Fast detection of sodium dithionite in sugar using a xanthylium-based fluorescent probe.

Dithionite remained in the foodstuff may pose a great threat to the health of consumers. Three xanthylium-based probes were synthesized and their responses to dithionite were explored. Probe SH-1 could respond to dithionite selectively in PBS buffer (15% DMSO, 10 mM, pH = 7.

Identification of the first selective bioluminescent probe for real-time monitoring of carboxylesterase 2 and .

Carboxylesterase (CES), a main hydrolysis enzyme family in the human body, plays a crucial role in drug metabolism. Among them, CES1 and CES2 are the primary subtypes, and each exhibits distinct distribution and functions. However, convenient and non-invasive methods for distinguishing them and the real-time monitoring of CES2 are relatively rare, hindering the further understanding of physiological functions and underlying mechanisms.

Clinically Translatable Solid-State Dye for NIR-II Imaging of Medical Devices.

Medical devices are commonly implanted underneath the skin, but how to real-time noninvasively monitor their migration, integrity, and biodegradation in human body is still a formidable challenge. Here, the study demonstrates that benzyl violet 4B (BV-4B), a main component in the FDA-approved surgical suture, is found to produce fluorescence signal in the first near-infrared window (NIR-I, 700-900 nm) in polar solutions, whereas BV-4B self-assembles into highly crystalline aggregates upon a formation of ultrasmall nanodots and can emit strong fluorescence in the second near-infrared window (NIR-II, 1000-1700 nm) with a dramatic bathochromic shift in the absorption spectrum of ≈200 nm. Intriguingly, BV-4B-involved suture knots underneath the skin can be facilely monitored during the whole degradation process in vivo, and the rupture of the customized BV-4B-coated silicone catheter is noninvasively diagnosed by NIR-II imaging.

Design, Synthesis, and Bioevaluation of Dexmedetomidine Prodrug.

Dexmedetomidine is commonly used in clinical practice as an anesthetic adjuvant and sedative. Unfortunately, major side effects include significant blood pressure fluctuation and bradycardia. Herein, we report the design and synthesis of four series of dexmedetomidine prodrugs aimed to alleviate hemodynamic fluctuations and simplify the administration procedure.

New ε-N-thioglutaryl-lysine derivatives as SIRT5 inhibitors: Chemical synthesis, kinetic and crystallographic studies.

SIRT5 has been implicated in various physiological processes and human diseases, including cancer. Development of new highly potent, selective SIRT5 inhibitors is still needed to investigate disease-related mechanisms and therapeutic potentials. We here report new ε-N-thioglutaryllysine derivatives, which were designed according to SIRT5-catalysed deacylation reactions.

A fluorescent probe for alkylating agents and its quantification of triflate as a genotoxic impurity.

The responses of a reaction-based fluorescent probe BI-Py towards alkyl halide, epoxide, carbonate, sulfate, sulphonate and triflate were evaluated and the probe achieved selective detection of ethyl triflate in acetonitrile with a LOD of 1.08 μM. BI-Py exhibited great potential for detecting triflate as a genotoxic impurity in drug substances.

A selective and sensitive near-infrared fluorescent probe for real-time detection of Cu(i).

The disruption of copper homeostasis (Cu/Cu) may cause neurodegenerative disorders. Thus, the need for understanding the role of Cu in physiological and pathological processes prompted the development of improved methods of Cu analysis. Herein, a new near-infrared (NIR) fluorescent turn-on probe (NPCu) for the detection of Cu was developed based on a Cu-mediated benzylic ether bond cleavage mechanism.

A Michael addition reaction-based fluorescent probe for malononitrile detection and its applications in aqueous solution, living cells and zebrafish.

It is highly desirable to detect malononitrile in organisms and human bodies owning to its inherent toxicity. With dicyanovinyl as the recognition site, a Michael addition reaction-based fluorescent probe Hcy-DCV was developed for malononitrile detection. A notable advantage of this probe is that it responds quickly to malononitrile without any additive to speed the sensing reaction.

