Constantinou-Kokotou V, Kokotos G
Chemistry Laboratory, Agricultural University of Athens, Greece.
Amino Acids. 1999;16(3-4):273-85. doi: 10.1007/BF01388172.
Lipidic alpha-amino acids (LAAs) are a class of compounds combining structural features of amino acids with those of fatty acids. They are non-natural alpha-amino acids with saturated or unsaturated long aliphatic side chains. Synthetic approaches to optically active LAAs and lipidic 2-amino alcohols (LAALs) are summarized in this review. A general approach to enantioselective synthesis of saturated LAAs is based on the oxidative cleavage of 3-amino-1,2-diols obtained by the regioselective opening of enantiomerically enriched long chain 2,3-epoxy alcohols. Unsaturated LAAs are prepared in their enantiomeric forms by Wittig reaction via methyl (S)-2-di-tert-butoxycarbonylamino-5-oxo-pentanoate. This key intermediate aldehyde is obtained by selective reduction of dimethyl N,N-di-Boc glutamate with DIBAL. (R) or (S) LAALs may be prepared starting from D-mannitol or L-serine. LAAs are converted into LAALs by chemoselective reduction of their fluorides using sodium borohydride with retention of optical purity. Replacement of the hydroxyl group of LAALs by the azido group, followed by selective reduction leads to unsaturated optically active lipidic 1,2-diamines.
脂族α-氨基酸（LAAs）是一类将氨基酸的结构特征与脂肪酸的结构特征结合起来的化合物。它们是具有饱和或不饱和长脂肪族侧链的非天然α-氨基酸。本文综述了光学活性LAAs和脂族2-氨基醇（LAALs）的合成方法。饱和LAAs对映选择性合成的一般方法是基于对映体富集的长链2,3-环氧醇区域选择性开环得到的3-氨基-1,2-二醇的氧化裂解。不饱和LAAs通过经由甲基（S）-2-二叔丁氧羰基氨基-5-氧代戊酸酯的维蒂希反应以对映体形式制备。这个关键的中间体醛是通过用二异丁基氢化铝选择性还原二甲基N，N-二叔丁氧羰基谷氨酸得到的。（R）或（S）LAALs可以从D-甘露糖醇或L-丝氨酸开始制备。通过用硼氢化钠化学选择性还原LAAs的氟化物并保持光学纯度，可将LAAs转化为LAALs。用叠氮基取代LAALs的羟基，然后进行选择性还原，得到不饱和光学活性脂族1,2-二胺。
