Dolbier HW Solutions 619

Dolbier HW Solutions 619 - 713 CARBOHYDRATES (b) All the...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
( b ) All the aldonic acids and their lactones obtained on oxidation of the aldohexoses are optically active. The presence of a carboxyl group at one end of the carbon chain and a CH 2 OH at the other precludes the existence of meso forms. ( c ) Nitric acid oxidation of aldoses converts them to aldaric acids. The same D -aldoses found to yield optically inactive alditols in part ( a ) yield optically inactive aldaric acids. ( d ) Aldoses that differ in con f guration only at C-2 enolize to the same enediol. The stereogenic center at C-2 in the D -aldose becomes sp 2 -hybridized in the enediol. The other pairs of D -aldohexoses that form the same enediols are D -Glucose and D -mannose D -Gulose and D -idose D -Galactose and D -talose 25.20 ( a ) To unravel a pyranose form, locate the anomeric carbon and mentally convert the hemiacetal
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/03/2011 for the course CHM 2210 taught by Professor Reynolds during the Fall '01 term at University of Florida.

Ask a homework question - tutors are online