DƯỢC LÍ Goodman & Gilman's The Pharmacological Basis of Therapeutics 12th, 2010

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H 3 CO O CH 3
C N
O
O
C O H 2 N
C OC 2 H 5
H 2 N
2
1
O
C
C 2 H 5
OCH 2 CH 2 N
COCAINE
BENZOCAINE
PROCAINE
C 2 H 5
SECTION II
NEUROPHARMACOLOGY
O
C 2 H 5 H 9 C 4
O
CH 3
H 7 C 3 O
C OCH 2 CH 2 N
N
C OCH 2 CH 2 N
C 2 H 5 H
CH 3
H 2 N
PROPARACAINE
TETRACAINE
C 4 H 9
CH 3
CH 3 CH CH
O
O 3
3
C O
2 H 5
N
NH C CH NH
CH
C
NH C 2 N
3 H 7 NH C
C S
CH 2 H 5
3
CH
C OCH
3
LIDOCAINE
O ARTICAINE
BUPIVACAINE
CH 3
CH 3 CH 3
CH O
3 O
O
N
NH C CH NH C 3 H 7
NH C
NH C
CH
N
3
CH3
CH 3 H 7 C 3
PRILOCAINE
ROPIVACAINE
MEPIVACAINE
C 9 H 4 O
O
C O
2 H 5
N C NH CH 2 CH 2 N
H 9 C 4 O
C CH 2 CH 2 N
C 2 H 5
DIBUCAINE
DYCLONINE
H 9 C 4 O
OCH 2 CH 2 CH 2 N O
PRAMOXINE
Figure 20–1. Structural formulas of selected local anesthetics. Most local anesthetics consist of a hydrophobic (aromatic) moiety
(black), a linker region (orange), and a substituted amine (hydrophilic region, in red). The structures above are grouped by the nature
of the linker region. Procaine is a prototypic ester-type local anesthetic; esters generally are well hydrolyzed by plasma esterases, contributing
to the relatively short duration of action of drugs in this group. Lidocaine is a prototypic amide-type local anesthetic; these
structures generally are more resistant to clearance and have longer durations of action. There are exceptions, including benzocaine
(poorly water soluble; used only topically) and the structures with a ketone, an amidine, and an ether linkage. Chloroprocaine has a
chlorine atom on C2 of the aromatic ring of procaine.
conduction slows, and the safety factor for conduction
decreases. These factors decrease the probability of
propagation of the action potential, and nerve conduction
eventually fails.
Local anesthetics can bind to other membrane
proteins (Butterworth and Strichartz, 1990). In particular,
they can block K + channels (Strichartz and Ritchie,
1987). However, since the interaction of local anesthetics