Page 74 - Org 3 theoritical book 2024-25

Clinical Pharmacy PharmD - 2024/2025 Level 2 Pharmaceutical Organic Chemistry-3 (PC 305)
A monosaccharide containing an aldehyde group is called an aldose;

One containing a ketone group is called a ketose.

These two classifications are frequently combined.

A C 4 aldose, for example, is called an aldotetrose; a C 5 ketose is called a ketopentose.

➢ D and L Designations of Monosaccharides

The simplest monosaccharide which has chiral center is glyceraldehyde.

It exists in two enantiomeric forms that have the absolute configurations shown here:

(+)-glyceraldehyde is designated (R)(+)-glyceraldehyde and (-)-glyceraldehyde is

designated (S)(-)-glyceraldehyde.

The D–L system of stereochemical designations has the disadvantage of specifying the

configuration of only one chiral center that of the highest numbered chirality center.