The first total synthesis of (+)-amabiline, an unsaturated pyrrolizidine alkaloid from Cynoglossum amabile, is reported. This convergent, enantioselective synthesis proceeds in 15 steps (10-step longest linear sequence) in 6.2% overall yield and features novel methodology to construct the unsaturated pyrrolizidine or (-)-supinidine core.

Analysis of Swiss honeys for pyrrolizidine alkaloids Christina Kast*, Arne Dübecke, Verena Kilchenmann, Katharina Bieri, Michael Böhlen, Otmar Zoller, Gudrun Beckh and Cord Lüllmann Swiss Bee Research Centre, Agroscope, Schwarzenburgstrasse 161, 3003 Bern, Switzerland. Quality Services International GmbH, 28199 Bremen, Germany. Institute of Pollen Analysis K. Bieri GmbH, Talstrasse 23, 3122 Keh...

Seven pyrrolizidine alkaloids (PAs) have been isolated from Lithospermum canescens and their structures determined by spectroscopical methods. Besides the known lycopsamine, O7-acetyl-lycopsamine and O7-acetylintermedine four new PAs were found. Their structures are O7-(3-hydroxy-3-methyl-butanoyl)-O9-(+)-trachelanthoyl-heliotridine (= O7-(3-hydroxy-3-methyl-butanoyl)-rinderine = canescine), O7...

Four young Chinese women took daily doses of an unidentified 'Indian' herbal tea as treatment for psoriasis. Three (one of whom died), developed ascites, hepatomegaly and biochemical abnormalities within 19-45 days. The fourth patient discontinued herbal tea after 21 days when she developed a skin rash. Two patients had portal hypertension, while all had liver histology showing features of veno...

Over four hundred alkaloids in amphibian skin have been detected and structures from twenty different classes have been elucidated. These include batrachotoxins, histrionicotoxins, pumiliotoxins, epibatidine, pyrrolidines, piperidines, decahydroquinolines, pyrrolizidines, indolizidines, quinolizidines and tricyclic gephyrotoxins, pyrrolizidine oximes, pseudophrynamines, coccinellines and cyclop...

Alkaloid profiles of five Senecio species (Asteraceae), including S. ambiguus subsp. ambiguus, S. ambiguus subsp. nebrodensis, S. gibbosus subsp. bicolor, S. gibbosus subsp. gibbosus, and S. gibbosus subsp. cineraria, were studied. Eleven pyrrolizidine alkaloids were identified and their content was evaluated by GLC-MS and GLC analysis. Otosenine and florosenine were found to be the major alkal...

Um novo alcalóide denominado Helindicina (1), e o conhecido licopsamina (2) foram isolados das raízes de Heliotropium indicum (Boraginaceae). As estruturas foram estabelecidas tendo como base um amplo estudo de 1D e 2D RMN (COSY, HMBC, HMQC, NOESY) e HREIMS. Este representa o primeiro relato de um alcalóide contendo um anel lacônico no gênero Heliotropium. Estes alcalóides mostraram moderada at...

Alkaloid profiles of two Egyptian Senecio species (Senecio aegyptius var. discoideus and S. desfontainei) in addition to a cultivated species (S. cineraria) were studied using capillary GLC and GLC-mass spectrometry with respect to pyrrolizidine alkaloids (PAs). Four alkaloids were identified in S. aegyptius var. discoideus, 8 in S. desfontainei and 13 in S. cineraria. Some of these alkaloids h...