killing by peptidomimetics while avoiding toxicity to normal cells. The influences of type of amino acid and substituent, length of substituent, and stereochemistry of amino acids on antibacterial activity and cytotoxicity of peptidomimetics were systematically investigated. The results indicate that this series of cationic peptidomimetics derived from amino acids display antitumor activity and may be
Synthesis of Highly Substituted Imidazolidine-2,4-dione (Hydantoin) through Tf<sub>2</sub>O-Mediated Dual Activation of Boc-Protected Dipeptidyl Compounds
作者:Hui Liu、Zhimin Yang、Zhengying Pan
DOI:10.1021/ol502900j
日期:2014.11.21
Highly substituted chiral hydantoins were readily synthesized from simple dipeptides in a single step under mild conditions. This reaction proceeded through the dual activation of an amide and a tert-butyloxycarbonyl (Boc) protecting group by Tf2O-pyridine. This method was successfully applied in the preparation of a variety of biologically active compounds, including drug analogs and natural products
A Chiral Ag-Based Catalyst for Practical, Efficient, and Highly Enantioselective Additions of Enolsilanes to α-Ketoesters
作者:Laura C. Akullian、Marc L. Snapper、Amir H. Hoveyda
DOI:10.1021/ja061166o
日期:2006.5.1
A Ag-based chiral catalyst promotes efficient and highlyenantioselective aldol additions of ketone-derived enolsilanes to alpha-ketoesters in the presence of a readily available amino acid-based ligand and commercially available AgF2. alpha-Ketoester substrates may bear alkyl, alkenyl, and aryl substituents; reactions proceed to >98% conversion to afford the desired tertiary alcohols in 61->98% isolated
在容易获得的基于氨基酸的配体和市售的 AgF2 存在下,基于 Ag 的手性催化剂促进了酮衍生的烯醇硅烷向 α-酮酯的高效和高度对映选择性羟醛加成。α-酮酯底物可带有烷基、烯基和芳基取代基;反应进行到 >98% 的转化率,以 61->98% 的分离产率和 60-96% 的 ee 得到所需的叔醇。与之前报道的方法相比,在空间要求严格的底物上观察到了最高的对映选择性,并且反应可以在未蒸馏的溶剂中、在空气中使用低至 1 mol% 的催化剂进行。
Hexylsilane-mediated direct amidation of amino acids with a catalytic amount of 1,2,4-triazole
In this study, we report aminoacidamidation using hexylsilane and a catalytic amount of 1,2,4-triazole. The conventional protection/deprotection method for the α-amino group of aminoacids is not required. The corresponding α-amino amides were obtained in moderate to good yields with low to no racemization.
Enantioselective Synthesis of Arylamines Through Zr-Catalyzed Addition of Dialkylzincs to Imines. Reaction Development by Screening of Parallel Libraries
作者:James R. Porter、John F. Traverse、Amir H. Hoveyda、Marc L. Snapper