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In this study, a series of organo difluoroboron probes with a BF2 benzamide moiety was designed, prepared and evaluated. Among them, 2c displayed the best optical and biological properties, and may be used as a useful near-infrared fluorescent probe for the detection of Aβ plaques and neurofibrillary tangles in AD.

The prostate-specific membrane antigen (PSMA) is considered to be an excellent theranostic target of prostate cancer (PCa). In this study, three 18F-labeled PSMA tracers with a more lipophilic quinoline functional spacer were designed, synthesized, and evaluated based on the Glu-Ureido-Lys binding motif. The effect of structure-related lipophilic difference on distribution and excretion of these tracers in vitro and in vivo (cells, rodent, primate, and human) was investigated by comparing with [18F]DCFPyL. There is no significant correlation between the renal elimination and the lipophilicity of the tracers in all species. However, the higher the lipophilicity of tracer, the higher the radioactivity accumulation in the liver of primate and human, and the less radioactivity is to excrete to the bladder with urine. The screened tracer [18F]8c, with a Ki value of 4.58 nM, displayed notable low bladder retention and demonstrated good imaging properties in patients with PCa.

Objective In order to find lead compound with anti-HBV activity from peroxo-bridged diosgenin derivatives obtained with Eosin Y as the photosensitizer. Method Eosin Y was used as the photosensitizer to activate the oxygen in the air to synthesize novel diosgenin derivatives with peroxo-bridge. The structures of synthesized compounds were identified by NMR and HR-MS. Their cytotoxicity and antihepatitis B activity were evaluated via MTS assay and ELISA method, respectively. Results Six diosgenin derivatives were synthesized, three of which contained peroxo-bridge, and their structures were confirmed by spectroscopy. It showed that 5α,8α-peroxo-6-alkenyl-diosgenin (7) could suppress the production of HBsAg on transfected HepG2.2.15 cells at low-toxic concentration and the inhibition rate on HepG2.2.15 cells was 18.28% at 12.50 µg/mL, better than that of 3TC (7.30% at 12.50 µg/mL) and others. Conclusion Due to its lower cytotoxicity and potential anti-hepatitis B activity, compound 7 could be developed as the promising candidate of anti-hepatitis B drug. It also indicated that the peroxo-bridged derivatives had potential biological values for developing clinical agents.

A comparative study of plasmonic-enhanced single-molecule fluorescence (PESMF) induced by four gold nanoantennas is reported. The gold triangular nanoplate (Au TNP) is the optimal PESMF substrate for Cy5.5 owing to its sharpest point and strongest electric fields. The Au TNP is chosen for the preparation of a telomerase sensor.

Previous studies have demonstrated that natural steroid compounds containing a peroxide bridge exhibited potential anti-hepatitis B virus activity. To continue our research, a simple and regioselective methodology, using Eosin Y as a clean photosensitized oxidation catalyst, was developed for the synthesis of a peroxide bridge in steroids. The method that using Eosin Y as the catalyst was exposed to visible light and furbished in high yields, did not involve tedious work-up or purification, and avoided using environmentally hazardous solvents. It can be regarded as a green protocol. Moreover, a series of cholesterol and β-sitosterol derivatives containing a peroxide bridge were synthesized using this method and screened for their anti-HBV activity. Among the compounds synthesized in this research, 5α,8α-cyclicobioxygen-6-vinyl-3-oxo-cholesterone (1f, 3.13 μg ml−1) had the most potent activity with inhibition rates of 77.45% ± 6.01% and 58.73% ± 8.64% on the secretion of HBsAg and HBeAg antigens, respectively, after 8 days. Further acute toxicity test showed that the LD50 value of compound 1f was 362.46 mg kg−1 after an intraperitoneal injection in mice. Moreover, structure–activity relationships of cholesterol and β-sitosterol derivatives were briefly discussed.