Scheme 1. Summary of synthesis of YC-1 (1). Route a: synthesis by Teng et al. (2002); route b: synthesis by Collot et al. and Hering et al. (1999, 2006); route c: synthesis by Meng et al. (2017); route d: synthesis by Carla et al. (2008). Reagents and conditions: (a) FeCl3; (b) PhCH2NHNH2, HOAc; (c) Pb(OAc)4; (d) BF3Et2O; (e) Ca(BH4)2; (f) NaBH4, MeOH, rt; (g) Pd2(dba)3, AsPh3, DMF; (h) POCl3, DMF, 0 °C to 80 °C; (i) I2, KOH, DMF; (j) BnBr, t-BuOK, Bu4NI, THF; (k) Pd(PPh3)4, NaHCO3, DME, reflux; (l) ArCH2Br, t-BuOK, THF, 0 °C to rt; (m) THF, −80 °C; (n) MnO2, CH2Cl2; (o) (i) TsNHNH2, HCl, MeOH; (ii) Cu2O, i-AmOH, reflux; (p) Mg, MeOH; (q) MsCl, Et3N, CH2Cl2; (r) furan, n-BuLi, THF, −78 °C to 0 °C; (s) HO–NH2 HCl, pyridine, MeOH, reflux.
