Conformational Study and Enantioselective, Regiospecific Syntheses of Novel Aminoxy <i>trans</i>-Proline Analogues Derived from an Acylnitroso Diels−Alder Cycloaddition
作者:Brock T. Shireman、Marvin J. Miller、Marco Jonas、Olaf Wiest
DOI:10.1021/jo010284l
日期:2001.9.1
temperature 1H NMR studies. The syntheses of the acylnitroso-derived peptides utilized two methods to selectively functionalize either of two chemically similar esters in the acylnitroso-derived amino acids. A novel transpeptidation of the amino acid that controlled the absolute stereochemistry in the acylnitroso Diels-Alder cycloaddition took advantage of an activated aminoxy amide linkage to control
脯氨酸酰胺键的顺式/反式异构化在生物学过程中具有许多含义。代表性的衍生自环戊二烯的酰基亚硝基衍生的脯氨酸类似物的构象仅在CD2Cl2中以E或反式构象存在。除低温1H NMR研究外,在理论上B3LYP / 6-31G的水平上,使用COSMO自洽反应场计算确定了在能量上有利的构象。酰基亚硝基衍生的肽的合成利用两种方法选择性地官能化酰基亚硝基衍生的氨基酸中的两种化学相似的酯中的任一种。控制酰基亚硝基Diels-Alder环加成反应中绝对立体化学的氨基酸的新型转肽利用了活化的氨氧基酰胺键来控制区域化学。或者,外消旋二甲基酯的对映选择性和区域特异性酶促拆分提供了新的氨氧基酸。