E N D
A B C D E F G H Supplementary data 1. Structural assignment of celastrol isolated from T. regelii was elucidated by nuclear magnetic resonance (1H-NMR, 13C-NMR, COSY, HMQC, DEPT and HMBC). (A) 1H NMR spectrum of celastrol. (B) 13C NMR spectrum of celastrol. (C) DEPT 90 spectrum of celastrol. (D) DEPT 135 spectrum of celastrol. (E) HOMO COSY spectrum of celastrol (F) HMQC spectrum of celastrol. (G) HMBC spectrum of celastro. (H) Important HMBC correlations of celastrol.