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CELL imaging, CHARGE exchange, FLUORESCENT probes, DETECTION limit, and NAPHTHALIMIDES

A novel naphthalimides‐based fluorescent probe (NPHD) selectively detected Cu2+ and PPi through "strong yellow‐weak green‐strong yellow" photonic response in a sequential manner. The formation of NPHD‐Cu2+ resulted in obvious fluorescence decreased and wavelength shift from 595 nm to 525 nm by adding Cu2+ to NPHD solution. The mechanism could be attributed to d→π* electron transfer (ET) from Cu2+ to NPHD. Furthermore, the NPHD‐Cu2+ complex exhibited high selectivity toward PPi through via emission recovery of chemosensor NPHD. The detection limits of NPHD to Cu2+ and NPHD‐Cu2+ to PPi were estimated to be 5.72×108M and 2.39×108M. In addition, NPHD could be employed to detect exogenous Cu2+ and PPi in Hep G2 cells. [ABSTRACT FROM AUTHOR]

MOLECULAR self-assembly, NAPHTHALIMIDES, SEMICONDUCTOR manufacturing, SURFACE chemistry, SUPRAMOLECULAR chemistry, HYDROGELS, and AMMONIUM sulfate

Using natural processes as a guiding tool, the scientific community is actively involved in achieving substantial advances at the interface of supramolecular chemistry and materials design. In this paper, we have synthesized a series of amphiphilic N-glycosyl naphthalimides using environmentally benign protocols in good yields. For the first time, an exclusive formation of β-anomeric product using ammonium sulfate catalyst, an FDA approved GRAS chemical, has been thoroughly investigated. To explore the potential of N-glycosyl naphthalimides in the field of supramolecular materials, molecular self-assembly studies were systematically performed in a wide range of solvents and they were found to form a hydrogel, organogel and oleogel. The existence of molecular level interactions and assembly pattern were identified using FT-IR, NMR, SAXRD, UV-vis and fluorescence spectral methods and a suitable assembly mechanism was proposed. The morphology of the supramolecular architecture with respect to the molecular structure was identified using optical microscopy and scanning electron microscopy. Rheological studies clearly disclose the strength of soft materials and processability. Conductivity measurements on assembled thin films developed by drop casting of N-glycosyl naphthalimides reveal the semiconducting behaviour. Interestingly, a highly flexible semiconducting material derived by anchoring of a gelator on cotton fabric through hydrogen bonding displayed enhanced conducting properties compared to the assembled thin film. The demonstrated flexible organic semiconducting material obtained via a more sustainable pathway would provide an opportunity to fabricate green electronics. [ABSTRACT FROM AUTHOR]

FLUORESCENT probes, STOKES shift, PHOTODYNAMIC therapy, NAPHTHALIMIDES, and THERAPEUTICS

The discovery of a near-infrared (NIR, 650–900 nm) fluorescent chromophore hemicyanine dye with high structural tailorability is of great significance in the field of detection, bioimaging, and medical therapeutic applications. It exhibits many outstanding advantages including absorption and emission in the NIR region, tunable spectral properties, high photostability as well as a large Stokes shift. These properties are superior to those of conventional fluorogens, such as coumarin, fluorescein, naphthalimides, rhodamine, and cyanine. Researchers have made remarkable progress in developing activity-based multifunctional fluorescent probes based on hemicyanine skeletons for monitoring vital biomolecules in living systems through the output of fluorescence/photoacoustic signals, and integration of diagnosis and treatment of diseases using chemotherapy or photothermal/photodynamic therapy or combination therapy. These achievements prompted researchers to develop more smart fluorescent probes using a hemicyanine fluorogen as a template. In this review, we begin by describing the brief history of the discovery of hemicyanine dyes, synthetic approaches, and design strategies for activity-based functional fluorescent probes. Then, many selected hemicyanine-based probes that can detect ions, small biomolecules, overexpressed enzymes and diagnostic reagents for diseases are systematically highlighted. Finally, potential drawbacks and the outlook for future investigation and clinical medicine transformation of hemicyanine-based activatable functional probes are also discussed. [ABSTRACT FROM AUTHOR]

HYDRAZIDES, HYDRAZINES, BENZYL halides, HYDRAZINE derivatives, ALDEHYDES, and HYDRAZINE

A new route to synthesis of various mono‐N‐substituted hydrazines and hydrazides by involving in a new C−N bond formation by using N‐amino‐1,8‐naphthalimide as a regenerated precursor was invented. Aniline and phenylhydrazines are reproduced upon reacting these individually with 1,8‐naphthalic anhydride followed by hydrazinolysis. The practicality and simplicity of this C−N dihalo alkanes; developed a synthon for bond formation protocol was exemplified to various hydrazines and hydrazides. N‐amino‐1,8‐naphthalimide is suitable synthon for transformation for selective formation of mono‐substituted hydrazine and hydrazide derivatives. Those are selective mono‐amidation of hydrazine with acid halides; mono‐N‐substituted hydrazones from aldehydes; synthesis of N‐aminoazacycloalkanes from acetohydrazide scaffold and inserted to hydroxy derivatives; distinct synthesis of N,N‐dibenzylhydrazines and N‐benzylhydrazines from benzyl halides; synthesis of N‐amino‐amino acids from α‐halo esters. Ecofriendly reagent N‐amino‐1,8‐naphthalimide was regenerated with good yields by the hydrazinolysis in all procedures. [ABSTRACT FROM AUTHOR]