RESUMEN
Toward the total synthesis of a novel grayanoid, mollanol A, we developed a concise convergent strategy based on a formal [3 + 2] cyclization initiated by the Prins reaction. In this key intermolecular reaction between an unprotected hydroxyaldehyde and activating-group-free olefins, two chiral carbons and one densely substituted tetrahydrofuran ring were constructed stereoselectively.
RESUMEN
Based on the high-resolution coal-fired power plant emission database, GEOS-Chem Adjoint, a global-regional nested atmospheric chemistry model and its adjoint were applied to analyze PM2.5-related premature deaths caused by the power sector in six grid regions of China due to air pollutant emissions and subsequent pollution. The results show that power sector-related PM2.5 pollution caused 106000 (95% CI:68000-132000) premature deaths in 2010, accounting for 9.8% of China's anthropogenic PM2.5-related premature deaths. The health loss intensity (defined as number of premature deaths caused by a unit of power generation) of small and old units is significantly higher than that of large and new units:units with a capacity below 100 MW reach 62 people·(TW·h)-1, 2.8 times that of units with a capacity above 600 MW. Similarly, the health loss intensity of units older than thirty years is 58 people·(TW·h)-1, 2.1 times that of new units. From the perspective of regional grids, the health impact index of Central China is relatively large, reaching 77 people·(TW·h)-1. Further analysis reveals that transregional power transmission led to a net increase of 680 premature deaths compared with the scenario without transmission in 2010. Our study implies that China should accelerate the pace of phasing out small and old units and optimize the power transmission distribution between grid regions to reduce the overall level of pollution and health losses.
Asunto(s)
Contaminación del Aire/efectos adversos , Carbón Mineral , Mortalidad , Centrales Eléctricas , Contaminantes Atmosféricos , China , Humanos , Material Particulado/efectos adversosRESUMEN
A three dimensional (3D) chemical feature based pharmacophore model was developed for selective histone deacetylase 1 (HDAC1) inhibitors, which provides an efficient way to discuss the isoform selectivity of HDAC inhibitors. In contrast to the classical pan-HDAC pharmacophore, two hydrophobic features (HY and HYAr2) were found in the chemical feature based pharmacophore model, which might be responsible for the selectivity of HDAC1 inhibitions. Molecular docking also highlighted the two hydrophobic features, which are located in the internal cavity adjacent to the active site. The results contribute to our understanding of the molecular mechanism underlying the selectivity of HDAC1 inhibitors and suggest a possible target region to design novel selective HDAC1 inhibitors.