Design, synthesis and structure-activity relationship of dihydrobenzoquinolines as novel inhibitors against influenza A virus.

Novel dihydrobenzo[h]quinolines (DHBQs), the products of an efficient catalyst-free three-component reaction (3CR) recently developed by us, possess useful and strong aggregation-induced emission (AIE) characteristic. Here, a series of new dihydrobenzo[h]quinolines (h-DHBQs 4-1-34) and dihydrobenzo[f]quinolines (f-DHBQs 5a-e) were designed and synthesized by the 3CR to study their bioactivities as novel inhibitors against the influenza A (H1N1) virus. The structure-activity relationship (SAR) indicates that the antiviral activities of DHBQs depend on the combination of substituents and three of h-DHBQs (4-12, 4-25 and 4-27) show potent antiviral activity with IC50 = 2.52-3.79 µM. These potent h-DHBQs have low toxicity to MDCK and A549 cells (CC50 > 100 µM for 4-12 and > 50/100 µM for 4-25 and 4-27). The primary mechanism of the antiviral activities of DHBQs was studied using the most potent h-DHBQ 4-12, which indicated that 4-12 could efficiently inhibit virus-induced plaque formation and NP/PB2 protein expression in a dose-dependent way. DHBQs with simple synthetic method, useful AIE characteristic and antiviral activities are expected to be developed into potential inhibitors against influenza A virus, at the same time acting as chemical/biological fluorescent probe.

In situ synthesis and electrochemical performance of MoO3-x nanobelts as anode materials for lithium-ion batteries.

MoO3-x nanobelts with different concentrations of oxygen vacancies were synthesized by a one-step hydrothermal process. XPS test results show that oxygen vacancies are distributed from the exterior to the interior of the MoO3-x nanobelts. As an anode material for lithium-ion batteries, MoO3-x-10 releases excellent rate capacitance. It can maintain a high specific capacitance of about 500 mA h·g-1 at a high current density of 1000 mA·g-1. In the aspect of cycling stability, MoO3-x-10 can retain a high specific capacity of 641 mA h·g-1 after cycling for 50 times at 100 mA·g-1 and 420 mA h·g-1 after cycling for 100 times at 500 mA·g-1. The coexistence of oxygen vacancies and low-valence Mo ions is conducive to the intercalation/de-intercalation of Li ions and to promoting redox reactions. It has been proved to be a significantly effective way in which oxygen vacancies can improve the integrated performance of MoO3-x nanobelts as anode materials.

Effect of sulfur doping on structural reversibility and cycling stability of a Li2MnSiO4 cathode material.

Based on the existing calculation reports, sulfur doping is an effective approach to alleviate the structure collapse of Li2MnSiO4 during cycling. Herein, we investigate the feasibility and limitations of S doping in Li2MnSiO4 by experiment. In our work, the solid solubility of S is confirmed and exceeding the threshold results in MnS impurity. The existence state and site of the S element in a Li2MnSiO4 crystal structure is also confirmed. It is found that S doping significantly improves the structural reversibility and cycling stability. Compared with a pristine sample, a 1mol% S doped sample exhibits a much higher initial coulombic efficiency (88.3%), excellent capacity retention (98% at 10th cycles for instance) and enhanced rate performance. Moreover, the 1mol% S doped sample can retain a discharge capacity of 137 mA h g-1 after 30 cycles while the pristine sample only has 61.6 mA h g-1. This study confirms the effectivity of S doping in suppressing the structural distortion in Li2MnSiO4.