301668-92-8

Upstream product

• 6959-48-4 3-chloromethylpyridinium chloride 
• 62-53-3 aniline 
• 1203669-57-1 bis-pyridin-2-ylmethyl-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-phenyl]-amine 
• 586-98-1 2-Hydroxymethylpyridine 
• 591-50-4 iodobenzene 
• 1539-42-0 bis[(2-pyridyl)methyl]amine 
• 6959-47-3 2-chloromethylpyridine hydrochloride 
• 4377-33-7 2-chloromethylpyridine 

Downstream Products

• 498534-44-4 dichlorido(N,N-bis(2-pyridylmethyl)benzeneamine)copper(II) 
• 1221742-50-2 N,N’-di-[2-pyridylmethyl]-4-nitroaniline 
• 946005-73-8 4-(N,N-di-(pyridine-2-ylmethyl)amino)benzaldehyde 

Relevant academic research and scientific papers

A selective triarylmethine-based spectroscopic probe for Zn2+ ion monitoring

We report the synthesis and application of a novel probe of the di-2-picolylamine (DPA)-conjugated triarylmethine (TAM) dye which has aimed at detecting Zn2+ ions. The 1:2 binding stoichiometry is estimated between Zn2+ and DPA-TAM a

Azobenzene chemosensor based on nitrogen chelator for the detection of Cu (II) ion in aqueous medium

A bis-pyridine unit containing azobenzene chemosensor for Cu2 + ion is designed and synthesized with good yield. The structure of the receptor I is determined by FT-IR, 1H NMR, 13C NMR, ESI-MS and single crystal XRD. The receptor I is constructed on the basis of internal charge transfer (ICT) mechanism with bis-pyridine unit acting as the binding part for Cu2 + ion. In solution, the proposed receptor I produces a cation induced 120 nm blue shift for Cu2 + ion from 457 nm to 337 nm with remarkable colour change from red to colourless. Whereas no significant colour change is observed upon addition of other metal ions in aqueous HEPES buffer (pH 7.0). Moreover, spectroscopic studies confirm the formation of 1: 1 stoichiometry between the receptor I and Cu2 + ion with an association constant of ca. 1.45 × 106 M- 1. The receptor I is highly specific to Cu2 + ions in aqueous solution attributed to the rational design of the molecular structure.

A selective fluorescent sensor for imaging Cd2+ in living cells

A selective sensor 1 for the fluorescent imaging of Cd2+ in living cells has been designed and synthesized based on an internal charge transfer (ICT) mechanism. It can distinguish Cd2+ from Zn2+ and can be used in both general fluorescence intensity microscopy and ratiometric fluorescence microscopy. Copyright

Exclusive detection of sub-nanomolar levels of palladium(II) in water: An excellent probe for multiple applications

A new colorimetric probe has been developed for the detection and estimation of PdII at sub-nanomolar concentrations. The probe consisted of rhodamine (signaling unit), which was linked with a bis-picolyl moiety (binding site) through a phenyl

New Sensitive and Selective Chemical Sensors for Ni2+and Cu2+Ions: Insights into the Sensing Mechanism through DFT Methods

We report the synthesis and theoretical study of two new colorimetric chemosensors with special selectivity and sensitivity to Ni2+ and Cu2+ ions over other metal cations in the CH3CN/H2O solution. Compounds (E)-4-((2-nitrophenyl)diazenyl)-N,N-bis(pyridin-2-ylmethyl)aniline (A) and (E)-4-((3-nitrophenyl)diazenyl)-N,N-bis(pyridin-2-ylmethyl)aniline (B) exhibited a drastic color change from yellow to colorless, which allows the detection of the mentioned metal cations through different techniques. The interaction of sensors with these metal ions induced a new absorption band with a hypsochromic shift to the characteristic signal of the free sensors. A theoretical study via time-dependent density functional theory (TD-DFT) was performed. This method has enabled us to reproduce the hypsochromic shift in the maximum UV-vis absorption band and explain the selective sensing of the ions. For all of the systems studied, the absorption band is characterized by a π→ π? transition centered in the ligand. Instead of Ni2+ and Cu2+ ions, the transition is set toward the σ? molecular orbital with a strong contribution of the 3dx2-y2 transition (π→ 3dx2-y2). These absorptions imply a ligand-to-metal charge transfer (LMCT) mechanism that results in the hypsochromic shift in the absorption band of these systems.

