Modified L-threose and D-erythrose as substrates of transketolase and fructose-1,6-bisphosphate aldolase.: Application to the synthesis of new heptulose analogues

Nine substituted butanals lacking alpha-hydroxyl group were tested as substrates for transketolase and fructose-1,6-bisphosphate aldolase in order to demonstrate the usefulness of these enzymes for the synthesis of 4-deoxy-D-fructose and 4-deoxy-L-sorbose derivatives as well as 5-deoxy-heptuloses of D and L configurations. All compounds lead to the corresponding ketoses by aldolase catalysis, but only a 4-phosphorylated one has a sufficient reactivity to ensure a transketolase catalysed synthesis. (C) 1998 Elsevier Science B.V. All rights reserved.