A novel dual-function fluorescent probe for the rapid detection of bisulfite and hydrogen peroxide in aqueous solution and living cells.

In this work, Hcy-OB, a novel hemicyanine-based biocompatible dual-function fluorescence probe for bisulfite and HO detection is designed and synthesized. Based on a 1,4-addition reaction, Hcy-OB can be used for bisulfite detection with fast response, high sensitivity and low detection limit (120 nM). In addition, the probe is successfully applied to the detection of bisulfite in aqueous solution.

A selective and sensitive near-infrared fluorescent probe for in vivo real time tracking of exogenous and metabolized hydrazine, a genotoxic impurity.

Hydrazine is a well-known genotoxic impurity which may be present in some important drugs, such as isoniazid and hydralazine. It may be ingested along with the drug or generated as a metabolite in the human body. Hence, monitoring the level of hydrazine in the human body is of great importance.

Gold Nanoclusters for NIR-II Fluorescence Imaging of Bones.

Fluorescence imaging in the second near-infrared window (NIR-II, 1000-1700 nm) holds great promise for deep tissue visualization. Development of novel clinical translatable NIR-II probes is crucial for realizing the medical applications of NIR-II fluorescence imaging. Herein, the glutathione-capped gold nanoclusters (AuNCs, specifically Au (SG) ) demonstrate highly efficient binding capability to hydroxyapatite in vitro for the first time.

An effective biocompatible fluorescent probe for bisulfite detection in aqueous solution, living cells, and mice.

Sulfur dioxide, an air pollutant, is easily hydrated to sulfites and bisulfites and extremely harmful to human health. On the other hand, endogenous sulfur dioxide is the fourth gasotransmitter. In view of the above, it is worth developing an effective method for the detection of these compounds.

Design, Synthesis, and Activity Study of Water-Soluble, Rapid-Release Propofol Prodrugs.

In this work, a series of water-soluble propofol prodrugs were synthesized, and their propofol release rate and pharmacodynamic characteristics were measured. We found that inserting glycolic acid as a linker between propofol and the cyclic amino acid accelerated the release of propofol from prodrugs into the plasma while preserving its safety. In animal experiments, prodrugs (, , and ) were significantly better than fospropofol (the only water-soluble propofol prodrug that has been used clinically) in terms of safety, onset, and duration time of anesthesia.

Fast Noninvasive Measurement of Brown Adipose Tissue in Living Mice by Near-Infrared Fluorescence and Photoacoustic Imaging.

Aberrant brown adipose tissue (BAT) metabolism is linked to obesity as well as other metabolic disorders. However, the paucity of imaging tools limits the study of in vivo BAT metabolism in animal models. The current work evaluated a heptamethine dye (CyHF-8) in living mice as a dual-modality BAT-avid molecular probe for two imaging approaches, including near-infrared fluorescence imaging (NIRF) and photoacoustic imaging (PAI).

The synthesis and bioimaging of a biocompatible hydrogen sulfide fluorescent probe with high sensitivity and selectivity.

Hydrogen sulfide (HS), a well-known poisonous gas, has been recognized as a critical endogenous gas transmitter in the past decade. To provide a quick and efficient detection method for hydrogen sulfide, a novel fluorescent probe DCI-NCN was designed based on an isophoronitrile scaffold featured with the cyanoxy group as the detection group. DCI-NCN shows promising results including high selectivity, high sensitivity, good linear relationship and pH stability in vitro.

A sensitive and selective fluorescent probe for hydrazine with a unique nonaromatic fluorophore.

To achieve sensitive, selective and facile detection of hydrazine in environmental and biological systems, a fluorescent probe (Che-Dcv) with a unique nonaromatic fluorophore was developed. Upon hydrazine addition in 20% DMSO-PBS buffer (pH = 7.4, 10 mM, v/v) at room temperature, the probe displayed a strong emission at 496 nm along with a color change from brown-red to yellow.

