文献类型：期刊文献

中文题名：Methyl Group in Isocopalane Derivative Showed an Unusual Negative 1H NMR Chemical Shift

作者：Xiong Xiao[1];Tianqi Chen[1];Fengfeng Zhang[1];Jiagao Cheng[1];Peiying Wu[3];Jiangmeng Ren[1];Bubing Zeng[1,2]

机构：[1]Shanghai Key Laboratory of New Drug Design,School of Pharmacy,East China University of Science and Technology,Shanghai 200237,China;[2]Key Laboratory of Synthetic Chemistry of Natural Substances,Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032,China;[3]School of Pharmacy,Shanghai University of Traditional Chinese Medicine,Shanghai 201203,China

年份：2015

卷号：33

期号：6

起止页码：643

中文期刊名：Chinese Journal of Chemistry

外文期刊名：中国化学（英文版）

收录：CSTPCD;;Scopus;CSCD:【CSCD2015_2016】；PubMed;

基金：supported by National Natural Science Foundation of China(No.21302053);Science and Technology Commission of Shanghai Mu-nicipality(No.14DZ1900102);the Fundamental Research Funds for the Central University(No.WY1113007)。

语种：英文

中文关键词：shielding effect;diterpenoid;dihydropyrazole;negative chemical shift;computational study

摘要：An unusual negative 1H NMR chemical shift of methyl group was discovered in condensation product of isoco-palane diterpenoid with p-toluenesulfonyl hydrazide.2D NMR,computational studies and single-crystal X-ray dif-fraction analysis showed that the C-20 methyl group was shielded.