Synthesis of Dihydroxyethylene Isosteres of Dipeptides. 1. Enantiomerically and Diastereomerically Pure 2-Alkyl-5-amino-3-dimethylphenylsilyl-4-octanolides from (<i>S</i>)-<i>N,N</i>-Dibenzylleucinal
作者:Frank Rehders、Dieter Hoppe
DOI:10.1055/s-1992-26247
日期:——
5-Dibenzylamino-3-dimethylphenylsilyl-4-octanolides are prepared via homoenolate addition of (S)-N,N-dibenzylleucinal [(S)-2-dibenzylamino-4-methylpentanal] and metalated 3-dimethylphenylsilyl-2-propenyl N,N-diisopropylcarbamate, followed by oxidative lactonization. Subsequently, alkyl groups are introduced stereoselectively to the 2-position by means of enolate methodology to yield the title compounds, which are valuable intermediates in the synthesis of dipeptide isosteres.
5-二苄基氨基-3-二甲基苯基硅烷基-4-辛醇是通过(S)-N,N-二苄基亮氨酸((S)-2-二苄基氨基-4-甲基戊醛)和金属化的3-二甲基苯基硅烷基-2-丙烯基N,N-二异丙基氨基甲酸酯的同烯醇加成,然后进行氧化环化反应制备的。随后,通过烯醇方法将烷基选择性地引入2位,得到标题化合物,这是合成二肽同分异构体的有价值的中间体。