Many modular glucosides discovered in the metabolome of the model organism C. elegans contain a phosphate group at the 3-position of the glucose. Recent work has provided insights into how other moieties are attached to the sugar, but the point in their syntheses at which the phosphate is attached remains unknown. In this study, glucose 3-phosphate was synthesized and compared with other glucose phosphates and C. elegans samples via HPLC-HRMS. Glucose 3-phosphate was verified to be present in the C. elegans metabolome along with canonical glucose 6-phosphate and 1-phosphate, but not glucose 2-phosphate. The presence of glucose 3-phosphate suggests that the phosphate may be attached first in the biosynthesis of 3-phosphorylated glucoside derivatives.