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Noninvasive treatments for terminal cancer patients constitute a new trend in tumor treatment. Therefore, phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), has attracted considerable interest. Light and a photosensitizer (PS) are employed in both treatment methods. For PDT, the PS generates reactive oxygen species (ROS) when exposed to light, whereas for PTT, the PS generates heat. In this regard, the systematic design of new PSs has become an active area of phototherapy research in an effort to solve the problems associated with conventional PSs. In the past decade, activatable and heavy‐atom‐free PSs have become significant research areas. Therefore, we discuss our recent contributions to the PDT and PTT in this account. [ABSTRACT FROM AUTHOR]

A coumarin-based two-photon (TP) fluorescent off–on probe has been developed for detecting tyrosinase activity. High selectivity, sensitivity and biocompatibility enable the probes to successfully image tyrosinase activity in live cells and tissues using TP microscopy. [ABSTRACT FROM AUTHOR]

Selective fluorescence imaging of biomarkers in vivo and in situ for evaluating orthotopic hepatocellular carcinoma (HCC) chemotherapy remains a great challenge due to current imaging agents suffering from the potential interferences of other hydrolases. Herein, we observed that carbamate unit showed a high selectivity toward the HCC‐related biomarker carboxylesterase (CE) for evaluation of treatment. A near‐infrared two‐photon fluorescent probe was developed to not only specially image CE activity in vivo and in situ but also target orthotopic liver tumor after systemic administration. The in vivo signals of the probe correlate well with tumor apoptosis, making it possible to evaluate the status of treatment. The probe enables the imaging of CE activity in situ with a high‐resolution three‐dimensional view for the first time. This study may promote advances in optical imaging approaches for precise imaging‐guided diagnosis of HCC in situ and its evaluation of treatment. [ABSTRACT FROM AUTHOR]

Novel thiocarbonyl derivatives (NIS and CRNS) with excellent ROS generation abilities are synthesized and studied as potential photosensitizers for one- and two-photon excited photodynamic therapy. In particular, NIS-Me and CRNS display outstanding phototoxicity toward HeLa cells under two-photon excitation (800 nm) with negligible dark toxicity. [ABSTRACT FROM AUTHOR]

A new water-soluble fluorescent probe 1 based on hemicyanine dye is designed for selective detection of glutathione (GSH). Probe 1 shows a tremendous colorimetric and ratiometric fluorescence response toward GSH with high selectivity over cysteine/homocysteine. After nucleophilic aromatic substitution reaction with GSH, probe 1 undergoes an intramolecular aldimine condensation that leads to forming a ring, which is accompanied by 107 and 41 nm red-shifts in the absorption and fluorescence spectra, respectively. Subsequent experiments in living cells indicate that probe 1 has a good photostability and response to mitochondrial GSH level in a ratiometric manner. [ABSTRACT FROM AUTHOR]

In this present study, two possible channels including channels A and B on the stereoselective synthesis of imidazoles by the reaction between 1-substituted-2-methylimidazoles ( R1 ), cyanophenylacetylenes ( R2 ), and acetaldehydes ( R3 ) have been studied using the density functional theory (DFT). There are both four processes involved in both the two channels: the nucleophilic attack of R1 on R2 for the formation of E - or Z -configurational zwitterionic intermediate, the proton transfer process, the addition of another reactant R3 , and the rearrangement to form the final product. The calculated results demonstrate that the first step is the rate-determining step, and is associated with the energy barrier of 25.32 in Channel A and 19.24 kcal/mol in Channel B respectively, which show Channel B is more energy favorable. This is in good agreement with the experimental result that the Z -isomer is the single product. Moreover, the distortion/interaction reactivity analysis was performed to explain why the transition state in Channel B is more stable. Furthermore, the calculations on the solvation effects using IEFPCM model have also been carried out. [ABSTRACT FROM AUTHOR]

Selective fluorescence imaging of biomarkers in vivo and in situ for evaluating orthotopic hepatocellular carcinoma (HCC) chemotherapy remains a great challenge due to current imaging agents suffering from the potential interferences of other hydrolases. Herein, we observed that carbamate unit showed a high selectivity toward the HCC-related biomarker carboxylesterase (CE) for evaluation of treatment. A near-infrared two-photon fluorescent probe was developed to not only specially image CE activity in vivo and in situ but also target orthotopic liver tumor after systemic administration. The in vivo signals of the probe correlate well with tumor apoptosis, making it possible to evaluate the status of treatment. The probe enables the imaging of CE activity in situ with a high-resolution three-dimensional view for the first time. This study may promote advances in optical imaging approaches for precise imaging-guided diagnosis of HCC in situ and its evaluation of treatment., (© 2021 Wiley-VCH GmbH.)