CA4 and cancer: In another study with trimethoxyphenyl moiety, a series of the seven-membered ring (benzothiazepine), which is similar to CA-4 analogs (St.10 and St.11; Figure 4), and compound St.61 (Figure 11) was the most potent compound among this series with significant antiproliferative activities against MCF-7, HeLa, Ht29, and A549 cancer cell lines.