摘要
使用高效液相色谱-多级质谱法(HPLC-ESI/MSn)研究了土荆皮二萜的ESI/MSn裂解行为,并对土荆皮中的二萜类化合物进行了定性分析。土荆皮二萜的特征裂解是内酯环和C4-O键的断裂。此外,C-18、C-7和C-8位取代基的离去在多级质谱(MSn,n=3～4)中也可观察到。对于C-4位乙酰氧基取代的二萜,[M+Na-60]+和[M-H-104]-分别是正、负离子模式下二级质谱的基峰。对于C-4位羟基取代的二萜,[M+Na-44]+和[M-H-62]-分别是正、负离子模式下二级质谱的基峰。对于C-18位葡萄糖苷化或酯化的二萜,[M+Na-44]+是正离子模式下二级质谱的基峰。利用上述裂解规律,使用LC-MS方法在正离子模式下鉴定了土荆皮甲醇-水(6∶4)提取物中的二萜类化合物,共有9个二萜被鉴定或初步推测,其中一个是首次报道的化合物。所述方法可用于土荆皮的灵敏快速定性分析。
Fragmentation behavior of diterpenoids was investigated by ESI/MSn and the qualitative analysis of diterpenoids in the bark of Pseudolarix kaempferi was performed using high-performance liquid chromatography/ multi-stage mass spectrometry（HPLC-ESI/MSn）.The characteristic fragmentation behaviors of the diterpenoids are the cleavages of the lactone ring and C4-O bond.Furthermore,the eliminations of substituent groups at C-18,C-7 and C-8 can also be observed in the MSn（n=3-4） spectra.For C-4 acetoxy subsititued diterpenoids,[M＋Na-60]＋ and [M-H-104]- are the base peaks of MS2 spectra in the positive and negative ionization modes,respectively.For C-4 hydroxyl subsititued diterpenoids,[M＋Na-44]＋ and [M-H-62]- are the base peaks of MS2 in the positive and negative ionization modes,respectively.For C-18 glucosylated or esterized diterpenoids,[M＋Na-44]＋ is the base peak of MS2 spectra in positive ionization mode.These fragmentation rules were successfully exploited in the identification of diterpenoids in methanol/water（6：4） extract of P.kaempferi by LC-MS in positive ionization mode.A total of 9 diterpenoids were identified or tentatively characterized,and one of them is reported here for the first time.The described method could be utilized for the sensitive and rapid qualitative analysis of P.kaempferi.
出处
《药学学报》
CAS
CSCD
北大核心
2011年第2期213-220,共8页
Acta Pharmaceutica Sinica
基金
supported by the National High Technology Research and Development Program of China(Grant No.2003AA2Z2030)
program for Changjiang Scholar and Innovative Team in University(Grant No.985-2-063-112)
关键词
土荆皮
二萜
质量控制
定性分析
高效液相色谱-多级质谱
裂解
Pseudolarix kaempferi
diterpenoid
quality control
qualitative analysis
HPLC-ESI/MSn
fragmentation
