NMR Characteristics and Conformational Analysis of Oxiracetam

Abstract

Abstract:

Oxiracetam is often used as a nootropic agent. In this study, the NMR characteristics and conformation of oxiracetam were investigated. It was shown that the protons on the sidechain methylene group are magnetic nonequivalent because of the anisotropy effect of pyrrolidine ring. H₆and H₃ showed long-range coupling, due to the partial double-bond character of the amide bond on the pyrrolidine ring. Pyrrolidine ring favored envelope conformation. Hindered internal rotation of another amide bond on the side chain was also analyzed.

Key words: NMR, conformation, 2D NMR, VT NMR, Oxiracetam, long-range coupling

CLC Number:

O641

ZHU Chuan-Jun, JIN Xiao-Feng, JIANG Biao, CUI Yu-Xin. NMR Characteristics and Conformational Analysis of Oxiracetam[J]. Chinese Journal of Magnetic Resonance, 2010, 27(4): 609-616.

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