Description
Tetrahydropalmatine can be prepared from the total bases of tetrahydroxy berberine. Tetrahydropalmatine can be used to prepare palmatine. Palmatine has a broad-spectrum antibacterial effect, especially against Candida albicans. It can be used clinically to treat gynecological inflammation, bacillary dysentery, enteritis, respiratory and urinary tract infections, surgical infections, and conjunctivitis. Palmatine can also enhance the relaxation of the body's norepinephrine smooth muscle.
Tetrahydropalmatine, an active component isolated from corydalis, acts through inhibition of amygdaloid release of dopamine to inhibit an epileptic attack in rats.
Appearance
White to Orange to Green powder to crystal
Uses
DL-Tetrahydropalmatine is the main active substance of the Chinese herb corydalis which induces hypotension and bradycardia in rats through the antagonism of striatal dopamine D2 receptor.
In vivo research
Tetrahydropalmatine (THP), an active component isolated from corydalis (a Chinese herbal medicine), possesses analgesic effects. Picrotoxin treatment alone has a significant effect on the following activity measure: there is an increase in horizontal motion time (HMT), vertical motion time (VMT), clockwise turnings (CT), anticlockwise turning (ACT) and a decrease in freezing time (FT). Tetrahydropalmatine treatment alone causes a decrease in HMT, VMT and total distance traveled (TDT), but an increase in FT. Pretreatment of rats with an i.p. dose of 10 mg/kg or 15 mg/kg of Tetrahydropalmatine significantly attenuates the Picrotoxin-induced enhancement in HMT, VMT, CT, ACT and TDT, as well as reduction in FT. Another 48 rats under urethane anesthesia are randomly divided into six groups, each of eight rats. The s.c. injection of Picrotoxin causes an increase in amygdaloid release of dopamine (DA), while i.p. injection of Tetrahydropalmatine at 10 mg/kg has an insignificant effect on amygdaloid release of DA. Again, the Picrotoxin-induced increase in amygdaloid release of DA is significantly attenuated by pretreatment with Tetrahydropalmatine. The Picrotoxin-induced augmented amygdaloid release of DA is almost completely abolished by pretreatment with Tetrahydropalmatine 30 min before s.c. injection of Picrotoxin.
Preparation
A. Berberine hydrochloride is ring-opened under the conditions of p-toluenesulfonic acid, xylene, and HCl at 70°C to obtain desmethylene berberine hydrochloride.
B. Demethylene berberine hydrochloride is methyl etherified with potassium carbonate, methanol, and dimethyl sulfate at 40°C to obtain palmatine hydrochloride.
C. Palmatine hydrochloride is racemized under the conditions of methanol and sodium borohydride to obtain tetrahydropalmatine.
Uses
analgesic, hypnotic, papaverine-like
Uses
DL-Tetrahydropalmatine is the main active substance of the Chinese herb corydalis which induces hypotension and bradycardia in rats through the antagonism of striatal dopamine D2 receptor.
Definition
ChEBI: 2,3,9,10-tetramethoxy-6,8,13,13a-tetrahydro-5H-isoquinolino[2,1-b]isoquinoline is an alkaloid.