A New Compound for Sequential Sensing of Picric Acid and Aliphatic Amines: Physicochemical Details and Construction of Molecular Logic Gates

Picric acid (PA) at low concentration is a serious water pollutant. Alongside, aliphatic amines (AAs) add to the queue to pollute surface water. Plenty of reports are available to sense PA with an ultralow limit of detection (LOD). However, only a handful of works are testified to detect AAs. A new fluorescent donor-acceptor compound has been synthesized with inherent intramolecular charge transfer (ICT) character that enables selective and sensitive colorimetric quantitative detection of PA and AAs with low LODs in non-aqueous as well as aqueous solutions. The synthesized compound is based on a hemicyanine skeleton containing two pyridenylmethylamino groups at the donor and a benzothiazole moiety at the acceptor ends. The detailed mechanisms and reaction dynamics are explained spectroscopically along with computational support. The fluorescence property of the detecting compound changes due to protonation of its pyridinyl centers by PA leading to quenching of fluorescence and subsequently de-protonation by AAs to revive the signal. We have further designed logic circuits from the acquired optical responses by sequential interactions.

Colorimetric indicators for specific recognition of Cu2+ and Hg2+ in physiological media: Effect of variations of signaling unit on optical response

Easy to synthesize probes are designed using bispicolyl moiety as the receptor unit with two different signaling moieties, anthraquinone and bisindolyl. Both the compounds show ‘naked-eye’ sensing of Cu2+ and Hg2+ in ～100% aqueous me

Effects of the Ligand Structure of Cu(II) Complexes on Oxidative DNA Cleavage

Cu complexes were synthesized by substituting the hydrogen of the amine group of basic ligand 2,2′-dipicoylamine (dpca) (complex 2) with CH3CO (complex 1), phenyl (complex 3), and methyl (complex 4), respectively, and their DNA cleavage activity was investigated using linear dichroism (LD) and electrophoresis. The DNA cleavage efficiencies of Cu complexes 3 and 4 with phenyl and methyl, which are electron-donating functional groups, turned out to be the highest, and LD magnitudes rapidly decreased at 260 nm. In particular, Cu complex 3 showed a rapid LD magnitude reduction to 63% of the total for 90 min, and to 50% of the total at 12 min. DNA cleavage efficiencies were high in the order of phenyl > methyl > HCH3CO, and the highest DNA cleavage efficiency was observed in the presence of electron-donating groups. The electrophoresis results are also consistent with the changes in LD spectra over time. The Cu complexes (1–4) were found to cleave DNA through oxidative pathways, and the major reaction oxygen species involved in DNA cleavage were the superoxide radical (·O2?), singlet oxygen (1O2), and hydroxyl radical (·OH).

A highly sensitive chemosensor for rapid recognition of Cu2+ and HSO3? in 100% aqueous solution

Dual-responsive chemosensors have garnered much research interests owing to the ability of recognizing two analytes simultaneously. Herein, the chemosensor BPIS composed of hemicyanine and 2, 2′-dipyridylamine (DPA) was facilely synthesized for sensitive and expeditious recognition of Cu2+ and HSO3? in 100% aqueous solution. By adding Cu2+, BPIS showed substantial spectral changes accompanied by a noticeable color change from pink to yellow under daylight. The absorbance and fluorescence intensity were linearly correlated to the Cu2+ concentration, enabling the quantitative recognition of Cu2+. The limit of detection (LOD) for Cu2+ was down to 4.02 × 10?9 M. The response time of BPIS towards Cu2+ was 10 s, imparting BPIS great potential in real-time detection of Cu2+. Meanwhile, BPIS manifested ratiometric fluorescence response by introducing HSO3? owing to the 1,4-addition between HSO3? and the unsaturated C[dbnd]C bond of BPIS. The color of the BPIS solution progressively faded from pink to colorless with increasing HSO3? concentration, and a LOD of 3.47 × 10?9 M was obtained. In addition, BPIS-coated test paper was found to be an efficient tool for fast, sensitive, portable detection of Cu2+ and HSO3? by naked eyes. More importantly, the precise detection of Cu2+ and HSO3? in real water and sugars were realized, respectively, by capitalizing on BPIS as the signal tool.

Protic media enhanced protodeboronation for a potential H2O2-sensitive ligand system

The detection of elevated concentrations of reactive oxygen species (ROS) such as H2O2 represents a promising route to identify oxidative misregulation in cells, a hallmark of carcinoma and neurodegeneration. Magnetic resonance imaging (MRI) presents an opportunity to detect ROS over a greater portion of the body compared to strategies such as fluorescence. To sense hydrogen peroxide, potential Fe2+ and Co2+ MRI sensors were synthesized by appending pinacolborane to two amino-pyridine ligand scaffolds. These were designed to expose phenol upon reaction with H2O2, turning on PARACEST (Paramagnetic Chemical Exchange Saturation Transfer) and allowing detection by MRI. Instead of yielding a phenol upon exposure to oxidative conditions, protodeboronation was observed as the major product even under mild conditions. Optimization of oxidation conditions allowed access to the phenolic analogue of the two ligands studied in 11% and 17% conversion under organic conditions. Treatment of the Fe2+ and Co2+ complexes with H2O2 resulted in rapid, partial demetallation with no evidence of the bound or free ligand undergoing an oxidative transformation. These results stress the importance of establishing stability of potential MRI contrast agents in aqueous conditions.