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.

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WE have evidence that the resolution of l,l,ltrifluoropropan-2-01 recently reported by Crawford,2 is not complete. The asymmetric reduction of l,l,l-trifluoropropan-2-0ne by the Grignard reagent from ( +)-l-chloro-2-phenylbutane gave (-)-1,1,1-trifluoropropan-2-o1 (63% yield) which was purified by gas chromatography, [a]:6 -2.20 & 0.02 (neat, 1 = 0.5).