D,L-Glyceraldehyde

An enzymatic aldol condensation of dihydroxyacetone phosphate and D,L-glyceraldehyde has reportedly48 given a mixture of L-sorbose l-phos-phate along with D-fructose 1-phosphate. The ketoses may be set free with phosphatase. 

The diacetone compound was shown to be l,2 5,6-diisopropylidene-D-sorbitol by the fact that it consumed one mole of periodate with the concomitant formation of isopropylidene-D,L-glyceraldehyde, but not of formaldehyde (see page 147).148... 

Vandelli, M.A. Rivasi, P. Guerra, P. Forni, F. Arletti, R. Gelatin microspheres crosslinked with D, L-glyceraldehyde as a potential drug delivery system preparation, characterisation, in vitro and in vivo studies. Int. J. Pharm. 2001,215, 175-184. 

Cyanohydrin formers Pyruvates a-Ketoglutarates D,L-Glyceraldehyde Glucose Mercaptopyruvates... 

In the present work an attempt has been made to find out the difference between the pathways of carbon conversion in the chain of the above mentioned reactions by means of D,L-glyceraldehyde(GA), recommended by Stocks and Walker (18, 19) as a specific inhibitor of dark reactions of photosynthesis, particularly in BC reaction cycle. The authors have shown... 

Fig. 1. Hipothesis of two interacting carboxylation systems in isoprens releasing plant photosynthesis. Designations BC - pool of reactions of Benson-Calvin cycle AcCoA - pool of acetyl-CoA and isoprene biosynthesis RUBPC/O-ribulosebisphsphate C/0 X-C-unknown carboxylase leading to acetyl-CoA biosyynthesis PGA-phosphoglyceric acid PGAL- phosphoglyceric aldehyde GA-D,L-glyceraldehyde a,b,c...n-alternative pathways of acetyl-CoA use.

Cyclopentane rings can also be formed readily by treating 6-deoxy-6-nitro-D-fructose (prepared enzymatically from dihydroacetone phosphate and 3-deoxy-3-nitro-D,L-glyceraldehyde in the presence of an aldolase then phosphatase) with acetic anhydride and boron trifluoride etherate, then subjecting the mixture to chromatography on silica gel thereby affording 63 and the epimer at the indicated carbon atom. ... 

Most natural carbohydrates belong to the d family that is, the stereocenter farthest from the carbonyl group has the same configuration as that in (R)-(-H)-2,3-dihydroxypropanal [D-(-l-)-glyceraldehyde]. 

Most natural sugars have a stereocenter that is identical to that in (/J)-2,3-dihydroxypropanal, shown as a Fischer projection below. What is the (very popular) common name for this compound (a) D-(+)-Glyceraldehyde (b) d-( )-glyceraldehyde (c) L-( + )-glyceraldehyde (d) l-( —)-glyceraldehyde... 

Ketoses have been prepared using transketolase catalysis. The enzyme, isolated from Saccharomyces cerevisiae (baxer s yeast) or from spinacb leaf was investigated for substrate specificity and it ivas shown that it was not necessary for the ketose to be phosphory-lated. The general biosynthetic condensation shown in Scheme 5 was used in the preparation of L-erythrulose from glycolaldehyde, D-xylulose from D- or D,L-glyceraldehyde, and 3-deoxy-U-xylulose from... 

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