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A new chemodosimeter SWJT-31 with an aggregation-induced emission (AIE) effect was designed and constructed. Upon increasing the water fraction in the solution, it exhibited typical AIE, which showed bright red fluorescence at 610 nm. SWJT-31 could sensitively and specifically recognize hydrazine by the TICT effect with an LOD of 33.8 nM, which was much lower than the standard of the USEPA. A portable test strip prepared using SWJT-31 was also developed for the visual detection of hydrazine. Eventually, it was successfully used for the detection of hydrazine in water samples and HeLa cells.

A new fluorescent probe SWJT-23 with lysosomal targeting ability for detection of hypobromous acid (HBrO) was synthesised based on the naphthalimide skeleton. This probe exhibited a fast response (within 3s), a low detection limit (1.24 nM), excellent selectivity and a high fluorescence quantum yield ( Φ = 0.490). Moreover, SWJT-23 not only realized the sensitive detection of HBrO in cells and water samples, but also was fabricated as a paper-based sensor. In consequence, SWJT-23 is expected to be an efficient and powerful tool for monitoring HBrO in organisms and the environment in realistic scenarios.

Based on the correlation between inflammation and reactive oxygen species and viscosity, a fluorescent probe (SWJT-19) was designed for a relay detection of hypochlorite ions and viscosity. The synthesized probe could quickly and selectively detect hypochlorite ions, as well as viscosity of the system effectively. Moreover, the probe had been successfully applied to sequentially detect hypochlorite ions and viscosity in organisms, as well as imaging in mouse inflammation.

Inspired by the synthetic method of benzoxazine derivatives and our previous research, a fluorescent probe (SWJT-6) was designed for formaldehyde (FA) detection based on the cyclization reaction. The synthetic SWJT-6 showed excellent colorimetric and ratiometric response to formaldehyde, and could be perfectly used as test strips to detect formaldehyde. It also showed a fast detection time (3 min), low detection limit (5.65 μM) and high selectivity for formaldehyde within various interfering analytes. In addition, SWJT-6 has been successfully applied in bioimaging of intracellular and lysosomal formaldehyde in both HeLa cells and zebrafish.

A new ratiometric and colorimetric probe (SWJT-16) based on the isophorone skeleton to detect diethyl chlorophosphite (DCP), a nerve agent mimic, was designed and synthesized. SWJT-16 underwent a nucleophilic substitution reaction with DCP in DMF, leading to a large emission shift (Δ λ em = 174 nm) accompanied by a significant color change from blue to yellow under visible light. All these changes occurred within 6 seconds, faster than those of most reported ratiometric fluorescent probes for DCP. Furthermore, SWJT-16 was successfully employed to monitor gaseous DCP.

A simple fluorescein derivative as a fluorescent probe was synthesized for the detection of malondialdehyde (MDA) through a synergistic reaction to achieve ring-opening of fluorescein and formation of a benzohydrazide derivative. It exhibited high sensitivity and selectivity for MDA detection. The probe could also detect MDA quickly (within 60 s) and visually via UV-vis and fluorescent modes. Moreover, this probe showed good performance in the imaging of MDA in living cells and bacteria.

A novel ratiometric probe (SWJT-10) based on isophorone derivatives has been designed and synthesized for the detection of formaldehyde (FA). This probe displayed an obvious ratiometric fluorescence response to FA with a blue shift from the NIR (680 nm) to the yellow light region (600 nm) in aqueous solution. And it showed good selectivity, high sensitivity and a fast response to FA (less than 5 s) due to a new recognition mechanism. Moreover, SWJT-10 has been applied to monitor FA in living cells and zebrafish.

Based on aggregation-induced emission (AIE) and twisted intramolecular charge transfer (TICT) mechanisms, a fluorescent probe SWJT-12 for the detection of ClO - was designed by using the CN bond as a reactive group. This synthesized probe can react with ClO - in a high aqueous phase, and it shows a large Stokes shift (144 nm) and low biological toxicity. Its limit of detection was calculated to be 0.28 μM. Furthermore, SWJT-12 was successfully used for ratiometric imaging of the exogenous hypochlorite anion in living cells.

A novel near-infrared fluorescent probe (SWJT-2) has been designed and synthesized for the detection of methylglyoxal (MGO). It showed a low detection limit (0.32 μM), high selectivity and the fastest detection (15 min) over various reactive carbonyl compounds in aqueous solution. SWJT-2 had been successfully applied to bioimaging in HeLa cells to detect exogenous and endogenous MGO.

The synthetic progress of bioactive 2,7'-cyclolignans is reviewed. After a short introduction to biosynthesis and chemoenzymatic synthesis, the chemical synthesis of various aryltetralin, dihydronaphthalene and 7'-arylnaphthalene-types of these lignans is demonstrated. Notably, newly developed methods, such as Pd-catalyzed C-H arylation, organocatalysis and photocatalysis under visible-light, are discussed during the construction of their skeleton. These efforts will stimulate further development of novel synthetic strategies for this kind of natural product with important biological activities.

