
TY  - JOUR
A1  - Limberg, G 
A1  - Limberg, G 
A1  - Thiem, J 
A1  - Thiem, J 
T1  - Synthesis of Modified Aldonic Acids and Studies of Their Substrate Efficiency for Dihydroxy Acid Dehydratase (DHAD)
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1996
VL  - 49
IS  - 3
SP  - 349
EP  - 356
KW  - 
UR  - https://doi.org/10.1071/CH9960349 
N2  - Modified aldopentonic and aldohexonic acids were synthesized in order to study the electronic requirements for a successful enzymatic conversion into their corresponding 2-keto 3-deoxy analogues by dihydroxy acid dehydratase (DHAD), an enzyme from the biosynthetic pathway of branched chain amino acids. Analytical tests with the novel artificial substrates (18)-(21) and (27) provided evidence that the amount of conversion could be enhanced by replacement of the hydroxy group at C4 of L-arabinonic acid (21) with less electron-withdrawing, ambivalent or electron-donating substituents. Modified aldohexonic acids were no substrates for DHAD, perhaps due to less perfect binding to the active site presumably for steric reasons. For 4-deoxy-L-threo-pentonic acid (18) the enzymatic conversion into 3,4-dideoxy-2-ketopentonic acid (29) by DHAD could be achieved on a preparative scale. 
ER  -

