D. Vinblastine
Synonyms Vincaleukoblastine; VLB; 29060-LE;
Biological Source It is obtained from Vinca rosea Lin.. (Apocynaceae).
Chemical Structure
Isolation It may be isolated from Vinca rosea Linn., either by the method suggested by Noble et al*. or by Gorman et al.,**
Characteristic Features
1. It is obtained as solvated needles from methanol having mp 211-216°C.
2. Its specific optical rotation [α]26D + 42° (chloroform).
3. It has uvmax (ethanol): 214, 259 nm (log ε4.73, 4.21).
4. It is soluble in alcohols, chloroform, acetone, ethyl acetate and is practically insoluble in water and petroleum ether.
Identification Tests It forms derivatives as given below:
1. Vinblastine Sulphate (C46H58N4O9.H2SO4) (Exal, Vebe, Velban): It is obtained as crystals mp 284-285°C. Its physical parameters are: [α]26D – 28° (C = 1.01 in methanol); pKa1 5.4; pKa 27.4. It has uvmax (methanol): 212, 262, 284, 292 nm (log € 4.75, 4.28, 4.22, 4.18). One part is soluble in 10 parts of water, 50 parts of chloroform; very slightly soluble in ethanol; and practically insoluble in ether.
2. Vinblastine Dihydrochloride Dihydrate (C46H58N4O9.2HCl.2H2O): It is obtained as crystals that decompose at 244-246°C.
Uses
1. The alkaloid is used for the treatment of a wide variety of neoplasms.
2. It is also recommended for generated Hodgkin’s disease, lymphocytic lymphoma, hystiocytic hymphoma, mycosis fungoides, advanced testicular carcinoma, Kaposi's sarcoma, and choriocarcinoma and lastly the breast cancer unresponsive to other therapies.
3. It is effective as a single entity, however, it is normally given along with other neoplastic agents in combination therapy for the increased therapeutic effect without any noticeable additive toxicity.
4. It arrests mitosis at the metaphase.
5. It is found to be effective in the acute leukemia of children.
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* Noble et al. Ann. N.Y. Acad. Soc. 76, Art 3, 892-894 (1958)
** Gorman et al. J. Am. Chem. Soc., 81, 4745, 4754, (1959).
