2.3.2. Xanthoquinodin B10 (**2**)

Yellow, amorphous solid; [α] 20 <sup>D</sup> + 474◦ (*c* 0.005, MeOH); UV (MeOH) λmax (log ε) 199 (4.5), 274 (3.8), 353 (4.3); CD (*c* 1.6 <sup>×</sup> 10–3 M, MeOH) <sup>λ</sup>max (Δε) 228 (+15.91), 264 (+2.69), 320 (+15.51), 359 (+14.38); 1H-NMR and 13C-NMR see Table 1; ESI-MS: *m*/*z* 643.19 (M <sup>−</sup> H)<sup>−</sup> and 645.24 (M + H)+; HRESIMS *m*/*z* 645.1967 (M + H)<sup>+</sup> (calculated for C35H33O12, 645.1967).


**Table 1.** One-dimensional nuclear magnetic resonance (1D-NMR) spectroscopic data for compounds **1**–**4** (in CDCl3).
