RESUMO
A total synthesis of the caribenol A (1), a novel natural product with an intriguing tetracyclic framework, has been achieved. The synthesis features an intramolecular Diels-Alder (IMDA) reaction for the facile construction of the tricyclic [5-7-6] skeleton of caribenol A (1) and a biomimetic oxidation reaction for the formation of the 2-hydroxyfuran-2(5H)-one motif of caribenol A (1) as key steps. This synthetic approach also reveals that the sp(2) carbon at C(2) in substrate 8 is a critical factor for the formation of the tricyclic [5-7-6] skeleton in 7.
Assuntos
Diterpenos/síntese química , Cristalografia por Raios X , Ciclização , Diterpenos/química , Modelos Moleculares , Conformação MolecularRESUMO
A unified strategy toward the asymmetric total synthesis of carbenol A is reported, featuring intramolecular Diels-Alder (IMDA) and biomimetic oxidation reactions as key steps.
Assuntos
Antibacterianos/síntese química , Diterpenos/síntese química , Antibacterianos/química , Cristalografia por Raios X , Diterpenos/química , Modelos Moleculares , Conformação Molecular , EstereoisomerismoRESUMO
Institute of Materials, Chinese Academy of Engineering Physics, Jiangyou 621908, P. R. China To improve the stability of organic-inorganic hybrid perovskite, cesium-containing methylammonium lead iodide perovskite have been synthesized by one-step solution deposition. With the increasing of Cs+ doping concentration, direct optical band gap of perovskite was increases, while defects and roughness of perovskite thin films were gradually augmented. A certain amount of Cs+ incorporated in perovskite absorb layer could improve power conversion efficiency through the enhancing of open circuit voltage and fill factor. However, excessive Cs+ doping concentration results in the reduced of short-circuit current and fill factor, which reduced power conversion efficiency. The optimized ratio 10% Cs+ doping achieved the highest power conversion efficiency (16.84%).