Chin. J. Org. Chem. ›› 2011, Vol. 31 ›› Issue (04): 538-543. Previous Articles     Next Articles

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S-[2-(叔丁氧羰基氨基)乙基]-3-苯基丙酸硫酯类化合物脱除Boc保护基的反应研究

贾尧玲1,王洋*,1,2   

  1. (1复旦大学药学院药物化学教研室 上海 201203)
    (2中国科学院上海药物研究所新药研究国家重点实验室 上海 201203)
  • 收稿日期:2011-01-28 修回日期:2011-03-02 发布日期:2011-03-10
  • 通讯作者: 王洋 E-mail:wangyang@shmu.edu.cn

Study on the Deprotection of Boc Group of S-2-(tert- Butoxycarbonylamino)ethyl 3-Phenylpropanethioates

Jia Yaoling1 Wang Yang*,1,2   

  1. (1 Department of Medicinal Chemistry, School of Pharmacy, Fudan University, Shanghai 201203)
    (2 State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203)
  • Received:2011-01-28 Revised:2011-03-02 Published:2011-03-10
  • Contact: Yang WANG E-mail:wangyang@shmu.edu.cn

S-2-(tert-Butoxycarbonylamino)ethyl 3-phenylpropanethioates (3a3d) were synthesized in 79%~92% yields through the esterification of substituted 3-phenylpropanoic acids (1a1d) and methyl N-(tert-butoxycarbonyl)-L-cysteine (2) by using bis(2-oxo-3-oxazolidinyl)phosphinic chloride (BOP-Cl) as the condensation agent. The deprotection of Boc group of 3a3d by trifluoroacetic acid (TFA) gave not only normal deprotecting products 4a4d but also 2-substituted thiazolines 5a5d which were obtained by intramolecular dehydration of the corresponding 4a4d, whereas the deprotection of Boc group of S-2-(tert-butoxycarbonylamino)ethyl 3-phenylpropenethioates (3e3f) afforded only deprotecting products 4e4f under the same condition due to their double bond rigid structures. 4a4d and 5a5d could be obtained in high yields (85%~91% and 86%~89%) respectively by optimizing reaction conditions on the amount of TFA, the reaction temperature and time, which provided a facile and effective method to synthesize 2-substituted thiazolines.

Key words: S-2-(tert-butoxycarbonylamino)ethyl 3-phenylpropanethioate, thiazoline, Boc group, trifluoroacetic acid (TFA)