Sequential "Bis-Michael" Additions of Dienolates with C60: Rapid Access to Sterically Congested Buckminsterfullerene Derivatives with Defined Stereochemistry
Sequential "Bis-Michael" Additions of Dienolates with C60: Rapid Access to Sterically Congested Buckminsterfullerene Derivatives with Defined Stereochemistry
Expedient Synthesis of Highly Substituted Pyrroles via Tandem Rearrangement of α-Diazo Oxime Ethers
作者:Yaojia Jiang、Wei Chuen Chan、Cheol-Min Park
DOI:10.1021/ja300552c
日期:2012.3.7
An efficient rhodium-catalyzed synthesis of 2H-azirines and pyrroles has been developed. Novel rearrangement of α-oximino ketenes derived from α-diazo oxime ethers provides 2H-azirines bearing quaternary centers and allows for subsequent rearrangement to highly substituted pyrroles in excellent yields.
Stereoselective addition of organometallic reagents to β-hydroxyketones
作者:José Luis Garcia Ruano、Amelia Tito、Rafael Culebras
DOI:10.1016/0040-4020(95)01048-3
日期:1996.2
Reactions of several β-hydroxyketones with different methylation reagents are reported. The de's are moderated or good (40–75%) and slightly change with the relative steric size of the R groups at the starting hydroxyketone. The syn-diols are predominant in reactions with Me3Al/ZnBr2 and MeLi/Me3Al, whereas the anti-diols are the major ones with MeLi/ZnBr2. The method has been used to synthesize optically
On the diastereoselectivity of cyanide addition to β-hydroxyketones: One-pot synthesis of syn β-hydroxycyanohydrins and anti 2,4-dihydroxyamides
作者:Manohar Singh Batra、Francisco J. Aguilar、Ernesto Brunet
DOI:10.1016/s0040-4020(01)85299-6
日期:——
Optimizing the Binding of Fullerene Inhibitors of the HIV-1 Protease through Predicted Increases in Hydrophobic Desolvation
作者:Simon H. Friedman、Padma S. Ganapathi、Yves Rubin、George L. Kenyon
DOI:10.1021/jm970689r
日期:1998.6.1
We have developed and applied a computational strategy to increase the affinity of fullerene-based inhibitors of the HIV protease. The result is a similar to 50-fold increase in affinity from previously tested fullerene compounds. The strategy is based on the design of derivatives which may potentially increase hydrophobic desolvation upon complex formation, followed by the docking of the hypothetical derivatives into the HIV protease active site and assessment of the model complexes so formed. The model complexes are generated by the program DOCK and then analyzed for desolvated hydrophobic surface. The amount of hydrophobic surface desolvated was compared with a previously tested compound, and if this amount was significantly greater, it was selected as a target. Using this approach, two targets were identified and synthesized, using two different synthetic approaches: a diphenyl C-60 alcohol (5) based on a cyclopropyl derivative of Bingel (Chem. Ber. 1993, 226, 1957-1959) and a diisopropyl cyclohexyl C-60 alcohol (4a) as synthesized by Ganapathi et al. (J. Org. Chem. 1995, 60, 2954-2955). Both showed tighter binding than the originally tested compound (diphenethylaminosuccinate methano-C-60, K-i = 5 mu M) with K-i values of 103 and 150 nM, respectively. In addition to demonstrating the utility of this approach, it shows that simple modification of fullerenes can result in high-affinity ligands of the HIV protease, for which they are highly complementary in structure and chemical nature.
Highly diastereoselective addition of cyanide to β-hydroxyketones
作者:Ernesto Brunet、Manohar Singh Batra、Francisco J. Aguilar、José Luis García Ruano
DOI:10.1016/s0040-4039(00)92403-1
日期:1991.9
The addition of cyanide with KCN/ZnI2/TMSCN to beta-hydroxyketones (R1-CHOH-CO-R2, R1 = i-Pr, R2 = Me, Et, i-Bu, i-Pr, t-Bu, R1 = Et, R2 = t-Bu and R1 = Bn, Ph, R2 = i-Bu) produced syn beta-hydroxycyanohydrins in 95% d.e.