An Improved Preparation of D-Glyceraldehyde 3-Phosphate and Its Use in the Synthesis of 1-Deoxy-D-xylulose 5-Phosphate

D-Glyceraldehyde 3-phosphate (=D-GAP: 2) was prepared by all improved chemical method (Scheme 2), and it was then employed to synthesize 1-deoxy-D-xylulose 5-phosphate (-DXP: 3) which is enzymatically one of the key intermediates in the MEP (4) terpenoid biosynthetic pathway (Scheme 1). The recombinant DXP synthase of Rhodobacter capsulatus was used to catalyze the condensation of D-glyceraldehyde 3-phosphate (2) and pyruvate (=2-oxopropanoate: 1) to produce the sugar phosphate 3 (Scheme 2). The simple two-step chemoenzymatic route described affords DXP (3) with more than 70% overall yield and higher than 95% purity. The procedure may also be used for the synthesis of isotope-labeled DXP (3) by using isotope-labeled pyruvate.