title: Alkaloids from dendrobatid frogs: structures of two omega-hydroxy congeners of 3-butyl-5-propylindolizidine and occurrence of 2,5-disubstituted pyrrolidines and a 2,6-disubstituted piperidine.
abstract: Forty alkaloids were detected and characterized from skin extracts of high- and low-elevation populations of the poison frog Dendrobates histrionicus from northwestern Colombia. Combined gc/ms with NH3 or ND3 in a chemical ionization mode detected protonated parent ions and determined the number of exchangeable NH and OH hydrogens. Six previously unknown dendrobatid alkaloids were characterized. Two were 2,5-disubstituted pyrrolidines, which included pyrrolidine 197B, a trans-2-butyl-5-pentylpyrrolidine, while a third was a 2,6-dipentylpiperidine. Indolizidines 239AB and 239CD had the same relative configuration as the parent alkaloid 223AB [(5E,9E)3-butyl-5-propylindolizidine] and contained, respectively, a omega-hydroxy group in the propyl or butyl side chain. The profiles of alkaloids in the new northern populations of D. histrionicus are typical of the species in containing a set of about eight histrionicotoxins, in marked contrast to a related species, Dendrobates lehmanni, which does not contain histrionicotoxins.
mesh_terms: D000470:Alkaloids / Q000032:analysis* / Q000302:isolation & purification; D000818:Animals; D001001:Anura; D008401:Gas Chromatography-Mass Spectrometry; D007212:Indolizines / Q000032:analysis*; D010880:Piperidines / Q000032:analysis*; D011759:Pyrrolidines / Q000032:analysis*; D012867:Skin / Q000032:analysis*; D013045:Species Specificity
chemical_list: D000470:Alkaloids; D007212:Indolizines; D010880:Piperidines; D011759:Pyrrolidines