84314-27-2Relevant academic research and scientific papers
The Crystal Structure of (S)-(-)-6-Bromo-5,7-dihydroxy-8-methyl-2-phenyl-2,3-dihydro-4H-1-benzopyran-4-one and a 13C N.M.R. Study of (+/-)Cryptostrobin and Related Substances. Revision of the Structures of the Natural Products (+/-)-Lawinal, Unonal, 7-O-Methylu
Byrne, Lindsay T.,Cannon, Jack R.,Gawad, Dilip H.,Joshi, Balawant S.,Skelton, Brian W.,et al.
, p. 1851 - 1858 (2007/10/02)
The crystal structure of (S)-(-)-6-bromo-5,7-dihydroxy-8-methyl-2-phenyl-2,3-dihydro-4H-1-benzopyran-4-one (11) has been determined by X-ray diffraction from diffractometer data at 295 K and refined by block diagonal least squares to a residual of 0.050 (810 'observed' reflections).Crystals of (11) are tetragonal, P43212, a 7.849(4), c 46.83(2) Angstroem, Z 8.The crystallographic data are consistent with the S configuration previously proposed for (-)-cryptostrobin (10).The 13C n.m.r. spectra of (+/-)-cryptostrobin and (+/-)-strobopinin also lead to the structures (1) and (6), respectively.This work has enabled the structures proposed for the natural products (-/+)-lawinal, unonal, 7-O-methylunonal and isounonal to be revised to (8), (14), (15) and (12), respectively.
