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Rational modification of molecular structure by incorporating electron donating groups can play a potential role for designing aggregation induced emission (AIE) active fluorescent probes. Based on this principle, fluorescent probes (1a-c) were synthesized, and they displayed excellent aggregation induced emission (AIE) behavior in a H

Stimuli-responsive proteins have gained a wide spread interest as functional biomaterials in drug delivery area. However, particular attention has been diverted to peptide-based materials due to their adaptability and reliable practical utility in biomedical applications under a range of physiological situations. Peptides exhibit a high degree of chemical and biophysical versatility, biocompatibility, and biodegradability compared to other responsive systems. Several peptide motifs have been identified to undergo significant changes in conformation as a result of their response to both internal and external stimuli including light, pH, temperature, enzymes, ionic species and redox reactions. Understanding the structure and functions of peptides both at micro and macro levels is necessary before they can be used as nano devices, as biosensors, in regenerative tissue engineering and in drug delivery. The present review provides an overview of the peptide-based stimuli responsive materials, their design and discussion of their potential setbacks and opportunities for further exploration in drug delivery applications. The design of peptide-based materials of desired architectures, their properties and potential applications will be discussed covering the literature of the past decade, with a focus on their responsiveness to external and internal stimuli.

Innate immune responses to Zika virus (ZIKV) are dampened in the lower female reproductive tract (LFRT) compared to other tissues, but the mechanism that underlies this vulnerability is poorly understood. Using tissues from uninfected and vaginally ZIKV-infected macaques and mice, we show that low basal expression of RNA-sensing pattern recognition receptors (PRRs), or their co-receptors, in the LFRT contributes to high viral replication in this tissue. In the LFRT, ZIKV sensing provides limited protection against viral replication, and the sensors are also minimally induced after vaginal infection. While IFNα/β receptor signaling offers minimal protection in the LFRT, it is required to prevent dissemination of ZIKV to other tissues, including the upper FRT. Our findings support a role for RNA-sensing PRRs in the dampened innate immunity against ZIKV in the LFRT compared to other tissues and underlie potential implications for systemic dissemination upon heterosexual transmission of ZIKV in women., Here, Khan et al. show that enhanced Zika virus replication in the lower female reproductive tract of mice and macaques associates with low expression of RNA sensing pattern recognition receptors, while IFNAR signaling may be critical in preventing viral dissemination to distal tissues.

Contaminated soil and water pose a serious threat to human health and ecosystem. For the treatment of industrial effluents or minimizing their detrimental effects, preventive and remedial approaches must be adopted prior to the occurrence of any severe environmental, health, or safety hazard. Conventional treatment methods of wastewater are insufficient, complicated, and expensive. Therefore, a method that could use environmentally friendly surfactants for the simultaneous removal of both organic and inorganic contaminants from wastewater is deemed a smart approach. Surfactants containing potential donor ligands can coordinate with metal ions, and thus such compounds can be used for the removal of toxic metals and organometallic compounds from aqueous systems. Surfactants form host-guest complexes with the hydrophobic contaminants of water and soil by a mechanism involving the encapsulation of hydrophobes into the self-assembled aggregates (micelles) of surfactants. However, because undefined amounts of surfactants may be released into the aqueous systems, attention must be paid to their own environmental risks as well. Moreover, surfactant remediation methods must be carefully analyzed in the laboratory before field implementation. The use of biosurfactants is the best choice for the removal of water toxins as such surfactants are associated with the characteristics of biodegradability, versatility, recovery, and reuse. This Review is focused on the currently employed surfactant-based soil and wastewater treatment technologies owing to their critical role in the implementation of certain solutions for controlling pollution level, which is necessary to protect human health and ensure the quality standard of the aquatic environment.

Chiral protected monoaryl esters (2a–2h) were synthesized from monoester of l-tartaric acid, having two asymmetric centers and C2 axis of symmetry. l-tartaric acid was protected and partially hydrolyzed to give the corresponding monoester. Monoester upon treatment with different substituted phenols gave desired monoaryl esters (2a–2h). Fries rearrangement of monoaryl esters was then tried under various conditions by using different Lewis acids. All the compounds were purified and characterized by using spectroscopic techniques like IR, 1H-NMR, 13C-NMR, HRMS-ESI, and elemental analysis. The structure of compound 2e was obtained by X-ray crystallography.

