Dimeric piperidinoquinoline alkaloids from the seeds of Chimonanthus salicifolius

A chemical investigation of extracts from the seeds of Chimonanthus salicifolius has led to the isolation of four new dimeric piperidinoquinoline alkaloids (1-4) and one new dimeric tryptamine alkaloid (5), along with five known alkaloids (6-10). Notably, compounds 3 and 4 were identified as two unusual dimeric piperidinoquinoline alkaloid-fatty acid hybrids. The new structures were elucidated using HRESIMS, NMR, and ECD spectroscopic techniques. The isolated compounds were subjected to cytotoxicity testing against HCT-116, HT-1080, and A549 cell lines. Compound 5 exhibited moderate activity against the HCT-116 and HT-1080 cell lines, with IC50 values of 44.59 ± 2.08 μM and 37.39 ± 2.31 μM, respectively.