The first total synthesis of (+)-adunctin C ( ent -1) and (+)-adunctin D (2), two monoterpene-substitued dihydrochalcones isolated from Piper aduncum (Piperaceae), was achieved. A regioselective oxidative [3 + 2] cycloaddition of acylphloroglucinol with (-)-β-phellandrene was developed to construct their unique spirobenzofuran skeleton. The absolute configurations of natural adunctins 1 and 2 were thus assigned through these endeavors.

A dicyanoisophorone/acrylate-combined probe (DDP) was synthesized and designed as a near-infrared (NIR) fluorescent sensor for the rapid identification of Cys over Hcy and GSH in aqueous solution with a large Stokes shift (143 nm). The detection limit of Cys was 1.23 μM, which was lower than that of the intracellular Cys concentration. DDP was cell membrane-permeable and had been successfully applied to the detection of intracellular Cys in HeLa cells. The detection mechanism was determined by 1 H NMR titration, MS and DFT calculations.

A base-promoted addition of DMA (N,N-dimethylacetamide) to 1,1-diarylethylenes has been developed, and it provides a new strategy for the synthesis of N,N-dimethyl-4,4-diarylbutanamides from 1,1-diarylethylenes at room temperature. This method allows us to achieve the goal of synthesizing (-)-sacidumlignan B, and provides simple operation and broad substrate scope by avoiding the use of transition metal catalysts.

A copper-catalyzed cascade reaction using isatins and amidine hydrochlorides for the synthesis of 2-(1,3,5-triazin-2-yl)aniline derivatives has been developed. This reaction features commercially available starting materials, mild reaction conditions and good functional group tolerance.

Relay recognition of copper(ii) ions and biothiols via a fluorescence "on-off-on" cascade was designed and realized as a new sequential combination of cations and small molecules. Probe 1 bearing a fluorescein skeleton was thus synthesized, which performed well in 100% HEPES buffer (pH = 7.0) solution, as a highly sensitive, selective fluorescence sensor for Cu 2+ . The limit of detection (LOD, 0.017 ppm) was obtained, and this value is much lower than 1.3 ppm, allowed by US EPA. The 1 : 1 complex generated from fast sensing of Cu 2+ when excited at 491 nm, showed good relay recognition for biothiols (i.e., Cys, Hcy and GSH with low detection limits of 0.12 μM, 0.036 μM and 0.024 μM, respectively) via remarkable fluorescence enhancement. The origin of this relay process was disclosed through ESI-MS and corresponding density functional theory (DFT) computations. Notably, probe 1 can be utilized for the construction of a molecular logic gate with the IMPLICATION function by using the above fluorescence changes. Moreover, this relay recognition was also applied to HepG2 cell imaging successfully.

Collective synthesis of anti-malarial 2,7'-cyclolignans has been stereoselectively achieved employing (±)-cyclogalgravin (2) as a linchpin through a series of functional group conversions, including redox reactions. Interestingly, 2 can be correlated with the neolignan (±)-kadangustin J (1) isolated from a different plant source, through a highly efficient dehydrative cyclization reaction with excellent diastereotopic differentiation of the veratryl group and concomitant construction of the C1–C7 bond. It is noteworthy that the first total synthesis of stereodivergent (±)-8,8'-epi-aristoligone (5), (±)-8'-epi-aristoligone (7), (±)-8'-epi-8-OH-aristoligone (8) and (±)-8'-epi-aristoligol (9) was demonstrated.

New Tb(iii) and Eu(iii) complexes have been synthesized as potential pH probes using a tripodal substituted-salicylic ligand (H3). Among them, this carboxylate ligand is found to be a good sensitizer for Tb(iii) emission owing to the superior match of the triplet energy level of the ligand with the (5)D4 emitting level of Tb(iii). The resulting · complex exhibited high sensitivity in the physiological pH range with significant "off-on-off" fluorescence changes in aqueous solution. Furthermore, this unique rare-earth complex has been successfully used to monitor pH variations within HeLa cells and with filter papers.

Efficient synthesis of (±)-sacidumlignan D (4) has been successfully achieved employing Ueno-Stork radical cyclization of α-bromo acetal 21 as a key step. Two synthetic approaches for the symmetrical diaryl ketone 19 have been discussed in detail. Notably, sacidumlignan A (1) can be also efficiently synthesized in only 7 steps with 25% overall yield, where acid triggered tandem reaction starting from analogous Ueno-Stork cyclization product 27 played an important role. Moreover, potentially biomimetic conversion from (±)-sacidumlignan D (4) to sacidumlignan A (1) could be realized.