E. Vincristine
Synonyms Leurocristine; VCR; LCR.
Biological Sources It is also obtained from Vinca rosea Lin., (Catharanthus roseus G. Don) belonging to the natural order Apocynaceae.
Chemical Structure Please see the chemical structure under Vinblastine. It may also be named as: 22-Oxovincaleukoblastine.
Isolation Vincristine may be isolated from Vinca rosea Linn., by the method suggested by Svoboda.*
Characteristic Features
1. It is obtained as blades from methanol having mp 218-220°C.
2. Its specific optical rotation [α]25D + 17°; [α]25D + 26.2° (ethylene chloride); pKa: 5.0, 7.4 in 33% DMF.
3. It has uvmax (ethanol): 220, 255, 296 nm (log am 4.65, 4.21, 4.18).
Identification Tests
Vincristine Sulphate (C46H56N4O10.H2SO4) (Vincrex, Oncovin, Vincosid, Kyocrystine): Its crystals are obtained from ethanol and is found to be unstable.
Uses
1. Vincristine sulphate is recommended for the treatment of acute lymphocytic leukemia, and in combination therapy in Hodgkin's disease, lymphosarcoma, reticulum cell sarcoma, neuroblastoma, Wilm's tumour and rhabdomyosarcoma.
Note: Viucristine sulphate being highly unstable; therefore, its refregerated storage in sealed ampules is absolutely essential.
2. It is broadly used as an antineoplastic agent.
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* Svobada, Lyoydia, 24, 173 (1961)
