Mass spectra and stereochemistry of some macrocyclic pyrrolizidine alkaloids

Conclusions On the basis of the results of a comparison of the mass spectra of macrocyclic pyrrolizidine alkaloids with a known configuration of the side chain (trichodesmine, monocrotaline) with the spectra of incanine, crispatine, and fulvine a hypothesis has been put forward on the relative positions of the substituents at C₂ and C₃ in the molecules of the three latter compounds.Order of the Red Banner of Labor Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–44, January–February, 1974.