5-Hydroxymethyl-2-furfural, a clinical trials agent for sickle cell anemia, and its mono/di-glucosides from classically processed steamed Rehmanniae Radix.

Rehmanniae Radix (Di Huang) is one of the most important traditional Chinese medicines (TCM), and is used for multiple therapeutic purposes. In our investigation of the chemical constituents of Rehmanniae Radix, steamed roots were prepared by the classical processing method. Reversed-phase HPLC of the 50% MeOH extract of steamed Rehmanniae Radix yielded three 5-hydroxymethylfurfural derivatives.