Fundamentals of Medicinal Chemistry

Table 1.8 (continued)

Subclassification Structure

Sulphatides (acidic glycolipids) have

galactose residue with a sulphate

group.

CHOH

H

O

CH 2 OH

O

CH 2 OH

NH

COCH 3

H

H

NHCOCH 3

CHOH

OH

O

CHCHCHNHCOR

OH

O

HOCH 2

H

H

H

H

CH 2

CH 3 (CH 2 ) 12 CH

OH

H

O

H

H

H OH

O

H

H

O

OH

O

HOCH 2

H

H

H OH

O H COOH

CH 3 (CH 2 ) 12 CH CHCHCHNHCOR

H

HO O O

HOCH 2

H

H

H OH

CH 2

OH

Aβ-D-galactose residue OSO− 3

A D-N-acetylgalactosamine residue

A D-N-acetylneuraminic acid residue (sialic acid)

Polysaccharide

chain

Z

Z

Gangliosides (acidic glycolipids) have

a polysaccharide chain which

branches through an ether linkage at

the point marked Z. A typical branch

residue would be sialic acid, shown

bottom right.

1.6 Nucleic acids

1.6.1 Introduction

The nucleic acids are the compounds that are responsible for the storage and

transmission of the genetic information that controls the growth, function and

reproduction of all types of cell. They are classified into two general types: the

deoxyribonucleic acids (DNA), whose structures contains the sugar residue

b-D-deoxyribose, and theribonucleic acids (RNA), whose structures contain

the sugar residueb-D-ribose (Figure 1.16). Both types of nucleic acid consist

of long polymer chains (Figure 1.28(a) ) based on a repeating unit known as a

nucleotide(Figure 1.28(b) ). Each nucleotide consists of a purine or pyrimidine

(Figure 1.28(c) ) base bonded to the 1’carbon atom of a sugar residue by a

b-N-glycosidic link (Figure 1.28(d) ). These sugar–base units, which are known

26 BIOLOGICAL MOLECULES