Indolizidine alkaloids bioactivity

A complete review on the synthesis of indolizines has appeared <2000HOU(10)745>. This chapter is an extension of the reviews in CHEC(1984) <1984CHEC-I(4)443> and CHEC-II(1996) <1996CHEC-II(8)237>, mainly focusing on the development of synthetic methods aimed at the synthesis of natural alkaloids and important bioactive compounds containing the indolizidine nucleus. 

An impressive number of alkaloids and bioactive compounds containing the indolizidine skeleton have been synthesized. These belong principally to three classes which will be separately analyzed. Other natural products not belonging to these classes will be collected in section 11.09.8.3. 

The skin of neotropical frogs of the Dendrobatidae family has been a rich source of bioactive compounds [42] such as the alkaloids epibatidine, batrachotoxins, histrionicotoxin, and indolizidines. The latter have been investigated due to their activity as noncompetitive blockers of the nicotinic receptor channels [43]. Because only small amounts are available and due to their pronounced physiological activity, these alkaloids are important targets for organic synthesis [44]. Since... 

The indolizidine and quinolizidine alkaloids covered in this review proved to have relevant bioactivity. 

The bioactivity of castanospermine and related alkaloids continues to inspire chemists to devise new synthetic routes to the alkaloid, as well as to iimumerable structural, stereochemical and other analogs. The ensuing discussion deals only with reported syntheses of the four natural products 239-242. For syntheses of other reported stereoisomers of the indolizidine-l,6,7,8-tetraols (Fig. 4), the following references should be consulted (-)-l-epicastanosp>ermine (243) (194), ( )-7-epicastanospermine (195) and (15,6S, 75, 87f,8a7 )-7-epicastanospermine (244) (196),... 

Lourenfo, A. M. Maximo, P. Ferreira, L. M. Pereira, M. M. A. Indolizidine and Quinohzidine Alkaloids. Structure and Bioactivity. In Studies in Natural Product Chemistry, Vol. 27, Atta-ur-Rahman, Ed. Elsevier Amsterdam, 2002 pp 233—298. 

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