Figure 1

Absolute configuration of compound 1. (a) Chemical structure of compound 1. (b) Key 1H−1H COSY (blue) and HMBC (red arrows) correlations of compound 1. (c) Key ROESY (arrow) correlations of compound 1. (d) X-ray ORTEP drawing of compound 1.
Absolute configuration of compound 1. (a) Chemical structure of compound 1. (b) Key 1H−1H COSY (blue) and HMBC (red arrows) correlations of compound 1. (c) Key ROESY (arrow) correlations of compound 1. (d) X-ray ORTEP drawing of compound 1.