(+)-N-Formylnorglaucine Rotamers from Unonopsis stipitata Diels

• Published in: Helvetica chimica acta Vol. 99; no. 7; pp. 494 - 498
• Main Authors: da Silva, Felipe M. A., da Silva Filho, Francinaldo A., de Lima, Bruna R., de Almeida, Richardson A., Mendonça, Dácio M., Pereira Junior, Raimundo C., Dutra, Lívia M., Barison, Andersson, Koolen, Hector H. F., de Souza, Afonso D. L., Pinheiro, Maria Lúcia B.
• Format: Journal Article
• Language: English
• Published: Zürich Blackwell Publishing Ltd 01-07-2016; Wiley Subscription Services, Inc
• Subjects: (+)-N-Formylnorglaucine; Annonaceae; Aporphine alkaloid; Rotamers; Unonopsis stipitata
• ISSN: 0018-019X; 1522-2675
• DOI: 10.1002/hlca.201600030

(+)‐N‐formylnorglaucine (1), an aporphine alkaloid containing a formyl group linked to the heterocyclic nitrogen, was isolated from the leaves of Unonopsis stipitata, an Amazon medicinal plant. The chemical structure was characterized based on 1D‐ and 2D‐NMR spectroscopy and HR‐ESI‐MS. NMR spectra revealed that 1 is composed of two rotamers (1a and 1b) in a ratio of approximately 2:1. In addition, the fragmentation behavior of 1 displayed an unusual fragmentation pattern compared to regular aporphine alkaloids. Thus, this compound is reported for the first time as a natural product in this study.