D-Allaric acid

D-Allaric acid has a symmetry plane and is a meso compound, but o-glucaric acid is chiral. 

Thuringiensin 2-<9-[4-0-(S -deoxyadenosin-S -yl)-)S-D-glucopyranosyl]-D-allaric acid 4-phosphate). 

D-allaric acid (optically inactive) D-altraric acid (optically active)... 

To the names of aldaric acids that are symmetrical, which therefore have no D- or L- prefix, the prefix meso- may be added for the sake of clarity. Examples mero-erythraric acid, meso-ribaric acid, meso-xylaric acid, meso-allaric acid, meso-galactaric acid. 

Allaric acid D-form 1,4-Lactone, 3-benzyl, 5-benzoyl, 6-Me ester, A-74... 

This operation may cause important changes in the synunetry of the molecule. Thus, D-allaric add has a mirror plane. It is therefore a meso compound and not optically active. (This also means that D-allaric add is identical with L-aBaric add.) On the other hand, D-glucaric acid is still optically active. 

Hexaric acids allaric (meso), formerly a//o-mucic galactaric (meso), formerly mucic D- and L-glucaric (l- and D-gularic), formerly D- and L-g/Mco-saccharic D- and L-mannaric, formerly D- and L-manno-saccharic D- and L-idaric, formerly D- and L-ido-saccharic and D- and L-altraric (d- and L-talaric), formerly D- and L-ta/o-mucic acid. 

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