Diarylheptanoid analogues from the rhizomes of Zingiber officinale and their anti-tumour activity

Eight previously undescribed diarylheptanoids (1-8), together with fifteen known analogues (9-23), were isolated from the rhizomes of Zingiber officinale. Their structures were unambiguously determined by comprehensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. It is worth mentioning that 1-3 are the first reported structures of diaryl ether heptanoids in Z. officinale, whereas 15-17 were isolated from Zingiber for the first time. Furthermore, a gene enrichment analysis of the interacting targets indicated that diarylheptanoids were mainly associated with the anti-tumor activity by affecting DNA damage signaling pathway. The results showed that 6, 16-19 had remarkable inhibitory effects against five tumor cell lines (A549, HepG2, HeLa, MDA-MB-231, and HCT116) with IC50 values ranging from 6.69-33.46 mu M, and showed down-regulating the expression of ATR (ataxia telangiectasia mutated and RAD3-related) and CHK1 (checkpoint kinase 1) levels in HCT116 and A549 cell lines. Our studies not only enrich the structural diversity of diarylheptanoids in nature, but also discover several natural compounds for anti-tumor agents.