TACRINE HYDROCHLORIDE Property

Melting point:

280-284 °C(lit.)

storage temp. 

Inert atmosphere,2-8°C

solubility 

Soluble in aqueous buffers

pka

pKa 9.8 (Uncertain)

form 

Crystalline solid

color 

White to light yellow

CAS DataBase Reference

1684-40-8(CAS DataBase Reference)

EPA Substance Registry System

Tacrine hydrochloride (1684-40-8)

Safety

Hazard Codes 

T,Xn

Risk Statements 

25-36/37/38-20/22

Safety Statements 

26-36-45

RIDADR 

UN 2811 6.1/PG 3

WGK Germany 

3

RTECS 

AR9532500

HazardClass 

6.1(a)

PackingGroup 

II

Toxicity

LD50 intravenous in mouse: 5600ug/kg

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H301Toxic if swalloed

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

H331Toxic if inhaled

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

TACRINE HYDROCHLORIDE Chemical Properties,Usage,Production

Description

Tacrine is the first therapeutic launched specifically for the treatment of Alzheimer's disease which affects four million people in the US alone. Clinically significant improvement in cognition has been demonstrated in the patients with Alzheimer's disease. Although the cause of Alzheimer's disease is not understood, degeneration of cholinergic neurons is thought to be a primary factor in the development and progression of the disease. Tacrine is a reversible acetylcholinesterase inhibitor that presumably acts centrally by elevating the acetylcholine level in the cerebral cortex and by slowing degradation of acetylcholine from intact cholinergic neurons. While tacrine improves the symptoms of Alzheimer's disease, the underlining cause of the dementing process is not altered. It has also been suggested that the beneficial effects of tacrine may be due to its multiple effects on several neurotransmitter systems.

Description

Tacrine is a derivative of aminoacridine that functions as an inhibitor of both acetylcholinesterase (AChE) and butyrylcholinesterase (IC₅₀s = 31 and 26.5 nM, respectively). Tacrine also inhibits the uptake of serotonin and norepinephrine in rat cerebral cortex and decreases depolarization-induced calcium influx through L-type calcium channels in SN56 neuronal cells. Formulations containing tacrine have been used clinically in the treatment of Alzheimer’s disease.

Chemical Properties

Pale Yellow Solid

Originator

NIH (U.S.A.)

Uses

A potent centrally acting anticholinesterase, for therapy of memory deficits in patients with Alzheimers disease. THA also selectively blocks potassium channels in the central nervous system, which results in an increased release of acetylcholi

Uses

A potent centrally acting anticholinesterase for therapy of memory deficits in patients with Alzheimer's disease. THA also selectively blocks potassium channels in the central nervous system, which results in an increased release of acetylcholine and a prolongation of the action potential of the presynaptic cholinergic neurons.

Uses

anticholinesterase, cognitive adjuvant, K channel blocker

brand name

Cognex (Sciele).

General Description

Tacrine hydrochloride,1,2,3,4-tetrahydro-9-aminoacridine hydrochloride (THA,Cognex), is a reversible cholinesterase inhibitor that hasbeen used in the treatment of Alzheimer disease for severalyears. The drug has been used to increase the levels of AChin these patients on the basis of observations from autopsiesthat concentrations of ChAT and AChE are markedly reducedin the brain, whereas the number of muscarinic receptorsis almost normal. The use of the drug is not withoutcontroversy, as conflicting results on efficacy have been reported.The drug has been used in mild-to-moderateAlzheimer dementia.

General Description

Yellow needles (from concentrated hydrochloric acid); white powder. pH of 1.5% solution: 4.5-6. Bitter taste.

Air & Water Reactions

Water soluble.

Reactivity Profile

TACRINE HYDROCHLORIDE is incompatible with strong oxidizing agents, acid chlorides and acid anhydrides . Neutralize bases in slightly exothermic reactions.

Fire Hazard

Flash point data for TACRINE HYDROCHLORIDE are not available; however, TACRINE HYDROCHLORIDE is probably combustible.

Biological Activity

Potent cholinesterase inhibitor, a cognition enhancer in vivo .

Metabolism

Tacrine is extensively metabolized by CYP450 to at least three metabolites. The major metabolite, 1-hydroxy-tacrine, is active. Its elimination half-life is between 1.5 and 4 hours, with metabolites being are excreted via the urine.