Nuciferol C, a new sesquineolignan dimer from Cocos nucifera L.: bioactivity and theoretical investigation

Nuciferol C (NC), an undescribed dimer of nuciferol B (NB), was isolated from the endocarp of Cocos nucifera L. The planar structure of NC was determined using 1D- and 2D-NMR spectroscopy as well as high resolution MS spectrometry. The absolute configuration was concluded based on analysis of NOESY spectra. NC showed cytotoxic activity against colon cancer cells (CaCo-2) with an IC₅₀ value of 76 μM, and significantly decreased the expression of human epidermal growth factor receptor (EGFR) and tumor necrosis factor alpha (TNF-α) in CaCo-2 as compared with untreated cells by 39% and 33%, respectively (p < 0.05). In addition, NC exhibited anti-herpes simplex virus (HSV-I) activity with an IC₅₀ value of 23 μM. In silico study of NC was implemented at three levels: density functional theory (DFT) was used to study its electronic properties, molecular mechanics was used to estimate the docking results, and finally, molecular dynamic simulation was used to study the behavior and stability of NC inside the active site of the target protein of HSV-1.