Structure elucidation of norlaureline and puterine, new noraporphine alkaloids from Guatteria elata

The structures of norlaureline (1) and puterine (4), new noraporphine alkaloids isolated from Guatteria elata (Annonaceae), were established by interpretation of the optical rotation, uv, ir, pmr, and mass spectral data of their N-acetyl derivatives. Proposed structures were confirmed by transformation of 1 and 4 to laureline (3) and pukateine methyl ether (6), respectively.