Chemistry Reference
In-Depth Information
O
H
3
C
CH
3
H
3
C
HO
OH
CH
3
OH
CH
3
N
H
3
C
HO
H
3
C
H
5
C
2
O
O
CH
3
O
O
O
OCH
3
CH
3
CH
3
OH
O
CH
3
FIGURE 9.16
Structure of erthromycin.
9.13 ANTIBIOTIC MACROLIDES: ERYTHROMYCIN
Erythromycin (Figure 9.16) is a macrolide antibiotic that has an antimicrobial spec-
trum similar to or slightly wider than that of penicillin, and is often prescribed for
people who have an allergy to penicillins. For respiratory tract infections, it has bet-
ter coverage of atypical organisms, including
Mycoplasma
and legionellosis.
This macrocyclic compound contains a 14-membered lactone ring with ten asym-
metric centers and two sugars (L-cladinose and D-desosamine), making it a com-
pound that is difficult to produce via synthetic methods. Erythromycin is produced
in fermentation from a strain of the actinomycete
Saccharopolyspora erythraea.
9.14 ANTIPARASITIC DRUGS: AVERMECTINS
The avermectins (Figure 9.17) form a series of 16-membered macrocyclic lactone
derivatives with potent anthelmintic and insecticidal properties. These naturally
R
H
O
HO
O
O
O
O
O
O
O
H
O
O
OH
Avermectin B
1a
R = CH
2
CH
3
Avermectin B
1b
R = CH
3
O
H
OH
FIGURE 9.17
The avermectin family of compounds.
Search WWH ::
Custom Search