Dendrobates indolizidine from

Daly, J. W., Tokuyama, T., Fujiwara, T., Highet, R. J., Karle, I. L. A new class of indolizidine alkaloids from the poison frog, Dendrobates tricolor. X-ray analysis of 8-hydroxy-8-methyl-6-(2 -methylhexylidene)-1-azabicyclo[4.3.0]nonane, J. Am. Chem. Soc. 1980, 102, 830-836. 

The isolation and characterisation from a Panamian population of Dendrobates pumilio Schimdt of indoiizidine 223A [25], formerly identified as 1,4-dipropyl quinolizidine [5], established a new type of class A alkaloids the 5,6,8-trisubstituted indolizidines. 

The alkaloid 249H, Fig. (11), was isolated from the skin extracts of the poisonous frog Dendrobates auratus of the Isla Taboga of the Pacific coast of Panama [26]. A sample containing only traces of impurities was obtained by successive column chromatography of the methanolic skin extract. H and C NMR spectroscopy and correlation spectra were only consistent with a branched substituent, the first to be reported for simple indolizidines isolated from frog skin, and an unusual cw-fused trisubstituted indolizidine nucleus. 

Indollzidine alkaloids. A group of alkaloids from various classes based on the bicyclic ring system of in-dolizidine. They differ in structure, biogenesis, and occurrence thus, the indolizidine ring system has very little value as a characterizing structural. The I. a. include the pumiliotoxins (Dendrobates alkaloids), poly hydroxy alkaloids such as swainsonineand cas-tanospermine, Elaeocarpus alkaloids, Securinega alkaloids, Tylophora alkaloids, and the Ipom(o)ea alkaloids. 

Edwards MW, Daly JW, Myers CW (1988) Akaloids from a Panamanian poison frog, Dendrobates speciosus identification of pumiliotoxin-A and allopumiliotoxin class alkaloids, 3,5-disubstituted indolizidines, 5-substituted 8-methylindolizidines, and a 2-methyl-6-nonyl-4-hydroxypiperidine. J Nat Prod 51 1188-1197 Emsley L, Bodenhausen G (1989) Self-refocusing effect of 270° Gaussian pulses. Applications to selective two-dimensional exchange spectroscopy. J Magn Reson 82 211-221... 

Several indolizidine alkaloids are known from Dendrob-ium (Orchidaceae). Dendroprimine (34) is representative of these compounds (Howard and Micheal, 1986). 

An indolizidine alkaloid from the frog, Dendrobates tricolor... 

Highet, R. j., j. W. Daly, T. Fujiwara, and T. Tokuyama Indolizidine alkaloids from poison frogs of Dendrobates spp. Planta Medica 39, 260—261 (1980). 

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