NSCLC Structure-activity Relationship (SAR) Study of Diisothiocyanates for Antiproliferative Activity on A549 Human Non-small Cell Lung Carcinoma (NSCLC)

Isothiocyanate functional group (-N=C=S) is widely accepted as an important moiety for anti- cancer effects of naturally occurring isothiocyanate compounds (ITCs). Herein, a series of diisothiocyanate (diITCs) derivatives were synthesized and evaluated in antiproliferative assays on A549 human non-small cell lung cancer and IMR90 human foetal lung cell lines for structure-activity relationship (SAR) and cancer cell selectivity studies. Results showed that aliphatic and benzylic diITCs were more cytotoxic to A549 cells than natural ITCs; benzyl isothiocyanate (BITC) and phenyl isothiocyanate (PITC), and a currently available anticancer drug; etoposide. Aromatic diITCs were not as active. Notably, most of the diITCs reported in this work were significantly more selective than etoposide to inhibit proliferation of the cancer cells (A549) over the normal cells (IMR90). This study demonstrated a guideline to modify chemical structures of diITCs for anti-NSCLC agents.