The structure elucidation of a new bromophenol metabolite from Polysiphonia urceolata by experimental and DFT theoretical methods

A new bromophenol metabolite was obtained from the red alga Polysiphonia urceolata. The structure and absolute stereochemistry of this bromophenol were elucidated to be (5S, 10S)-2,7-dibromo-3,8-dihydroxy-5,10-dimethoxyl-5,10-dihydro-chromeno[5,4,3-cde]chromene on the basis of spectroscopic techniques and DFT theoretical analysis. The NMR spectra have been successfully reproduced from the theoretical calculations by means of the GIAO method. This bromophenol metabolite from marine source is reported for the first time.