Composition #2: Kesting, Julie R., Tolderlund, Inge-Lise., Pedersen, Anders F., Witt, Matthias., Jaroszewski, Jerzy W., Staerk, Dan. Piperidine and Tetrahydropyridine Alkaloids from Lobelia siphilitica and Hippobroma longiflora. JOURNAL OF NATURAL PRODUCTS, 2009, vol. 72, no. 2, p. 312–315. DOI: 10.1021/np800743w.
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