A novel strategy for the dehydrogenation of the NH-NH bond is disclosed using potassium tert-butoxide (tBuOK) in liquid ammonia (NH ) under air at room temperature. Its synthetic value is well demonstrated by the highly efficient synthesis of aromatic azo compounds (up to 100 % yield, 3 min), heterocyclic azo compounds, and dehydrazination of phenylhydrazine. The broad application of this strategy and its benefit to chemical biology is proved by a novel, convenient, one-pot synthesis of aliphatic diazirines, which are important photoreactive agents for photoaffinity labeling.

Alternative one-pot synthesis of 3-(trifluoromethyl)-3-phenyldiazirine derivatives from corresponding tosyloximes is developed. The deprotonation of intermediate diaziridine by NH2(-) is a new approach for construction of diazirine. Moreover, a novel synthesis of optically pure (trifluoromethyl)diazirinylphenylalanine derivatives was attempted involving these methods.

The development of DNA‐targeted photodynamic therapy (PDT) agents for cancer treatment has drawn substantial attention. Herein, the design and synthesis of dinuclear IrIII‐containing luminescent metallohelices with tunable PDT efficacy that target mitochondrial DNA in cancer cells are reported. The metallohelices are fabricated using dynamic imine‐coupling chemistry between aldehyde end‐capped fac‐Ir(ppy)3 handles and linear alkanediamine spacers, followed by reduction of the imine linkages. The length and odd–even character of the diamine alkyl linker determined the stereochemistry (helicates vs. mesocates). Compared to the helicates, the mesocates exhibit improved apoptosis‐induction upon white‐light irradiation. Molecular docking studies indicate that the mesocate with a proper length of diamine spacers shows stronger affinity for the minor groove of DNA. This study highlights the potential of DNA‐targeting IrIII‐containing metallohelices as PDT agents.

Saccharin is one of the most common artificial sweeteners that has a bitter taste at high concentrations. Currently, there are no detailed functional analyses of these gustatory receptors. Therefore, we designed and synthesized photoreactive saccharin derivatives that contain a (trifluoromethyl) diazirinyl moiety at the 5- or 6-position for use as functional analysis tools for photoaffinity labeling

A series of organic dyes with alkaline pyridine-N-oxide as the electron acceptor and anchoring group have been synthesized and applied in dye-sensitized solar cells. Photoelectrical data show a good coordination between pyridine-N-oxide and TiO 2 films, which effectively guarantee the injection and adsorption of the dye molecules. With the simple WL102 dye, the best photon-toelectron conversion efficiency of 3.72% and an excellent IPCE value about 95% have been achieved under optimized conditions.

Novel hydrogen/deuterium exchange for aromatic α-amino acids and their corresponding peptides were performed through the use of deuterated trifluoromethanesulfonic acid (TfOD). Detailed analysis of the exchange revealed that equal hydrogen/deuterium exchange was observed for phenylalanine, and specific exchange at the ortho-positions of phenol for tyrosine was also detected. The stereochemistry of the aromatic α-amino acids was retained under the exchange conditions. The hydrogen/deuterium exchange properties for these aromatic α-amino acids are identical for peptides that contain several aromatic α-amino acids. The exchange proceeded significantly faster than previous methods. Detailed analysis of the exchange revealed that the method could be controlled by temperature, time, and the amount of reagent

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Aliphatic diazirines have been widely used as prominent photophores for photoaffinity labeling owing to their relatively small size which can reduce the steric effect on the natural interaction between ligands and proteins. Based on our continuous efforts to develop efficient methods for the synthesis of aliphatic diazirines, we present here a comprehensive study about base-mediated one-pot synthesis of aliphatic diazirines. It was found that potassium hydroxide (KOH) can also promote the construction of aliphatic diazirine with good efficiency. Importantly, KOH is cheaper, highly available, and easily handled and stored compared with the previously used base, potassium tert-butoxide (t-BuOK). Gram-scale study showed that it owned great advantages in being used for the large-scale production of aliphatic diazirines. This protocol is highly neat and the desired products can be easily isolated and purified. As the first comprehensive study of the base-mediated one-pot synthesis of aliphatic diazirines, this work provided good insight into the preparation and utilization of diazirine-based photoaffinity labeling probes.