A new route to hydrophobic amino acids using copper-promoted reactions of serine-derived organozinc reagents
作者:Hervé J. C. Deboves、Urszula Grabowska、Adriana Rizzo、Richard F. W. Jackson
DOI:10.1039/b007032g
日期:——
Copper-catalysed reaction of the serine-derived zinc reagent 1 with allylic electrophiles gives products arising formally from both SN2 and SN2′ pathways. These constitutional isomers can be separated, either directly, or in the case of (2S)-2-tert-butoxycarbonylamino-6-methylhept-5-enoic acid methyl ester (11) and (2S)-2-tert-butoxycarbonylamino-4,4-dimethylhex-5-enoic acid methyl ester (12) by selective epoxidation of 11. Hydrogenation of the double bond, followed by protecting group manipulation, allows the synthesis of the Fmoc-protected amino acids 3–7 ready for automated peptide synthesis.
铜催化的丝氨酸衍生的锌试剂1与烯丙基亲电试剂反应,生成的产品源于形式上的SN2和SN2'途径。这些构造异构体可以直接分离,或者在(2S)-2-叔丁氧羰基氨基-6-甲基庚-5-烯酸甲酯(11)和(2S)-2-叔丁氧羰基氨基-4,4-二甲基己-5-烯酸甲酯(12)的情况下,通过选择性环氧化11来分离。双键的氢化,随后保护基团的调控,允许合成Fmoc保护的氨基酸3-7,准备用于自动化多肽合成。