Toxicarioside A. A new cardenolide isolated from Antiaris toxicaria latex-derived dart poison. Assignment of the 1H- and 13C-NMR shifts for an antiarigenin aglycone

Abstract

Bioassay-guided fractionation of the chloroform/methanol extract of a dart poison from Indonesian Borneo (Kalimantan), derived from Antiaris toxicaria latex, has led to the isolation of a new cardenolide, toxicarioside A [1]. The structure of 1 was deduced by analysis of spectroscopic data and has led to the first assignment of the 1H- and 13C-NMR shifts for an antiarigenin aglycone. The bioassay employed to isolate cardenolide 1 involves inhibition of Na+/K+-ATPase and mimics the suspected mode of action of these “cardiac-glycoside” toxins.