6-Chloro-2,4-dinitrophenylhydrazine as a useful crystalline agent for the determination of absolute configuration
作者:Yasushi Kawai、Motoko Hayashi、Norihiro Tokitoh
DOI:10.1016/s0040-4039(01)02159-1
日期:2002.1
For the determination of absoluteconfiguration, we designed and synthesized some hydrazines as crystalline auxiliaries having a heavy atom, and found that 6-chloro-2,4-dinitrophenylhydrazine is a useful crystalline agent for chiral carbonyl compounds. The absoluteconfigurations of chiral hydrazones prepared from the hydrazine and chiral ketones were determined by X-ray crystallographic analysis.
Hydrogen transfer pathways of the asymmetric reduction of α,β-unsaturated ketone mediated by baker’s yeast
作者:Yuan Chu、Ben Li Zhang、Virginie Silvestre、Jin Pei Cheng
DOI:10.1016/j.bioorg.2006.04.002
日期:2006.6
the quantity of yeast. When the amount of yeast is very large, the enzymes use preferentially certain unidentified substance stored in the yeast cells rather than the added glucose as electrondonor. In this case, the hydrogen transferred by the cofactor is mainly of water origin. When the yeast amount is low, the added glucose is more efficiently used by the enzymes as electrondonor and its hydrogen