Development and evaluation of fused benzazole analogs of anti-melanoma agent HA15.

In line with our recent discovery of an efficient anticancer thiazolebenzenesulfonamide framework HA15 () based on a remarkable endoplasmic reticulum stress inducement mode of action, we report herein a series of innovative constrained HA15 analogs, featuring four types of bicylic derivatives. The structure-activity relationship analysis, using a cell line assay, led us to identify a novel version of HA15: a new benzothiazole derivative () exhibiting important anti-melanoma effect against sensitive and resistant melanoma cells. Meanwhile, compound induced a significant tumor growth inhibition with no apparent signs of toxicity. These results consistently open new directions to improve and develop more powerful anticancer therapeutics harboring this type of fused framework.