An efficient method for the synthesis of N-sec-alkylpyrazoles through a base-promoted cascade cyclization/Michael addition reaction of α,β-unsaturated N-tosylhydrazones with ortho-hydroxybenzyl alcohols has been developed. The desired products containing di- or triaryl groups at the same carbon atom were afforded in good to excellent yields with excellent regioselectivities (>20 : 1). Moreover, a three-component reaction of ortho-hydroxybenzyl alcohols, α,β-unsaturated N-tosylhydrazones and saturated N-tosylhydrazones also took place to afford pyrazoles in good yields.
View Article and Find Full Text PDFHibernation is an effective energy conservation strategy that has been widely adopted by animals to cope with unpredictable environmental conditions. The liver, in particular, plays an important role in adaptive metabolic adjustment during hibernation. Mammalian studies have revealed that many genes involved in metabolism are differentially expressed during the hibernation period.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
October 2008
The contents of trace elements, including copper, zinc, iron, magnesium, calcium, chromium, lead, molybdenum, manganese, and cadmium in Chinese traditional herb S. miltiorrhiza and its relative species such as S. miltiorrhiza f.
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