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Nux Vomica Alkaloids. Strychnine and Brucine. Biosynthetic Origin. terpenoid indole alkaloids from Trp (from shikimate pathway via anthranilic acid) have a tryptamine fragment and a C9 or C10 residue 3 types of indole alkaloids: Corynanthe , Aspidosperma and Iboga. Biosynthetic Origin.
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Nux Vomica Alkaloids Strychnine and Brucine
Biosynthetic Origin • terpenoid indole alkaloids • from Trp (from shikimate pathway via anthranilic acid) • have a tryptamine fragment and a C9 or C10 residue • 3 types of indole alkaloids: Corynanthe, Aspidosperma and Iboga
Natural Source • found in Strychnos nux-vomica (Fam. Loganiaceae) • strychnine (1.2 % ), brucine (1.6 %) • also contains igasuric acid & loganin, a glycoside • Strychnos ignatia – more strychnine
Pharmaceutical Applications: Strychnine • appetite stimulant and general tonic in small doses • Specific Medicine Nux Vomica and Tinctura Nucis Vomicae • pesticide/ vermin killer • used in synthetic chemistry as optically-active bases to achieve optical resolution of racemic acids (along with brucine)
Mechanism of Action • an antagonist of glycine, a major inhibitory neurotransmitter in the mammalian nervous system
Mechanism of Action • increased reflex action, increased rate of respiration, and enlargement of the capacity of the lungs • increased force, rate, and volume of the pulse, raised arterial pressure, increased sharpness to sight, hearing, and smell, and general irritation
Side Effects • extremely poisonous (100 mg is fatal ) • uneasiness and restlessness, suffocation, tremors, convulsions, risus sardonicus, opisthotonos, pain, weariness, spasms • death usually taking place after three or four convulsions • death may occur during the interval from exhaustion, or paralytic asphyxia, or during the grip upon the respiratory muscles and the heart from cramp asphyxia
Analogues • Strychnine: -- brucine, dimethoxy analogue -- bisquaternary dimers • Brucine: