In recent decades, HOCl research has attracted a lot of scientists from around the world. This chemical species is well known as an important player in the biological systems of eukaryotic organisms including humans. In the human body, HOCl is produced by the myeloperoxidase enzyme from superoxide in very low concentrations (20 to 400 μm); this species is secreted by neutrophils and monocytes to help fight pathogens. However, in the condition called “oxidative stress”, HOCl has the capability to attack many important biomolecules such as amino acids, proteins, nucleotides, nucleic acids, carbohydrates, and lipids; these reactions could ultimately contribute to a number of diseases such as neurodegenerative diseases (AD, PD, and ALS), cardiovascular diseases, and diabetes. In this review, we discuss recent efforts by scientists to synthesize various fluorophores which are attached to receptors to detect HOCl such as: chalcogen‐based oxidation, oxidation of 4‐methoxyphenol, oxime/imine, lactone ring opening, and hydrazine. These synthetic molecules, involving rational synthetic pathways, allow us to chemoselectively target HOCl and to study the level of HOCl selectivity through emission responses. Virtually all the reports here deal with well‐defined and small synthetic molecular systems. A large number of published compounds have been reported over the past years; this growing field has given scientists new insights regarding the design of the chemosensors. Reversibility, for example is considered important from the stand point of chemosensor reuse within the biological system; facile regenerability using secondary analytes to obtain the initial probe is a very promising avenue. Another aspect which is also important is the energy of the emission wavelength of the sensor; near‐infrared (NIR) emission is favorable to prevent autofluorescence and harmful irradiation of tissue; thus, extended applicability of such sensors can be made to the mouse model or animal model to help image internal organs. In this review, we describe several well‐known types of receptors that are covalently attached to the fluorophore to detect HOCl. We also discuss the common fluorophores which are used by chemist to detect HOCl, Apart from the chemical aspects, we also discuss the capabilities of the compounds to detect HOCl in living cells as measured through confocal imaging. The growing insight from HOCl probing suggests that there is still much room for improvement regarding the available molecular designs, knowledge of interplay between analytes, biological applicability, biological targeting, and chemical switching, which can also serve to further sensor and theurapeutic agent development alike.

A short, protecting-group-free synthesis is achieved. The synthesis is step-efficient and general. A Diels-Alder and Stille cross-coupling approach includes key transformations, allowing for a competitive synthesis which involves a rare halophenol Stille cross-coupling study. The phenylselenyl and phenylsulfenyl analogues were prepared as novel compounds in good overall yield. The applicability of one of the intermediates as a potential probe for reactive oxygen species (ROS) in water is investigated.

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A concise strategy has been developed for the synthesis of the bicyclic macrolide-butenolide core structures of various natural products with the macrolide ring size ranging from 12-to 16-membered.The bicyclic structure was easily assembled using the relay ring-opening/double ring-closing metathesis strategy. An efficient synthesis of (AE)-desmethyl manshurolide has been achieved as an application of this strategy.

As imple one-step synthesis of fluorescent probe HemiSe has been developed for the detection of superoxide (O 2 C À ). The probe undergoes reaction specificallyw ith O 2 C À when in the presence of other competitive ROS/RNS/metal ions. The diphenylselenide was incorporated to completely quench the fluorescenceo ft he hemicyanine unit through the action of ap hotoinduced electron transfer (PET) photomechanism.H owever,a fter the addition of O 2 C À ,t he latent fluorophore regains its fluorescence owing to the reaction at the C=Cb ond of the hemicyanine with O 2 C À through nucleophilic attack;t he increase in blue emission is due to ar eac-tion of the doubleb ond within HemiSe followed by an increase in fluorescenceq uantum yield (F)u pt o0 .45;t he limit of detection (LOD) is 11.9 nm.Atime-dependent study shows that HemiSe can detect superoxide within 13 min with high sensitivity,h igh selectivity,o ver aw ide pH range, and through confirmation with ax anthine/xanthine oxidase biochemical assay (l em = 439 nm). As tudy in the RAW2 64.7 macrophage living cells also shows that HemiSe is not toxic, cell permeable (experimental log P = 2.11);c onfocali maging resultss how that HemiSe can detect O 2 C À in endogenous and exogeneous systems.[a] Dr.