Chemistry Reference
In-Depth Information
Resins from
Pinaceae
have been used for centuries in the treatment of infected wounds,
boils and pyoderma. The biological activities of C-13 deisopropylated and/or C-7
oxidised resin acid derivatives (
58
-
63
) (
Scheme 6.13
) were tested against various
microorganisms to determine the structural features responsible for biological activity
and to determine the influence of the C-13 isopropyl group on antimicrobial activity
[33]. The results indicate that compounds (
62
) and (
63
), either singly or together,
inhibited the growth of Gram-positive bacteria but they inhibited the growth of
Gram-negative bacteria only when they were used together. Compounds (
58
) and
(
60
) showed no activity. Compound (
59
) showed weak activity against Gram-positive
bacteria only. Methyl
cis
and
trans
7-oxo-13-deisopropyldehydroabietate and a
mixture of both isomers exhibited activity against fungi and bacteria.
Scheme 6.13
Structure of resin acid derivatives (
58
-
63
)
Quaternary ammonium salts are frequently used as antibacterial agents because
they can disrupt cell membranes through the binding of their ammonium cationic
to anionic sites in the outer tissue layer of bacteria. Combined with a tricyclic
hydrophenanthrene structure, rosin-based quaternary ammonium salts exhibited
good antibacterial activity [34-37]. Compared with abietic acid, dehydroabietic acid
and dehydroabietylamine were much more resistant to oxidation in air, and have
been widely used as starting materials for the design and synthesis of rosin-based
quaternary ammonium compounds. The antibacterial activities of these quaternary
ammonium compounds are discussed in
Chapter 5
.
6.2.4 Effects on the Digestive System
Ulcers are sore, or raw, areas that form in the lining of the stomach or the duodenum.
For a long time, physicians thought that stress and certain foods caused ulcers. Now
they know that most ulcers are caused either by infection with a bacterium called
Helicobacter pylori
or by the long-term use of aspirin or other nonsteroidal anti-
inflammatory drugs. Antiulcer drugs are used as part of the treatment for ulcers. The
three basic types of antiulcer drugs are histamine H2 receptor blockers, acid pump
inhibitors, and mucosal protective medications [38].
