Physical and chemical properties
Appearance and properties: white crystalline solid
Density: 1.28 g/cm3
Melting point: 147-153ºC dec
Boiling point: 419.5ºC at 760 mmHg
Flash point: 207.5ºC
Stability: Stable at normal temperatures and pressures.
Storage conditions: Keep tightly closed.
Vinpocetine can be extracted from (+)-vincamine (Vincamine) extracted from Vinca minor, a plant of the Apocynaceae family, as a raw material, dehydrated to apovincamine (Apovincamine), and then hydrolyzed to obtain its acid Apovincaminic acid. Take the acid (1.0g, 0.003mol) and 0.17g potassium hydroxide and dissolve them in 80mL dry ethanol, add ethyl bromide (.4g, 0.0036mol), and reflux for 3h. After the reaction is completed, cool and evaporate to dryness. The residue is dissolved in 500mL 2% sulfuric acid and the pH value is adjusted to 8. Extract with dichloromethane, dry with potassium carbonate, evaporate most of the dichloromethane, and add ethanol. Place it at 0℃ overnight, filter and collect the precipitated crystals, wash with cold ethanol, and dry to obtain 0.66g of vinpocetine.
Pharmacological effects
Vinpocetine is a semi-synthetic vincamine derivative. Its effects are similar to those of vincamine, and it has a high selective dilation effect on cerebral blood vessels. The pharmacological effects are as follows:
①Inhibit calcium-dependent phosphodiesterase activity, increase the cAMP content that relaxes vascular smooth muscle, thereby relaxing vascular smooth muscle and increasing cerebral blood flow.
②Enhance red blood cell deformability, reduce blood viscosity, inhibit platelet aggregation, and thus improve blood fluidity and microcirculation.
③Promote brain tissue to absorb glucose and promote the metabolic conversion of monoamines in the brain.
④In the case of cerebral ischemia, it can inhibit the increase of lactic acid in the brain, increase the ATP content, inhibit the production of lipid peroxides in the brain, and delay the occurrence of cerebral ischemic spasm, so it has the effect of improving brain metabolism and protecting brain function.
Indications
1. Neurology: various cerebrovascular diseases and their sequelae, etc.
2. Cardiology: coronary heart disease, arteriosclerosis and abnormal blood viscosity, etc.
3. Ophthalmology: various visual impairments caused by poor fundus blood circulation, etc.
4. Otorhinolaryngology: hearing loss, tinnitus, vestibular dysfunction, etc.
5. Neurosurgery: rehabilitation treatment of brain function after various cranial and brain surgeries.
