Dendrobates pumilio Panamanian population

Three novel tricyclic alkaloids (222, 236, and 252A) were isolated from skin extracts of a Panamanian population of the poison frog Dendrobates pumilio. Amidine structures were proposed for these alkaloids in 1987 based on mass spectral and nuclear magnetic resonance spectral analyses (77). However, recent gas chromatographic-FTIR spectra showed that these three alkaloids could not be amidines, since they had no absorption around 1630 cm where amidines show an intense absorption. A reexamination of the nuclear magnetic resonance spectral data and acquisition of new data led to revised structures 153). The simplest member (222) is a spiropentanopyrrolizidine oxime, whereas 236 is the corresponding... 

Alkaloid from skin extracts of the Panamanian poison frog Dendrobates speciosus. Also detected as a trace constit. in certain populations of D. pumilio. [(x] + 39 (c, 0.2 in MeOH). 

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