Characterization and removal of a previously unknown impurity in the synthesis of 2-NBDG
Presentation Type
Poster
Department
Chemistry
Major
Sports Medicine
Abstract
2-NBDG is a fluorescently tagged glucose derivative that is used to track sugar uptake in living organisms. However, synthesizing 2-NBDG is both low yield (inefficient synthesis) and extremely time-consuming, contributing to its prohibitive costs. The goal of this project was to improve on existing methods of purifying 2-NBDG.
When we followed the published synthesis of 2-NBDG, we obtained 2-NBDG that was contaminated with an unknown impurity, as evidenced by its 1H-NMR spectra. This impurity was isolated and characterized as triethylammonium chloride. This impurity was not reported in the previous literature and its presence might have mistakenly inflated previously published yields by up to 26%.
Different methods of purification via normal phase column chromatography, reverse phase columns, ion-exchange columns, solubility in solvents, and different bases were used in an attempt to obtain a pure 2-NBDG product yield. Ultimately, the 2-NBDG was most effectively purified by using a cation exchange column with water as the mobile phase. By the conclusion of our project, we were able to produce highly pure 2-NBDG in 41% yield starting from NBD-F using NEt3/MeOH and purified by a normal phase column followed by a cation exchange column. Future work may focus on swapping out the normal phase chromatography step entirely.
Faculty Mentor
Timothy Dong, Ph.D.
Funding Source or Research Program
Summer Undergraduate Research Program, Undergraduate Research Fellowship
Characterization and removal of a previously unknown impurity in the synthesis of 2-NBDG
2-NBDG is a fluorescently tagged glucose derivative that is used to track sugar uptake in living organisms. However, synthesizing 2-NBDG is both low yield (inefficient synthesis) and extremely time-consuming, contributing to its prohibitive costs. The goal of this project was to improve on existing methods of purifying 2-NBDG.
When we followed the published synthesis of 2-NBDG, we obtained 2-NBDG that was contaminated with an unknown impurity, as evidenced by its 1H-NMR spectra. This impurity was isolated and characterized as triethylammonium chloride. This impurity was not reported in the previous literature and its presence might have mistakenly inflated previously published yields by up to 26%.
Different methods of purification via normal phase column chromatography, reverse phase columns, ion-exchange columns, solubility in solvents, and different bases were used in an attempt to obtain a pure 2-NBDG product yield. Ultimately, the 2-NBDG was most effectively purified by using a cation exchange column with water as the mobile phase. By the conclusion of our project, we were able to produce highly pure 2-NBDG in 41% yield starting from NBD-F using NEt3/MeOH and purified by a normal phase column followed by a cation exchange column. Future work may focus on swapping out the normal phase chromatography step entirely.