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We report a novel glycan array architecture that binds the mannose-specific glycan binding protein, concanavalin A (ConA), with sub-femtomolar avidity. A new radical photopolymerization developed specifically for this application combines the grafted-from thiol-(meth)acrylate polymerization with thiol-ene chemistry to graft glycans to the growing polymer brushes. The propagation of the brushes was studied by carrying out this grafted-to/grafted-from radical photopolymerization (GTGFRP) at >400 different conditions using hypersurface photolithography, a printing strategy that substantially accelerates reaction discovery and optimization on surfaces. The effect of brush height and the grafting density of mannosides on the binding of ConA to the brushes was studied systematically, and we found that multivalent and cooperative binding account for the unprecedented sensitivity of the GTGFRP brushes. This study further demonstrates the ease with which new chemistry can be tailored for an application as a result of the advantages of hypersurface photolithography.

Vegetables supply various minerals, vitamins, dietary fibers along with important phytochemicals that plays a major contribution in our balance diets and nutrition. Each vegetable contain a unique amount of various nutrients that are strongly linked with the protection of different health diseases. Eggplant (Solanum melongena L.) is a nonwoody annual plant with purple to white flowers along with enlarged lobed leaves with bushy foliage that grows with maximum height of 120cm. Eggplant is mainly grown for vegetables and medicinal purposes. The phytochemical analysis of eggplant shows that it is the rich source of various essential compounds aspartic acid, tropane, flavonoids, lanosterol, gramisterol, steroid alkaloids, glycoalkaloids, histidine, nasunin, oxalic acid, solasodine, ascorbic acid and tryptophan that are present in fruits and leaves. It also contains low calories and high moisture contents. These compounds were found helpful in the cure of various diseases like cancer, anti-inflammatory, anti-asthmatic, anti-platelet hypo-lipidemic, and hypotensive etc. Today most modern scientific techniques are available to cure different various health problems but still majority of population across the globe depends upon the traditional herbal medicines and practices. This review mainly explains nutritional content, medicinal and health benefits of S. melongena

Synthetic carbohydrate receptors (SCRs) that selectively recognize cell-surface glycans could be used for detection, drug delivery, or as therapeutics. Here we report the synthesis of seven new C2h symmetric tetrapodal SCRs. The structures of these SCRs possess a conserved biaryl core, and they vary in the four heterocyclic binding groups that are linked to the biaryl core via secondary amines. Supramolecular association between these SCRs and five biologically relevant C1 -O-octyloxy glycans, α/s-glucoside (α/s-Glc), α/s-mannoside (α/s-Man), and s-galactoside (s-Gal), was studied by mass spectrometry, 1 H NMR titrations, and molecular modeling. These studies revealed that selectivity can be achieved in these tetrapodal SCRs by varying the heterocyclic binding group. We found that SCR017 (3-pyrrole), SCR021 (3-pyridine), and SCR022 (2-phenol) bind only to s-Glc. SCR019 (3-indole) binds only to s-Man. SCR020 (2-pyridine) binds s-Man and α-Man with a preference to the latter. SCR018 (2-indole) binds α-Man and s-Gal with a preference to the former. The glycan guests bound within their SCR hosts in one of three supramolecular geometries: center-parallel, center-perpendicular, and off-center. Many host-guest combinations formed higher stoichiometry complexes, 2:1 glycan⋅SCR or 1:2 glycan⋅SCR, where the former are driven by positive allosteric cooperativity induced by glycan-glycan contacts.

Synthetic carbohydrate receptors could serve as agents for disease detection, drug delivery, or even therapeutics, however, they are rarely used for these applications because they bind weakly and with a preference towards the all-equatorial glucosides that are not prevalent on the cell surface. Herein the binding of 8 receptors with 5 distinct octyloxy pyranosides, which was measured by mass spectrometry and by 1 H NMR titrations in CD2 Cl2 at 298 K, is reported, providing binding affinities that vary from ≈101 -104 m-1 . Although the receptors are promiscuous, 1 shows selectivity for β-Man at a ratio of 103:1 β-Man:β-Gal, receptors 2-4 and 6 have preference for α-Man, 5 is selective for β-Gal, and 10 prefers α-Glc (Man=mannose; Gal=galactose, Glc=glucose). A variety of 1D and 2D NMR, and computational techniques were used to determine the thermodynamic binding parameters (ΔHo and ΔSo ) and the structure of the host-guest complex, revealing that dimeric receptor 10 binds β-Man with increased enthalpy, but a larger entropic penalty than 1. The first-principles modelling suggests that 10⋅β-Man forms an inclusion-type complex where the glycan engages both monomeric subunits of 10 through H-bonding and C-H⋅⋅⋅π interactions. Like natural glycan-binding proteins, these receptors bind pyranosides by accessing multivalent and cooperative interactions, and these studies suggest a new approach towards biomimetic synthetic carbohydrate receptors, where conformational flexibility and promiscuity are incorporated into design.