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本文讨论了24-羟基甘草内酯(1)甘草内酯乙酸酯(3)等甘草三萜类化合物的~(13)CNMR谱、对其化学位移进行了指定。结果表明,1和3均系18β-构型,可由C_(12)和C_(10)特征化学位移识别。这些化合物密集谱线的多重性由质子宽带去偶,单频偏共振去偶和PRFT(Partially Relaxed FT)谱比较分析完成。选择适当的脉冲间隔,可由PRFT谱方便地识别这些化合物的季碳,CH,CH_2和CH_3。
In this paper, ~ (13) CNMR spectra of glycyrrhizin triterpenoids such as 24-hydroxy licorithiolactone (1) glycyrrhizin acetate (3) are discussed and their chemical shifts are assigned. The results show that both 1 and 3 are 18β-configuration, which can be identified by C_ (12) and C_ (10) characteristic chemical shifts. The multiplicity of dense lines of these compounds is decoupled by proton broadband, and the single frequency partial resonance relaxation and even PRFT (Partially Relaxed FT) spectrum analysis is completed. By choosing the appropriate pulse interval, the quaternary carbon, CH, CH 2 and CH 3 of these compounds can be easily identified by PRFT spectra.