Synthesis of tubuphenylalanine and epi-tubuphenylalanine via regioselective aziridine ring opening with carbon nucleophiles followed by hydroboration-oxidation of 1,1-substituted amino alkenes
作者:Ramesh B. Reddy、Premansh Dudhe、Priyanka Chauhan、Sagnik Sengupta、Venkatesh Chelvam
DOI:10.1016/j.tet.2018.10.024
日期:2018.11
An efficient synthesis of N-Boc-tubuphenylalanine benzyl ester (N-Boc-Tup-OBn, 1a) and N-Boc-epi-tubuphenylalanine benzyl ester (N-Boc-epi-Tup-OBn, 1b) is reported herein. Regioselective aziridine 4 ring opening with carbon nucleophiles followed by hydroboration of 1,1-substituted aminoalkene 3 using 9-BBN and subsequent oxidation in an alkaline medium are used as the key steps to provide N-tosyl 1
的有效合成Ñ -Boc-tubuphenylalanine苄酯(Ñ -Boc-托普-OBN,1A)和Ñ -Boc-外延-tubuphenylalanine苄基酯(Ñ -Boc-外延-Tup-OBN,1B)在本文中报道。提供碳-亲核试剂的区域选择性氮丙啶4开环,然后使用9-BBN将1,1-取代的氨基烯烃3加氢硼化,然后在碱性介质中氧化,是提供N-甲苯磺酰基1,4-氨基醇的关键步骤。1,4-氨基醇成功转化为所需产物,1a的总收率为23%在连续8个步骤中1b分别占11%。