ABSTRACT
Considering the millions of COVID-19 patients worldwide, a global critical challenge of low-cost and efficient anti-COVID-19 drug production has emerged. Favipiravir is one of the potential anti-COVID-19 drugs, but its original synthetic route with 7 harsh steps gives a low product yield (0.8%) and has a high cost ($68 per g). Herein, we demonstrated a low-cost and efficient synthesis route for favipiravir designed using improved retrosynthesis software, which involves only 3 steps under safe and near-ambient air conditions. A yield of 32% and cost of $1.54 per g were achieved by this synthetic route. We also used the same strategy to optimize the synthesis of sabizabulin. We anticipate that these synthetic routes will contribute to the prevention and treatment of COVID-19.
ABSTRACT
This article discussed air quality changes in the Beijing-Tianjin-Tangshan (BTT) region. The air quality index (AQI) values, and the concentrations of PM2.5, PM10, SO2, CO, NO2, and O-3 in the BTT region during the COVID-19 outbreak in 2020 were, respectively, 79.4, 47.2 mu g m(-3), 73.4 mu g m(-3), 10.3 mu g m(-3), 0.87 mg m(-3), 33.6 mu g m(-3), and 90.7 mu g m(-3). However, they were, respectively, 102.7, 61.4 mu g m(-3), 121.0 mu g m(-3), 9.0 mu g m(-3), 0.88 mg m(-3), 40.1 mu g m(-3), and 84.0 mu g m(-3) during the same period in 2021, which is an increase of 29.2%, 30.1%, 64.8%, -12.9%, 1.94 %, 19.5%, and -7.4% compared with the values in 2020. The combined proportions of grade I and grade II during the COVID-19 outbreak in 2020 were 16.7% higher than those in the same period in 2021, so the air quality has deteriorated rapidly from 2020 to the post-COVID era in 2021. The possible reasons for poorer air quality are that the frequency of dusty weather and air pollutant discharge has increased, and meteorological conditions have been relatively unfavorable. The average AQI values, and concentrations of PM2.5, PM10, SO2, CO, NO2, and O-3 during the post-COVID period in 2021 respectively decreased by 14.8%, 29.0%, 14.6%, 22.5%, 37.4%, 14.8%, and 8.7%, compared with those in 2020. It is also worth noting that all the changes in air pollution during the post-COVID era have been consistent. The combined proportions of grade I and grade II during post-COVID period in 2021 were 18.4% higher than those during the same period of 2020, which indicates that the air quality during post-COVID 2021 has obviously improved compared with those in the same period of 2020. The possible reasons are a series of clean air policies and clean air actions, as well as favorable atmospheric diffusion conditions. These results indicate that clean air policies play a very important role in improving air quality.
ABSTRACT
This study explored the first-person lived experiences of 2 nurses and 2 doctors combating coronavirus disease 2019 (COVID-19) in Wuhan, China. The in-depth interviews indicated that frontline healthcare professionals were at high risk of developing symptoms of fear, anxiety, depression, stress, loneliness, and burnout. The fear of being infected and the heavy workload in the isolation ward are the main risk factors for frontline health workers' psychological problems. Comprehensive assistance and social support must be provided in order to resolve their mental health issues.