3,5-Dihydroxycarboxylic acid

Dihydroxyacid dehydratase (Val, lie biosynthesis) 2,3-dihydroxycarboxylic acid/ 2-keto carboxylic acid... 

This mechanism divides into two sequences of steps. In the first part of the mechanism, an acetal is hydrolyzed to acetone and a dihydroxycarboxylic acid. 

In the second set of steps, the dihydroxycarboxylic acid forms a cyclic ester (a lactone). 

A prior derivatization of glycolic acid into chiral 5,6-diphenyl-l,4-dioxan-2-one paves the way to anfi-2,3-dihydroxycarboxylic acids by an aldol-type process. ... 

In some reaction schemes for the identification of tartrate and for the general determination of aliphatic a, 3-dihydroxycarboxylic acid, the same chemistry is applied but without the addition of brome. The result of this reaction is (Figure 3.33.7), which is stated to give a purple-red to orange-red color. ... 

Soon thereafter, Merck developed a synthesis for simvastatin (Zocor), which came on the market in the late 1980s and is still used worldwide for the control of plasma cholesterol levels. These drugs and several synthetic modifications now available inhibit HMG-CoA reductase by forming an enzyme-inhibitor complex that prevents further catalytic action of the enzyme. It is reasoned that the 3,5-dihydroxycarboxylic acid part of each drug binds tightly to the enzyme because it mimics the hemithioacetal intermediate formed by the first reduction of HMG-CoA. 

Dihydro-2-pyrones and 4-hydroxytetrahydro-2-pyrones from, d-dihydroxycarboxylic acid tert- mty esters... 

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