step of the whole process. N2 can be activated and reduced into *N2H2 subsequently by overcoming relatively high energy barriers, which determines the total reaction rate. Moreover, the cooperative effect of surface *H and the catalysts plays a key role in the activation of N2. Our work not only provides new insights into the N2 reduction reaction, but also paves a promising way for advancing sustainable NH3 production.

Two-dimensional (2D) ferromagnetic semiconductors (FMSs) are desirable for their potential to enhance the functionality of semiconductor devices via the utilization of spin degrees of freedom. Herein, we predict a series of intrinsic FMS monolayers in the chromium sulfide halide CrSX (X = Cl, Br, I) family with large spin polarization, large magnetic moments and high Curie temperatures. Such CrSCl and CrSBr monolayers also have high hole mobilities up to 6.6 × 103 and 5.3 × 103 cm2 V-1 s-1, respectively. Furthermore, these 2D monolayers exhibit excellent dynamic and thermal stabilities and a small exfoliation energy from the bulk. These intrinsic FMSs with their high mobilities may provide competitive candidates for next-generation spintronics and electronics.