14031-99-3

Upstream product

• 1779-49-3 Methyltriphenylphosphonium bromide 
• 120-21-8 4-Diethylaminobenzaldehyde 
• 99-92-3 p-aminobenzophenone 
• 64-19-7 acetic acid 
• 1520-21-4 4-vinyl benzylamine 

Downstream Products

• 148080-35-7 5-{(E)-2-[4-(diethylamino)phenyl]ethenyl}thiophene-2-carboxaldehyde 

Relevant academic research and scientific papers

Solvent-dependent photophysics of a red-shifted, biocompatible coumarin photocage

Controlling the activity of biomolecules with light-triggered photocages is an important research tool in the life sciences. We describe here a coumarin photocage that unusually combines the biocompatible optical properties of strong absorption at a long wavelength close to 500 nm and high photolysis quantum yields. The favourable properties are achieved by synthetically installing on the photocage scaffold a diethyl amino styryl moiety and a thionoester group rather than the lactone typical for coumarins. The photocage's photophysics are analysed with microsecond transient absorption spectroscopy to reveal the nature of the excited state in the photolysis pathway. The excited state is found to be strongly dependent on solvent polarity with a triplet state formed in DMSO and a charge-separated state in water that is likely due to aggregation. A long triplet lifetime is also correlated with a high photolysis quantum yield. Our study on the biocompatible photocage reveals fundamental insight for designing advanced photocages such as longer wavelengths in different solvent conditions tailored for applications in basic and applied research.

Thiophene-based dyes for probing membranes

We report the synthesis of four new cationic dipolar push-pull dyes, together with an evaluation of their photophysical and photobiological characteristics pertinent to imaging membranes by fluorescence and second harmonic generation (SHG). All four dyes consist of an N,N-diethylaniline electron-donor conjugated to a pyridinium electron-acceptor via a thiophene bridge, with either vinylene (-CHCH-) or ethynylene (-CC-) linking groups, and with either singly-charged or doubly-charged pyridinium terminals. The absorption and fluorescence behavior of these dyes were compared to a commercially available fluorescent membrane stain, the styryl dye FM4-64. The hyperpolarizabilities of all dyes were compared using hyper-Rayleigh scattering at 800 nm. Cellular uptake, localization, toxicity and phototoxicity were evaluated using tissue cell cultures (HeLa, SK-OV-3 and MDA-231). Replacing the central alkene bridge of FM4-64 with a thiophene does not substantially change the absorption, fluorescence or hyperpolarizability, whereas changing the vinylene-links to ethynylenes shifts the absorption and fluorescence to shorter wavelengths, and reduces the hyperpolarizability by about a factor of two. SHG and fluorescence imaging experiments in live cells showed that the doubly-charged thiophene dyes localize in plasma membranes, and exhibit lower internalization rates compared to FM4-64, resulting in less signal from the cell cytosol. At a typical imaging concentration of 1 μM, the doubly-charged dyes showed no significant light or dark toxicity, whereas the singly-charged dyes are phototoxic even at 0.5 μM. The doubly-charged dyes showed phototoxicity at concentrations greater than 10 μM, although they do not generate singlet oxygen, indicating that the phototoxicity is type I rather than type II. The doubly-charged thiophene dyes are more effective than FM4-64 as SHG dyes for live cells.

A study on regulating the conjugate position of NLO chromophores for reducing the dipole moment and enhancing the electro-optic activities of organic materials

In order to improve the first-order hyperpolarizability (β) of the chromophore and transform it into a high macroscopic electro-optic activity, a series of novel second-order nonlinear optical chromophores with different push-pull electron groups introduced on the thiophene π-conjugate bridge for tuning the shape and dipole moment (μ) of chromophores were designed and synthesized. These chromophores are based on the same thiophene π-conjugated bridge, where the donor (N,N-diethylaniline) and acceptor (2-(3-cyano-4,5,5-trimethylfuran-2(5H)-ylidene)malononitrile or malononitrile) are linked to positions 2 and 3 of thiophene, respectively, affording a boomerang-like shape instead of a rod-like shape. Besides, an electron-poor group, Br (bromine atom), or an electron-rich group, DEA (N,N-diethylaniline), as an auxiliary acceptor or donor are linked to position 5 of thiophene. In addition, all chromophores showed good thermal stability as per the results from the DSC and TGA analysis. Through UV-vis analysis and DFT calculation, it has been concluded that chromophores with additional electron-rich groups as auxiliary donors display better intermolecular charge-transfer (ICT) absorption and lower HOMO-LUMO energy gaps (ΔE). Furthermore, the boomerang-like chromophore with the same push-pull structure shows a smaller dipole moment (μ) and β value than the traditional FTC. The poling results of guest-host EO polymers FTC/APC, FTC-H/APC, FTC-Br/APC and FTC-DEA/APC with the same number density afford r33 values of 17 pm V-1, 11 pm V-1, 10 pm V-1 and 25 pm V-1, respectively. Although the β value of FTC-DEA is smaller than that of FTC, the r33 value of FTC-DEA (25 pm V-1) is 47% greater than that of FTC (17 pm V-1) under the same number density. Hence, the above-mentioned results indicated that regulating the conjugate position of chromophores can efficiently decrease the dipole moment of the chromophores, weakening the dipole-dipole interactions and thereby enhancing the macroscopic electro-optical activity of poled polymers. These results indicate the potential application of these novel chromophores in electro-optical devices.

COMPOUNDS AS MODULATORS OF TLR2 SIGNALING

The present disclosure relates to compounds, pharmaceutical compositions comprising such compounds, and use of such compounds in methods of treatment or in medicaments for treatment of inflammatory diseases and certain neurological disorders that are related to inflammatory signaling processes, including but not limited to misfolded proteins.

Direct catalytic N-alkylation of amines with carboxylic acids

A straightforward process for the N-alkylation of amines has been developed applying readily available carboxylic acids and silanes as the hydride source. Complementary to known reductive aminations, effective C-N bond construction proceeds under mild conditions and allows obtaining a broad range of alkylated secondary and tertiary amines, including fluoroalkyl-substituted anilines as well as the bioactive compound Cinacalcet HCl.