Pseudopterosins and Seco-Pseudopterosins: Compilation and Revision of Conflicting NMR Data, Names, Numbering Systems and Structural Elucidation

Abstract

The present review is focussed on the structural elucidation of the bicyclic and tricyclic diterpenoid title compounds isolated from Pseudopterogorgia species, displaying a direct structural relationship with the biosynthetic precursor GGPP (regular isoprenoid skeletons). A compilation of 1H and 13C NMR spectroscopic data is presented grouped by similar spin systems. Apparent inconsistencies or potential missassignments are discussed, pointing out convenient revisions of data assignment to improve structure correlations. Some hemisynthetic intermediates in the structural elucidation process are included, as well as data of representative synthetic compounds.

Marine natural products

“…A comprehensive review of the structures, naming, and NMR assignments of pseudopterosin and seco-pseudopterosin has been published, highlighting inconsistencies in the primary literature. 507 The introduction of primary amino groups onto Gram-positive only antibiotics of the pseudopterosin aglycone family has been demonstrated to convert the compounds into broad spectrum antibiotics with activity towards Gram-negative bacteria. 508 The structure of the intriguing Pseudopterogorgia elisabethae metabolite (+)-aberrarone 1273 has been conrmed by synthesis, with the core 5-5-5 fused ring system constructed using a Au-catalysed cascade.…”