Tetraric acids

For the tetraric acids, the trivial name tartaric acid remains in use, with the stereochemistry given using the R,S system. Esters are referred to as tartrates (the second a is elided). 

Tetraric acids, trivial names, 111 Thiamine, 267-307 biosynthesis from 5-amino- l-(/3-D-... 

Resolution of the dl acid (lab) was attempted with brucine, cinchonine, quinine, and strychnine, and it was found that brucine gave superior results in comparison with the other alkaloid bases tried. In this way, the most insoluble brucine salt in the resolution experiments was found to yield, on liberation of the free acid from the salt, a pure levorotatory isomer (la). Oxidation of this isomer with nitric acid gave levorotatory 2-A.Qox.y-r>-glyc-ero-tetraric acid [(— )-L-malic acid XIV] identical with the natural form. From the mother liquor of the resolution with brucine, the other isomer as the free acid (dextrorotatory Ib) was obtained. This isomer, however, was not converted with nitric acid into 2-deax.y-ij-glycero- j iTax. Q, acid [(+)-d-malic acid XV]. 

Deoxy-D-gij/cero-tetraric acid [(—)-L-Malic acid natural form]... 

Deoxy-h-glycero-tetraric acid [(+)-D-Malic acid]... 

Dihydroxybutanoic acid, a 3-deoxytetronic acid, is the only theoretically possible four-carbon metasaccharinic acid it was isolated by Nef in the dl form (Ilab) in the course of his work on the action of sodium hydroxide on D-arabinose. It therefore constitutes the only four-carbon saccharinic acid isolated to date from a sugar-alkali reaction. Resolution of this on acid (Ilab) was accomplished by Nef, who showed that the dextrorotatory acid (Ila) upon oxidation gave rise to 2-deoxy-L-f/Z2/cero-tetraric acid [(-)-)-d-malic acid XV]. During the course of this work, several derivatives of the L and DL saccharinic acids (lib and Ilab) were prepared, but only the brucine salt of the d acid (Ila) was reported. 

The racemic 3-deoxytetronic acid (Ilab) thus produced was resolved with brucine, the more insoluble brucine salt yielding, on liberation by means of barium hydroxide, a dextrorotatory acid (Ha) which gave, on oxidation with nitric acid, a product identical with 2-deoxy-L-gd2/cero-tetraric acid [(-b)-D-malic acid XV]. Similarly, the levorotatory acid (Ilb), obtained from the mother liquor of the resolution with brucine, was oxidized with nitric acid to 2-deoxy-D-5lycero-tetraric acid [(—)-L-malic acid XIV]. The... 

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