We report on a copper-catalyzed three-component reaction for the synthesis of disubstituted nicotinonitriles using 3-bromopropenals, benzoylacetonitriles, and ammonium acetate (NHOAc). The Knoevenagel-type condensation of 3-bromopropenals with benzoylacetonitriles gives δ-bromo-2,4-dienones that contain strategically placed functional groups that react with the ammonia generated to give the corresponding azatrienes. These azatrienes can then be transformed into trisubstituted pyridines under the reaction conditions via a reaction sequence involving 6π-azaelectrocyclization and aromatization.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
October 2019
Rehmannia glutinosa, a perennial herbaceous species, belongs to the family Scrophularia-ceae. As a staple medicinal material, its tuberous roots are highly valued in traditional Chinese medicine. However, R.
View Article and Find Full Text PDFPseudostellaria heterophylla is a perennial herbaceous plant in the family Caryophyllaceae. The tuberous roots of P. heterophylla are highly valued in traditional Chinese medicine and have a high market demand.
View Article and Find Full Text PDFBy using Biolog Ecoplate system, this paper studied the structure and functional diversity of soil microbial community under different vegetation types in Wuyishan National Nature Reserve, aimed to probe into the effects of vegetation type on the diversity of soil microbial community. The results showed that the soil chemical properties, soil enzyme activities, and average well color development (AWCD) were higher in natural forest than in planted forest, and were the lowest in abandoned field. The AWCD reflecting soil microbial activity and functional diversity was increased with increasing incubation time, but there existed significant differences among different vegetation types.
View Article and Find Full Text PDFObjective: In contrast to the newly-planted plants, through measuring and analyzing the chlorophyll content, photosynthetic characteristics, root activity and enzyme activity of Rehmannia glutinosa in growth stages, the differentiation manifestation of R. glutinosa physiological activity mediated by continuous cropping was studied.
Methods: SPAD-502 chlorophyll meter was used to measure chlorophyll content and LI-6400 portable photosynthetic apparatus to determine plant photosynthetic characteristics.