Synthesis and evaluation of pyrazine and quinoxaline fluorophores for in vivo detection of cerebral tau tangles in Alzheimer's models.

A series of pyrazine and quinoxaline probes (QNNs) were synthesized and evaluated. The quinoxaline derivative 3b, with high affinity and selectivity for tau aggregates, favorable fluorescence turn-on capability and brain kinetics, was successfully applied to the detection of tau tangles both in vitro and in mice in vivo.

Synthesis of novel peptide dendrimers PDL-GB2 and PDL-G2.

Peptide dendrimers are a novel type of macromolecules with precise structure, which can be used as drug target vector and controlled-release carrier. So it is valuable to study. In this paper, novel peptide dendrimers PDL-GB2 and PDL-G2 were prepared according to divergent procedure with four-orientation molecule as the core and L-lysine as the branch unit.

Synthesis and characterization of a glycine-modified heptamethine indocyanine dye for in vivo cancer-targeted near-infrared imaging.

Near-infrared (NIR) fluorescent sensors have emerged as promising molecular tools for cancer imaging and detection in living systems. However, cancer NIR fluorescent sensors are very challenging to develop because they are required to exhibit good specificity and low toxicity as an eligible contrast agent. Here, we describe the synthesis of a new heptamethine indocyanine dye (NIR-27) modified with a glycine at the end of each N-alkyl side chain, and its biological characterization for in vivo cancer-targeted NIR imaging.

A multifunctional heptamethine near-infrared dye for cancer theranosis.

Personalized oncology significantly relies on the development of cancer theranostic agents to integrate cancer therapeutics and diagnostics. Current most common strategy for development of such multifunctional agents requires multistep chemical conjugation with cancer targeted ligands, contrast agents and therapeutic agents. Here we report the chemical synthesis and biological characterization of a new heptamethine dye, termed as IR-808DB, natively with multifunctional characteristics of cancer targeting, near-infrared fluorescence imaging, and efficient anticancer activity.

Synthesis and antibacterial activity of new fluoroquinolones containing a cis- or trans-cyclohexane moiety.

New quinolone derivatives bearing a cis- or trans-cyclohexane side chain at the C-7 position have been synthesized and evaluated for their antibacterial activities against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using the agar dilution method. The activities of compound 53 against these three bacteria were superior to those of the reference drug lomefloxacin. Compounds bearing a cis-cyclohexane side chain generally exhibited greater antibacterial activity than their corresponding trans-isomers.

[3-Bromo-meth-yl-1-(4-methyl-phenyl-sulfon-yl)azetidin-3-yl]methanol.

The asymmetric unit of the title compound, C(12)H(16)BrNO(3)S, contains two independent mol-ecules. In each mol-ecule, the azetidine four-membered ring adopts a nearly planar conformation, the maximum deviations being 0.087 (3) and 0.

A general synthetic procedure for 2-chloromethyl-4(3H)-quinazolinone derivatives and their utilization in the preparation of novel anticancer agents with 4-anilinoquinazoline scaffolds.

In our ongoing research on novel anticancer agents with 4-anilinoquinazoline scaffolds, a series of novel 2-chloromethyl-4(3H)-quinazolinones were needed as key intermediates. An improved one-step synthesis of 2-chloromethyl-4(3H)-quinazolinones utilizing o-anthranilic acids as starting materials was described. Based on it, 2-hydroxy-methyl-4(3H)-quinazolinones were conveniently prepared in one pot.

3,3'-[(tert-Butoxy-carbon-yl)aza-nedi-yl]dipropanoic acid.

The title compound, C(11)H(19)NO(6), is an important inter-mediate for the synthesis of cephalosporin derivatives. The N atom is in a planar configuration. In the crystal, mol-ecules are linked into zigzag layers parallel to (100) by O-H⋯O hydrogen bonds.