Fig. 6
First total synthesis of xestospongienes E–H. a Synthesis of (R)-1c; b Synthesis of (S)-1c; c Total synthesis of xestospongiene F; d Total synthesis of xestospongiene G; e Total synthesis of xestospongiene H; f Total synthesis of xestospongiene E. Reagents and conditions: i. NaH (1.0 equiv.), THF, 0 °C then rt; then MeI (1.2 equiv.), 0 °C ~rt; then HCl (aq., 3.0 M), MeOH, rt; ii. Fe(NO3)3∙9H2O (10 mol%), TEMPO (10 mol%), NaCl (10 mol%), O2 balloon, DCM, rt; iii. CBr4 (1.5 equiv.), PPh3 (3.0 equiv.), DCM, 0 °C; iv. methyl 4-oxobutanoate 2k (1.5–1.7 equiv.), CuBr2 (20 mol%), dioxane, 120 °C; v. LiOH∙H2O (1.5 equiv.), EtOH/H2O = 1:1, 90 °C; vi. AuCl(LB-Phos) (10 mol%), AgOTs (10 mol%), CHCl3, −30 °C
