Facile and general synthesis of quaternary 3-aminooxindoles

A novel approach to the valuable quaternary 3-aminooxindole skeleton is reported on the basis of intramolecular arylation of enolates of substituted amino acids. The reaction tolerates dialkyl- and arylalkylamines as well as a range of carbon substituents (primary and secondary alkyl, aryl). The cyclization of N-indolyl-substituted substrates is accompanied by direct C-H arylation of the indole, leading to indolo-fused benzodiazepines.     

Fiber Integrated Metal-Organic Frameworks as Functional Components in Smart Textiles

Owing to high modularity and synthetic tunability, metal–organic frameworks (MOFs) on textiles are poised to contribute to the development of state-of-the-art wearable systems with multifunctional performance. While these composite materials have demonstrated promising functions in sensing, filtration, detoxification, and biomedicine, their applicability in multifunctional systems is only beginning to materialize. This review highlights the multifunctionality and versatility of MOF-integrated textile systems. It summarizes the operational goals of MOF@textile composites, encompassing sensing, filtration, detoxification, drug delivery, UV protection, and photocatalysis. Building upon these recent advances, this review concludes with an outlook on emerging opportunities for the diverse applications of MOF@textile systems in the realm of smart wearables.     

Crystal structures and physico-chemical properties of Zn(II) and Co(II) tetraaqua(3-nitro-4-hydroxybenzoato) complexes: Their anticonvulsant activities as well as related (5-nitrosalicylato)–metal complexes

Purposes of these studies were to synthesize Zn(II) and Co(II) complexes of 3-nitro-4-hydroxybenzoic acid, determine their structures through X-ray crystallography, and obtain their anticonvulsant activities. Thermogravimetric, differential scanning calorimetry, impedance of aqueous solutions and magnetic properties analyses were also determined. Anticonvulsant and related activities of these complexes as well as Zn(II), Co(II), Ni(II) and Mg(II) (5-nitrosalicylato) complexes were determined by the National Institutes of Health, Antiepileptic Development Program. Results of these analyses are presented to document unique bonding features and physical properties of these compounds and their anticonvulsant activities. It is concluded that these compounds have chemical and physical properties that can be used to account for their anticonvulsant activities.     

Transport processes in responding lipid membranes: a possible mechanism for the pH gradient in the stratum corneum

The "acidic mantle" of the skin surface has been related to several essential functions of the skin, although the origin of the acidity is still obscure. In this paper, we investigate how different transport processes can influence the local proton concentration inside a membrane consisting of oriented lipid bilayers. This system is chosen as a simple model of the extracellular lipids in the upper layer of the skin, the stratum corneum. We present a theoretical model for diffusional transport over the membrane in the presence of an osmotic gradient and a gradient in CO(2), taking into account the influence of these gradients on the lipid structure and the local electrostatics. We are also discussing the complications in applying the concept of pH to the stratum corneum. From this, we make the following conclusions: (i) The definition of pH in the stratum corneum is ambiguous, and thus, all statements regarding pH should always be related to a clear definition. (ii) A natural definition of pH in the stratum corneum can be proposed which takes into account local heterogeneity, local charges, and the fact that the stratum corneum is not in thermodynamical equilibrium. (iii) Diffusive transport across an oriented bilayer stack in the presence of an osmotic gradient and/or a gradient in CO(2) can give rise to a substantial gradient in pH. (iv) The results from the simplified model can be correlated to experimental observations of pH in the stratum corneum.     

Towards quantitatively reproducible substrates for SERS

There is a need for a method to facilitate the development of novel, reproducible colloidal surface-enhanced Raman scattering (SERS) substrates to encourage the use of SERS in applied studies. In this study we show for the first time that by using suitably designed SERS experiments in conjunction with multivariate analysis of variance (MANOVA), an objective assessment of colloidal SERS reproducibility can be made. This is demonstrated with the analyte cresyl violet, but could be extended to any analyte of interest for which reproducible SERS data are needed.     

Genetic, genomic and physiological state studies on single-needle bio-electrosprayed human cells

Bio-electrospraying, a non-contact jet-based direct cell engineering approach, was recently pioneered and demonstrated for handling a wide range of primary living cells. In those studies, post-treated cells were biologically assessed in comparison to several controls by way of flow cytometry. Although flow cytometry accurately assesses those viable populations of cells, subtle effects at a sub-cellular level could have been missed. Therefore, in the present study we demonstrate metaphase chromosome breakage studies carried out on single-needle bio-electrosprayed human T-lymphocytes, which are compared with several controls. The results indicate that post-treated T-lymphocytes do not demonstrate any increase in chromosome damage in comparison to control cells. These studies further validate bio-electrospraying as a technique with potential for clinical utility.     

Nickel‐Catalyzed Esterification of Aliphatic Amides

Recent studies have demonstrated that amides can be used in nickel‐catalyzed reactions that lead to cleavage of the amide C?N bond, with formation of a C?C or C?heteroatom bond. However, the general scope of these methodologies has been restricted to amides where the carbonyl is directly attached to an arene or heteroarene. We now report the nickel‐catalyzed esterification of amides derived from aliphatic carboxylic acids. The transformation requires only a slight excess of the alcohol nucleophile and is tolerant of heterocycles, substrates with epimerizable stereocenters, and sterically congested coupling partners. Moreover, a series of amide competition experiments establish selectivity principles that will aid future synthetic design. These studies overcome a critical limitation of current Ni‐catalyzed amide couplings and are expected to further stimulate the use of amides as synthetic building blocks in C?N bond cleavage processes.     

Neoglycopeptide dendrimer libraries as a source of lectin binding ligands

[structure: see text] A 15 625-membered peptide dendrimer combinatorial library was acylated with an alpha-C-fucosyl residue at its four N-termini and screened for binding to fucose-specific lectins. Dendrimer FD2 (Fuc-alpha-CH2CO-Lys-Pro-Leu)4(Lys-Phe-Lys-Ile)2Lys-His-Ile-NH2 was identified as a potent ligand against Ulex europaeus lectin UEA-I (IC50 = 11 microM) and Pseudomonas aeruginosa lectin PA-IIL (IC50 = 0.14 microM).