156474-22-5Relevant academic research and scientific papers
Polymer-supported ruthenium porphyrins: Versatile and robust epoxidation catalysts with unusual selectivity
Yu, Xiao-Qi,Huang, Jie-Sheng,Yu, Wing-Yiu,Che, Chi-Ming
, p. 5337 - 5342 (2000)
Carbonyl ruthenium(II) 5,10,15-tris(4-R-phenyl)-20-(4- hydroxyphenyl)porphyrins (R = Cl, Me) covalently attached to Merrifield's peptide resin were prepared. The catalyst with R = Cl was found to efficiently catalyze Cl2pyNO epoxidation of a wide variety of alkenes, including aromatic and aliphatic terminal alkenes, cis- and trans-stilbene, cyclohexene and cyclooctene, α,β-unsaturated ketones, conjugated enyne, glycal, and protected α-amino alkene. Unusual selectivities were observed for the epoxidations of 1,5-cyclooctadiene, cis-1-phenyl-3-penten-1-yne (9), 3,4,6-tri-O-acetyl-D-glucal (11), and 2-(Boc-amino)-1-phenylbut-3-ene (13), which feature a complete bisepoxide selectivity (1,5-cyclooctadiene), unprecedentedly high cis:trans ratio (9), and complete diastereoselectivity (11 and 13). The new heterogenized metalloporphyrin epoxidation catalysts are of high stability and reusability.
Diastereoselective epoxidation of allylically substituted alkenes using metalloporphyrin catalysts
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Page/Page column 8, (2008/06/13)
Diastereoselective epoxidation of allylically substituted alkenes using metalloporphyrins as catalyst provides high trans-selectivities (i.e., trans-:cis-epoxide ratio). A diversity of cycloalkenes bearing different allylic substituents are shown to be efficiently epoxidized to afford the corresponding trans-epoxides with excellent trans-selectivities (up to >98%) and good yields (up to 99%). Acyclic allylic alkenes bearing different allylic substituents are efficiently epoxidized to afford the corresponding erythro-epoxides with good erythro-selectivities. The metalloporphyrin-catalyzed reactions exhibit up to 20 times higher trans-selectivities than the conventional method using m-chloroperoxybenzoic acid as oxidant.
Stereochemical analysis of (hydroxyethyl)urea peptidomimetic inhibitors of γ-secretase
Bakshi, Pancham,Wolfe, Michael S.
, p. 6485 - 6489 (2007/10/03)
(Hydroxyethyl)urea peptidomimetics systematically altered at positions P2-P3′ with hydrophobic D-amino acids were synthesized. An all D-amino acid containing analogue was identified that effectively blocked γ-secretase activity in a cell-free system (IC50 = 30 nM). Systematic alteration of the stereocenters of a potent compound revealed interdependence between the various positions. Although typically less potent than their L-peptidomimetic counterparts, selected all D-amino acid containing analogues were equipotent to their counterparts in a cell-based assay when incubated for extended times.
Cyclic hydrazine compounds
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, (2008/06/13)
This invention relates to substituted cyclic carbonyls and derivatives thereof useful as retroviral protease inhibitors to pharmaceutical compositions comprising such compounds, and to methods of using these compounds for treating vital infection.
