Our study showed that PAIB-SOs bearing an n-hexyl or an n-octyl groups were generally inactive at their maximum solubility in our vehicle, while PAIB-SOs bearing an n-pentyl group maintained an antiproliferative activity in the nanomolar range and a high selectivity ratio (1–3 logs) towards CYP1A1-expressing BC cells. The gene discussed is CYP1A1; the disease is breast cancer.