# Luminescent Properties and Cytotoxic Activity of 2-phenylbenzoxazole Fluorosulfate Derivatives

## TL;DR

This paper explores new 2-phenylbenzoxazole fluorosulfate compounds that show promising anticancer and fluorescent properties.

## Contribution

The study introduces fluorosulfate derivatives with both antiproliferative and photoluminescent properties.

## Key findings

- BOSo, an ortho-substituted derivative, showed significant cytotoxicity against MCF-7 breast cancer cells.
- BOSo's structure resembles known hER and HER2 inhibitors like tamoxifen.
- A para-fluorosulfate derivative achieved up to 64% quantum yield in acetonitrile.

## Abstract

The synthesis of 2-phenylbenzoxazole fluorosulfate derivatives was carried out using the SuFEx reaction. To study the anticancer properties of the obtained compounds, the cell lines PC-3 (obtained from prostate adenocarcinoma), BT-474, and MCF-7 (both obtained from breast carcinoma) were used. The cytotoxicity on murine 3T3L1 embryonic was also investigated. Among the tested compounds, the ortho-substituted fluorosulfate derivative (BOSo) exhibited significant cytotoxicity against MCF-7 cells. The biological findings are consistent with molecular docking results, which revealed a structural similarity between BOSo and known inhibitors of hER and HER2 receptors—tamoxifen and SYR127063. Therefore, BOSo shows promise as a potential therapeutic agent with antiproliferative properties. The photoluminescent characteristics of the fluorosulfate derivatives were examined in the solid state, in acetonitrile solution and in PBS, with the highest quantum yields reaching up to 64% for the para-fluorosulfate derivative in acetonitrile. Overall, these compounds demonstrate considerable potential for the development of new multifunctional molecular tools that combine biological activity with fluorescent properties.