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The formation of amyloid-β (Aβ) plaques in the brain is one of the main pathological features of Alzheimer's disease (AD). The imaging probes, capable of detecting Aβ deposition, are important tools for early diagnosis of AD. In this article, we designed, synthesized and evaluated a cyanine-based near-infrared fluorescence (NIRF) probe ZT-1 for the detection of Aβ deposits in the brain. The probe had excellent fluorescent properties with an emission maximum above 720 nm upon binding to Aβ aggregates with affinity of 445.0 nM (K d ). Furthermore, ZT-1 exhibited good biostability, photostability, and binding selectivity toward Aβ 1-42 aggregates by in vitro fluorescence staining experiments. In vivo NIRF imaging result also revealed that our probe could efficiently differentiate transgenic and wild-type mice. All these studies indicated that ZT-1 is a promising fluorescent probe for Aβ plaques in the AD brains., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

A series of resveratrol dimer derivatives against Alzheimer's disease (AD) was obtained by structural modification and transformation using resveratrol as substrate. Biological analysis revealed that these derivatives had moderate inhibitory activity against human monoamine oxidase B (hMAO-B). In particular, 3 and 7 showed the better inhibitory activity for hMAO-B (IC 50  = 3.91 ± 0.23 μM, 0.90 ± 0.01 μM) respectively. Compound 3 (IC 50  = 46.95 ± 0.21 μM for DPPH, 1.43 and 1.74 trolox equivalent by ABTS and FRAP method respectively), and 7 (IC 50  = 35.33 ± 0.15 μM for DPPH, 1.70 and 1.97 trolox equivalent by ABTS method and FRAP method respectively) have excellent antioxidant effects. Cellular assay shown that 3 and 7 had lower toxicity and were resistant to neurotoxicity induced by oxidative toxins (H 2 O 2 , rotenone and oligomycin-A). More importantly, the selected compounds have neuroprotective effects against ROS generation, H 2 O 2 -induced apoptosis and a significant in vitro anti-inflammatory activity. The results of the parallel artificial membrane permeability assay for blood-brain barrier indicated that 3 and 7 would be predominant to cross the blood-brain barrier. In this study, mouse microglia BV2 cells were used to establish cell oxidative stress injury model with H 2 O 2 and to explore the protective effect and mechanism of 3 and 7. In general, 3 and 7 can be considered candidates for potential treatment of AD., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

A series of salicyladimine derivatives were designed, synthesized and evaluated as multi-target-directed ligands for the treatment of Alzheimer's disease (AD). Biological activity results demonstrated that some derivatives possessed significant inhibitory activities against amyloid-β (Aβ) aggregation and human monoamine oxidase B (hMAO-B) as well as remarkable antioxidant effects and low cell toxicity. The optimal compound, 5, exhibited excellent potency for inhibition of self-induced Aβ 1-42 aggregation (91.3±2.1%, 25μM), inhibition of hMAO-B (IC 50 , 1.73±0.39μM), antioxidant effects (43.4±2.6μM of IC 50 by DPPH method, 0.67±0.06 trolox equivalent by ABTS method), metal chelation and BBB penetration. Furthermore, compound 5 had neuroprotective effects against ROS generation, H 2 O 2 -induced apoptosis, 6-OHDA-induced cell injury, and a significant in vitro anti-inflammatory activity. Collectively, these findings highlighted that compound 5 was a potential balanced multifunctional neuroprotective agent for the development of anti-AD drugs., (Copyright © 2017. Published by Elsevier Ltd.)