About this Biochemistry, Genetics and Molecular Biology article

Identification of isomeric tropane alkaloids from Schizanthus grahamii by HPLC-NMR with loop storage and HPLC-UV-MS/SPE-NMR using a cryogenic flow probe by Stefan Bieri; Emmanuel Varesio; Jean-Luc Veuthey; Orlando Muñoz; Li-Hong Tseng; Ulrich Braumann; Manfred Spraul; Philippe Christen is a Biochemistry, Genetics and Molecular Biology article available to read on EtoBox.

Two fully automated HPLC-NMR methods are reported and compared for the structure elucidation of four isomeric tropane alkaloids from the stem-bark of an endemic Chilean plant, Schizanthus grahamii Gill. (Solanaceae). The first approach interfaced a conventional HPLC column to NMR by means of a loop storage unit. After elution with a mobile phase consisting of deuterated water and standard protonated organic solvents, the separated analytes were momentarily stored in a loop cassette and then transferred one-at-a-time to the NMR flow probe for measurements. The second strategy combined HPLC with parallel ion-trap MS detection and NMR spectroscopy using an integrated solid-phase extraction (SPE) unit for post-column analyte trapping. The SPE cartridges were dried under a gentle stream of nitrogen and analytes were sequentially eluted and directed to a cryogenically cooled flow-probe with an NMR-friendly solvent. The structures of the four isomeric alkaloids, 3alpha-senecioyloxy-7beta-hydroxytropane, 3alpha-hydroxy-7beta-angeloyloxytropane, 3alpha-hydroxy-7beta-tigloyloxytropane and 3alpha-hydroxy-7beta-senecioyloxytropane, were unambiguously determined by combining NMR assignments wit

Author

Stefan Bieri; Emmanuel Varesio; Jean-Luc Veuthey; Orlando Muñoz; Li-Hong Tseng; Ulrich Braumann; Manfred Spraul; Philippe Christen

Publisher

John Wiley and Sons; Wiley (John Wiley & Sons); John Wiley & Sons Inc.; Wiley (ISSN 0958-0344)

Published

2006

Language

EN

Field

Biochemistry, Genetics and Molecular Biology (Life Sciences)