I2-Catalyzed Oxidative Condensation of Aldoses with Diamines: Synthesis of Aldo-Naphthimidazoles for Carbohydrate Analysis

Molecules

Chunchi Lin¹  Wei-Ting Hung¹  Chien-Yuan Kuo¹  Kuo-Shiang Liao¹  Yin-Chen Liu¹ 

[1] Genomics Research Center, Academia Sinica, No. 128, Academia Road Section 2, Nankang, Taipei 11529, Taiwan

关键词: iodine;    saccharides;    aldo-imidazole (aldo-IM);    matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI–TOF MS);   

DOI  :  10.3390/molecules15031340

来源: mdpi

【 摘 要 】

A novel method for the conversion of unprotected and unmodified aldoses to aldo-imidazoles has been developed. Using iodine as a catalyst in acetic acid solution, a series of mono- and oligosaccharides, including those containing carboxyl and acetamido groups, undergo an oxidative condensation reaction with aromatic vicinal diamines at room temperature to give the corresponding aldo-imidazole products in high yields. No cleavage of the glycosidic bond occurs under the mild reaction conditions. The compositional analysis of saccharides is commonly realized by capillary electropheresis of the corresponding aldo-imidazole derivatives, which are easily synthesized by the reported iodine-promoted oxidative condensation. In addition, a series of aldo-imidazoles were determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI–TOF MS) to analyze molecular weight and ion intensity. The diamine-labeled saccharides showed enhanced signals in MALDI–TOF MS. The combined use of aldoimidazole derivatization and mass spectrometric analysis thus provides a rapid method for identification of saccharides, even when less than 1 pmol of saccharide is present in the sample. These results can be further applied to facilitate the isolation and analysis of novel saccharides.

【 授权许可】

CC BY   
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.