The derivatives of anilines are promisingly useful in rechargeable batteries, electrochromics and biosensors. Phenol and aniline based compounds are bestowed with strong antioxidant and anticancer activities. Based on these considerations three new chlorohydroxyanilines (CHAs) were synthesized and characterized by IR, 13C NMR, 1H NMR and UV-Vis spectroscopy. Cyclic, differential pulse and square wave voltammetry were used for the investigations of the electrochemical fate of these compounds in different pH media. Computational chemistry was used as a tool to verify the experimental outcomes. Two chlorohydroxyanilines were found to oxidize at a potential lower than the standard antioxidant, ascorbic acid. The pH dependent oxidation indicated the involvement of protons during electron transfer reactions. The quasi-reversible and irreversible nature of the first and second oxidation peak was evidenced by square wave voltammetry. The slope of peak potential vs. pH plot and the width at half peak height indicated 1e and 1H+ involvement in each oxidation step. Molecular docking and UV-Vis spectroscopy revealed that all chlorohydroxyanilines interact with DNA via an electrostatic binding mode. A sensitive differential pulse technique allowed the determination of a very low limit of detection.

The title compound, C(18)H(21)N(3)O(5), was prepared by the reaction of 3-benzamido-5-nitro-benzyl methane-sulfonate with diethano-lamine and is an inter-mediate in the synthesis of DNA minor-groove-binding polybenzamide agents capable of being conjugated to additional biologically active species. The asymmetric unit contains two independent mol-ecules, which differ only in the orientations of the hydroxy-ethyl groups. In the crystal structure, inter-molecular N-H⋯O and O-H⋯O hydrogen bonds link mol-ecules into one-dimensional chains.

In the title compound, C16H11FO2, a synthetic isocoumarin, the benzene ring is not perpendicular to the planar isocoumarin ring sytem, the dihedral angle being 75.32 (3)°. Inter­molecular C—H⋯O hydrogen bonds may be effective in the stabilization of the crystal structure.

The title compound, C15H8ClFO2, is a chemically synthesized isocoumarin. The isocoumarin and benzene ring systems are approximately perpendicular to each other. The crystal packing is stabilized by C—H⋯O and C—H⋯F inter­­actions to form one-dimensional chains parallel to the b axis.

The title compound, C16H11O2ClF, is a chemically synthesized isocoumarin. The mol­ecule is not planar and the dihedral angle between the isocoumarin and benzene ring systems is 42.43 (6)°. The structure is stabilized by C—H⋯O and C—H⋯F inter­molecular inter­actions, forming a one-dimensional chain parallel to the b axis and stacking down the a axis by π–π inter­actions.

The title compound, C15H11FO2, is a derivative of α-phenyl­cinnamic acid. The two benzene rings in the mol­ecule are approximately perpendicular to each other. O—H⋯O hydrogen bonding occurs between mol­ecules.

In the title compound, C16H11ClO2, an unnaturally occurring isocoumarin, the benzene ring is nearly perpendicular to the planar isocoumarin ring system. The crystal packing is stabilized by intra- and intermolecular C—H...Cl and C—H...O hydrogen bonds.

The title compound, C(15)H(24)N(2)O(4)Si, was prepared by the reaction of (3-acetamido-5-nitro-benz-yl)methanol with tert-butyl-dimethyl-silyl chloride and is a key inter-mediate in the synthesis of novel nonsymmetrical DNA minor groove-binding agents. There are two independent mol-ecules in the structure, which differ primarily in the rotation about the C-O bond next to the Si atom. Two strong N-H⋯O hydrogen bonds align the mol-ecules into a wide ribbon extending approximately parallel to the b axis.

The title compound, C8H8N2O7S, an intermediate in the synthesis of N,N-bis(2-hydroxyethyl)-3,5-dinitroaniline, exists as a discrete molecule; the nitro groups are twisted with respect to the aromatic system [dihedral angles = 17.0 (1) and 26.3 (1)°].

The title compound, C(11)H(15)N(3)O(6), was prepared by the reaction of (3,5-dinitro-benz-yl)methane-sulfonate with diethanol-amine. The asymmetric unit contains four crystallographically independent mol-ecules which differ primarily in their rotation about the bond between the aromatic ring and the N-diethanol unit. The mol-ecules are linked into sheets by a hydrogen-bonding network which involves all of the hydroxy groups, with only van der Waals contacts between the sheets.

The title compound, C11H12N2O5, was prepared by the reaction of 3-amino-5-nitro­benzyl alcohol with acetic anhydride. The asymmetric unit contains three independent mol­ecules which differ in geometry only by their rotation about the single bonds external to the benzene ring. The title compound is an inter­mediate in the synthesis of DNA minor-groove-binding polybenzamide agents.

The title compound, C9H10N2O4·C2H6OS, was prepared by the selective hydrolysis of 3-acetamido-5-nitro­benzyl ­acetate with sodium hydroxide in ethanol. The crystal structure contains a dimethyl sulfoxide solvent mol­ecule. The title compound is an inter­mediate in the synthesis of DNA minor-groove-binding polybenzamide agents. N—H⋯O and O—H⋯O hydrogen bonds are present in the crystal structure.