
%0 Journal Article
%A Crowley, HC 
%A Culvenor, CCJ 
%T The Alkaloids of <I>Heliotropium supinum</I> L., with Observations on Viridifloric Acid
%J Australian Journal of Chemistry
%D 1959/12/01
%V 12
%N 4
%P 694-705
%K 
%R https://doi.org/10.1071/CH9590694
%U https://www.publish.csiro.au/paper/CH9590694 
%X Heliotropium supinum L. contains the pyrrolizidine alkaloids supinine, heliosupine, and echinatine as major bases. Two minor alkaloids, although not obtained in a pure state, are shown to be esters of trachelanthic acid and viridifloric acid, respectively, with 7-angelylheliotridine. The N-oxide of 7-angelylheliotridine, also isolated from the total crude base, is thought to be an artefact.Viridifloric acid is shown to be (-)-erythro-2,3-dihydroxy-4-methylpentane-3-carboxylic acid. Its melting point is markedly influenced by minute amounts of tenacious impurities. The ester of supinidine and viridifloric acid has been prepared from these component substances. 
