Determination of the absolute configuration of the chiral biaryl system in the streptonigrin antibiotics by exciton coupled circular dichroic spectroscopy

Article abstract of DOI:10.1016/S0040-4020(97)10008-4

The absolute configuration of the chiral phenylpyridyl segment of the Actinomycete antibiotic streptonigrin (1) is defined as R by analysis of the exciton coupled circular dichroic spectra of selected derivatives, The absolute configuration of the co-occurring 10'-O-demethylstreptonigrin (2) is assigned as R by chiroptical correlation with streptonigrin. Circular dichroic spectroscopy indicates that the related phenylpyridone streptonigrone (5) is either achiral or a racemate.