ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A detailed study of the reaction of catharanthine N-oxide and vindoline has been carried out employing various conditions. Under optimum conditions, which involve low temperatures and trifluoroacetic anhydride as reagent, 3′, 4′-dehydrovinblastine (XIII, R = COOCH3), in reasonable yields is essentially the exclusive product. However two additional products, 18′ (epi)- 3′, 4′-dehydrovinblastine (XIV, R = COOCH3) and 1′-hydroxy- 3′, 4′-dehydrovinblastine (XVI, R = COOCH3) are also often isolated.The reaction, which follows the course of a Polonovski-type fragmentation process, has been extended to the N-oxide derivatives of dihydrocatharanthine and decarbomethoxycatharanthine to provide again a series of bisindole alkaloid derivatives, also vinblastines. A mechanistic rationale is provided to explain the various results obtained.
Additional Material:
6 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19760590824
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