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Alkaloids from amphibian skin: a tabulation of over eight-hundred compounds.
A diverse array of biologically active, lipid-soluble alkaloids have been discovered in amphibian skin. Such alkaloids include the following: the steroidal samandarines from salamanders, theExpand
Spatial and temporal patterns of alkaloid variation in the poison frog Oophaga pumilio in Costa Rica and Panama over 30 years.
The results of this study indicate that chemical defense in a dendrobatid poison frog is dependent on geographic location and habitat type, which presumably controls the abundance and nature of alkaloid-containing arthropods. Expand
A review of chemical ecology in poison frogs
There is variation in nearly every attribute of the dendrobatids system and some of the challenges associated with unraveling the complexities of this model system are described. Expand
Oribatid mites as a major dietary source for alkaloids in poison frogs
The results of this study indicate that mites are a significant arthropod repository of a variety of alkaloids and represent a major dietary source of alkAloids in poison frogs. Expand
Geographic and Seasonal Variation in Alkaloid-Based Chemical Defenses of Dendrobates pumilio from Bocas del Toro, Panama
Individual alkaloid variation in the dendrobatid poison frog D. pumilio is examined among seven populations and between two seasons on Isla Bastimentos, located in the Bocas del Toro archipelago of Panama, illustrating that chemical defense in this species can vary on a small spatial and temporal scale. Expand
Homobatrachotoxin in the genus Pitohui: chemical defense in birds?
Three passerine species in the genus Pitohui, endemic to the New Guinea subregion, contain the steroidal alkaloid homobatrachotoxin, apparently as a chemical defense, suggesting that birds and frogs independently evolved this class of alkaloids. Expand
Evidence for biosynthesis of pseudophrynamine alkaloids by an Australian myobatrachid frog (pseudophryne) and for sequestration of dietary pumiliotoxins.
Pseudophryne frogs appear to biosynthesize PSs, but to sequester into skin dietary PTXs, the first evidence indicating that certain frogs are capable of synthesizing rather than merely sequestering alkaloids. Expand
Indolizidine 239Q and quinolizidine 275I. Major alkaloids in two Argentinian bufonid toads (Melanophryniscus).
Structures of two major alkaloids 239Q and 275I were determined by mass, FTIR, and NMR spectral analysis as 5Z,9Z-3-(1-hydroxybutyl)-5-propylindolizidine and 6Z,10E-4,6-di(pent-4-enyl) quinolIZidine, respectively. Expand
Coumarins and carbazoles from Clausena excavata exhibited antimycobacterial and antifungal activities.
Four known coumarins, dentatin (1), nor-dentatin (2), clausenidin (3) and xanthoxyletin (5), and six known carbazole derivatives, 2-hydroxy-3-formyl-7-methoxycarbazole (10) and clauszoline J (11) were isolated from Clausena excavata and demonstrated no cytotoxicity against KB and BC-1 cell lines. Expand