质谱学报2016，Vol.37Issue(6)：492-503,12.DOI:10.7538/zpxb.youxian.2016.0027
含 N-非取代葡糖胺残基肝素四糖的制备与表征
Preparation and Characterization of Heparin Tetrasaccharide with N-unsubstituted Glucosamine Residues
摘要
Abstract
The rare GlcNH 3 + residues implicated in important cellbiological and patho-physiological phenomena are also now particularly hot subjects in the pharmaceutical industry.Recently its tumour invasion and metastasis has raised interest.However,it is difficult to prepare naturally-occuring,because of their low abundance in GlcNH 3 +-containing oligosaccharides from HS.Therefore,the ability to chemically generate a series of structurally-defined oligosaccharides containing GlcNH 3 + residues would great-ly contribute to investigating their natural role in HS.In this study,heparin tetrasac-charides (dp4s)possessing one and two GlcNH +3 residues were prepared from partially de-N-sulfation of the fully sulfated dp4.Then the structure of dp4s was further detected by liquid chromatography-ion trap/time-of-flight mass spectrometry (LC/MS-IT-TOF). Two dp4s (dp4-1 and dp4-2 )are obtained,in which dp4-1 with one GlcNH +3 residue located in the central position,while dp4-2 with two GlcNH +3 residues located in the central and reducing terminal positions. <br> The results of extracted ion chromatogram (EIC)in LC/MS-IT-TOF system sug-gest that minor sulfate losses of the dp4s appear in MS ion source,but most of the sam-ples maintain the original structure,which is helpful for determining the accurate molec-ular weight of heparin/HS oligosaccharides with GlcNH 3 + residues. MS and MS2 analysis show different fragmentation patterns of dp4s with different GlcNH 3 + residues using the same MS parameters.0,2 X2 fragmentation near the non-reducing end of oligo-saccharide was only detected in dp4-1.Meanwhile,1 ,5 X2 ,2 ,4 A4 and 1 ,5 A4 fragmentations were only appeared in dp4-2.The dp4 with higher GlcNH +3 residues revealed more cross-ring cleavage patterns,suggesting that higher positive charges might make the ring more fragile,presumably reflecting the markedly different conformations and chem-ical environments at these positions,which results in different dissociation of dp4s in MS.This provides a foundation for further structural identification and quantification of GlcNH 3 +-oligosaccharides by mass spectrum analysis,which could lead to a greater understanding of the biological roles of GlcNH 3 + residues in HS/heparin.关键词
肝素/四糖/N-非取代葡糖胺二糖/液相色谱-离子阱-飞行时间质谱(LC/MS-IT-TOF)/裂解规律Key words
heparin/tetrasaccharide/N-unsubstituted disaccharide/liquid chromatog-raphy-ion trap/time-of-flight mass spectrometry (LC/MS-IT-TOF)/fragmentation pat-tern分类
化学化工引用本文复制引用
梁群焘,魏峥..含 N-非取代葡糖胺残基肝素四糖的制备与表征[J].质谱学报,2016,37(6):492-503,12.基金项目
国家自然科学基金(21343013)资助 （21343013）
