Asymmetric transfer hydrogenation using amino acid derivatives; further studies and a mechanistic proposal
摘要:
A series of investigations into the use of amino acid derivatives for the asymmetric catalysis of the transfer hydrogenation of ketones are presented. Based on the results observed, a mechanistic suggestion for the origin of the ellantioselective induction is proposed. (c) 2005 Elsevier Ltd. All rights reserved.
Rhodium-Catalyzed Asymmetric Transfer Hydrogenation of Aryl Alkyl Ketones Employing Ligands Derived from Amino Acids
作者:Jenny Wettergren、Alexey B. Zaitsev、Hans Adolfsson
DOI:10.1002/adsc.200700345
日期:2007.12.10
The combination of (pentamethylcyclopentadienyl)rhodium dichloride dimer [RhCl2Cp*}2] and pseudodipeptide ligands, formed from N-Boc protected amino acids and amino alcohols, resulted in efficient and selective catalysts for the asymmetric transfer hydrogenation of ketones in 2-propanol. A number of different secondary alcohols was obtained in high yields and in excellent enantioselectivity using
Synthesis and characterization of Co(<scp>ii</scp>) and Fe(<scp>ii</scp>) peptide conjugates as hydrolytic cleaving agents and their preferential enantiomeric disposition for CT-DNA: structural investigation of <scp>l</scp>-enantiomers by DFT and molecular docking studies
Synthesis, characterization and in vitro DNA binding studies of tin(IV) complexes of tert-butyl 1-(2-hydroxy-1-phenylethylamino)-3-methyl-1-oxobutan-2-yl carbamate
作者:Farukh Arjmand、Jamsheera A.
DOI:10.1016/j.jorganchem.2011.08.009
日期:2011.11
Tin(IV) complexes 1(a and b) and 2(a and b) of valine derived peptide derivatives were synthesized and characterized on the basis of elemental analysis, IR, (1) H, C-13, Sn-119 NMR, ESI-MS spectra and molar conductance measurements. The C-Sn-C angle was estimated from C-I3 and H-1 NMR data (1)J(Sn-119, C-I3) = 623 Hz; solution (2)J(Sn-119, H-1) = 93.04 Hz to be 149.9 degrees. In vitro binding studies of complexes 1 and 2 under physiological conditions at room temperature with CT-DNA were carried out employing UV-visible, fluorescence, circular dichroism and viscometric studies. The binding affinity of the complexes was quantified by calculating the K-b values and it follows the order 2a > 1a > 2b > 1b. To further examine the specific mode of binding, the interaction of complexes 2(a and b) were carried out with 5'GMP and 5'TMP by using absorption and NMR (H-1, P-31) spectroscopy. The supercoiled pBR322 plasmid DNA cleavage activity of the complexes was ascertained by gel electrophoresis assay. The complexes cleave supercoiled pBR322 plasmid DNA efficiently into its nicked form at micromolar concentrations. (C) 2011 Elsevier B. V. All rights reserved.