Determination of the absolute stereochemistry of ( +)-solaniol

The absolute stereochemistry of ( +)-solaniol (5,8-dihydroxy-7-(2-hydroxypropyl)-2-methoxy-6-methyl-1,4-naphthoquinone) ( 1 ) was deduced to be S using Mosher’s method. Our result did not accord with the R configuration of ( +)-solaniol recently proposed by Maharjan et al., but agreed with the S configuration determined by X-ray crystallographic analysis by Kyekyeku et al. In addition, complete and unambiguous assignments of 13 C NMR signals for 1 are reported. Graphic abstract