D-Glyceraldehyde derived allylic

The biologically important 2-deoxypentoses can be prepared readily by the two-carbon chain elongation of 2,3- -isopropylidene-D-glyceraldehyde following Roush s allylation method (Scheme 13.54), relying on the highly diastereoselective additions of enantiomerically pure allylboronates derived from (R,R) and (5, 5 )-tartaric acid [100]. Similarly, the 2,6-dideoxyhexose derivative 155 was obtained by Roush and Straub (Scheme 13.54) [101]. 

Ortho ester Claisen rearrangements as well as the Ireland Claisen variation of (1,3-diox-olan-4-yl)allyl alcohol derivatives 1, prepared from readily available 1,2-O-isopropylidene-D-glyceraldehyde, do not exhibit significant stereoselectivity590-591. 

D-Glyceraldehyde acetonide (118) has also been used for the synthesis of other (3-lactams (Scheme 14). It was converted into the Schiff base 129, followed by reaction with potassium azidoacetate, cyanuric chloride and triethylamine to give the p-lactam 130 as a single c/s-isomer in 55% yield. The reaction of 130 with methoxyacetyl chloride in the presence of triethylamine afforded the cw-p-lactam 131. Similarly, c/ -p-lactams 131-135 were also prepared as single isomers in comparable yields. Acid hydrolysis of 130 afforded 136, which underwent oxidation of the diol side chain and then removal of the p-methoxybenzyl group with CAN to afford 137. The allyl derivative 135 was oxidized to... 

Several amino-sugar syntheses have employed 3- and 4-carbon chiral starting materials. 2,3- -Isopropylldene-D-glyceraldehyde (34) has been elaborated into the 3-acetamido-2,3-dldeoxy-pyrano-side (35) and the 3-nitro-furanoslduronlc acid (36) by stereoselective allylation of the nitronate dlanlon derived from nltro derivative (37) (Scheme 11) and into 2-amlno-2-deoxy-D-arabinose... 

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