Abstract
Clarification of the confusion previously reported will prevent the proliferation of scientific mistakes and consequently avoid a negative domino effect due to today’s rapid divulgation of information. The complex structures of asperjinone, (+)-pestalazine B and aquatolide have been revised in recent years and these studies have been included herein. However, there may be some misunderstanding on simpler structures such as 2,3,4,5-tetrahydro-1,5-benzoxazepine-3-ol (3), which has been mistaken for 3,4-dihydro-2H-3- hydroxymethyl-1,4-benzoxazine (1); both compounds have been synthesized via different routes with the aim of clarifying the structural elucidation. In a subsequent paper the misunderstanding between the six- and seven-membered structures has been repeated. We also redress some points of earlier papers on these compounds, and on the chemical conditions for the preparation of intermediates of the target molecules 1 and 3. The situation can be even more critical with important economical consequences when the mistakes affect patented structures, because the company's competitors might attack the validity of the patents. The principal researchers of any laboratory from which the work originates have an absolute and unavoidable responsibility to ensure the quality of the data from their laboratories, even if the main work is done by experienced postdocs. Both imaginative detective work using Mass Spectra, 2D Nuclear Magnetic Resonance data and chemical synthesis still have important roles to play in the process of solving molecular puzzles. The investigation of structural mistakes is very instructive and facilitates a deeper understanding of the complicated logical process for deducing molecular scaffolds.
Keywords: Aquatolide, Asperjinone, Benzoxazepine, Benzoxazine, Computer-assisted structure elucidation (CASE), Famotidine, Natural products, (+)-Pestalazine B.
Graphical Abstract