Synthesis of 4-(2-hydroxyaryl)-3-nitro-4H-chromenes
摘要:
A combinatorial library of 4-(2-hydroxyaryl)-3-nitro-4H-chromenes was synthesized in high yield by C4-SMe substitution in N-alkyl/phenyl 4-(methylthio)-3-nitro-4H-chromen-2-amines with a variety of phenols. The reaction always provided C2 substitution in the phenol ring, dictated by hydrogen bond interactions between the phenolic hydroxyl group and the nitro group in 3-nitro-4H-chromenes. Reduction of the nitro group with concomitant hydrolysis of the enamine in 4-(2-hydroxyaryl)-3-nitro-4H-chromenes with Zn, Ac(2)O in AcOH furnished hybrid amino-acid lactone incorporating ortho-tyrosine and phenyl alanine moieties. (C) 2011 Elsevier Ltd. All rights reserved.
Synthesis of 4-(2-hydroxyaryl)-3-nitro-4H-chromenes
作者:H. Surya Prakash Rao、K. Geetha、M. Kamalraj
DOI:10.1016/j.tet.2011.08.045
日期:2011.10
A combinatorial library of 4-(2-hydroxyaryl)-3-nitro-4H-chromenes was synthesized in high yield by C4-SMe substitution in N-alkyl/phenyl 4-(methylthio)-3-nitro-4H-chromen-2-amines with a variety of phenols. The reaction always provided C2 substitution in the phenol ring, dictated by hydrogen bond interactions between the phenolic hydroxyl group and the nitro group in 3-nitro-4H-chromenes. Reduction of the nitro group with concomitant hydrolysis of the enamine in 4-(2-hydroxyaryl)-3-nitro-4H-chromenes with Zn, Ac(2)O in AcOH furnished hybrid amino-acid lactone incorporating ortho-tyrosine and phenyl alanine moieties. (C) 2011 Elsevier Ltd. All rights reserved.