IFENPRODIL HEMITARTRATE

Chemical Properties

Crystalline Solid

Originator

Vadilex,Carriere,France,1972

Uses

Vasodilator (cerebral and peripheral)

Uses

Vasodilatator;Adrenergic antagonist

Uses

Ifenprodil (+)-tartrate salt has been used:

• to test the action in a KCl-induced cortical spreading depression (CSD) animal
• to study its effects on electrophysiological properties and spontaneous spikes in neocortical pyramidal cells
• to investigate its therapeutic effects

Definition

ChEBI: Ifenprodil tartrate is a member of piperidines.

Manufacturing Process

The initial steps involve reacting benzyl chloride with 4- hydroxypropiophenone. The benzyloxypropiophene thus obtained is first brominated and then reacted with 4-benzylpiperidine to give 1-(pbenzyloxyphenyl)-2-(4-benzyl-piperidino)propan-1-one.
The neutral tartrate may be prepared directly by reduction of 1-(pbenzyloxyphenyl)-2-(4-benzyl-piperidino)propan-1-one. For the reduction, a mixture of 175 g of ketone (0.425 mol) and 32 g of tartaric acid (0.213 mol) is hydrogenated at 50°C under pressure of 50 kg/cm2 in 440 ml of methanol in the presence of 12 g of palladium on charcoal.
The catalyst is filtered off at elevated temperature, and the filtrate is concentrated by evaporation under reduced pressure to a volume of 300 ml and added in a thin stream to 2.5 liters of diethyl ether with mechanical agitation. The precipitate is separated, washed with diethyl ether and dried in vacuo at 80° to 85°C for several hours. 325 g (96% yield) of the neutral tartrate of 1-(p-hydroxyphenyl)-2-(4-benzyl-piperidino)propan-1-ol are obtained.

Therapeutic Function

Vasodilator

General Description

Ifenprodil is a phenylethanolamine, which stimulates blood circulation. It has anticonvulsant and antinociceptive properties. Ifenprodil is used to treat posttraumatic stress disorder, cerebrovascular diseases and peripheral arterial obliterative disease. It blocks G protein-coupled inwardly-rectifying potassium channels (GIRKs) and interacts with α1 adrenergic, N-methyl-D-aspartate and serotonin receptors.

Biological Activity

Ifenprodil hemitartrate is a NMDA receptor antagonist, acting at the polyamine site. Also an α-adrenergic vasodilator. σ2 ligand displaying about 3-fold selectivity over σ1 sites.

Biochem/physiol Actions

NMDA antagonist acting at the polyamine site; neuroprotective agent; α-adrenergic central and peripheral vasodilator; α2 adrenergic receptor ligand.

in vitro

Ifenprodil treatment of oocytes, at NR1A/NR2B and NR1A/NR2A receptors, inhibited NMDA-induced currents with IC50 of 0.34 μM and 146 μM, respectively, and voltage-clamped at -70 mV. Ifenprodil acts as a weak open channel blocker of NR1A/NR2A receptors, the degree of inhibition of NR1A/NR2A receptors by 100 μM fenprodil is not affected by extracellular glycine concentration. Increasing glycine concentration decreased the inhibitory effect of 1mMIfenprodil on NR1A/NR2B receptors. Ifenprodil (10 μM) acts on young rat cortical neurons, a single population of receptors with high affinity for glycine, inhibits almost all NMDA receptor-evoked currents. Ifenprodil (10 μM) inhibited a significant proportion of high- and low-affinity components in aged rat cortical neurons, revealing three pharmacologically distinct distribution populations of NMDA receptors in a single neuron. Ifenprodil antagonizes NMDA receptors in an activity-dependent manner and also enhances the receptor's affinity for glutamate recognition site agonists. In the inhibition curves of Ifenprodil on 10μM and 100μM NMDA-evoked currents, IC50 was 0.88μM and 0.17μM, respectively. Ifenprodil (3μM) can enhance the control level of cultured rat cortical neurons. Enhanced by about 200%. Ifenprodil has a 39- and 50-fold enhanced affinity for NMDA receptors in the agonist-bound activated and desensitized states compared to the resting, agonist-unbound state. Ifenprodil binds to NMDA receptors with a 6-fold increased affinity for glutamate receptor agonists.

storage

Room temperature