Xylulose

Xylulose is a ketopentose, a monosaccharide containing five carbon atoms, and including a ketone functional group. It has the chemical formula C5H10O5. In nature, it occurs in both the L - and D -enantiomers. 1-Deoxyxylulose is a precursor to terpenes via the DOXP pathway.

Pathology
L -Xylulose accumulates in the urine in patients with pentosuria, due to a deficiency in L-xylulose reductase. Since L -xylulose is a reducing sugar like D -glucose, pentosuria patients have been wrongly diagnosed in the past to be diabetic.