Caffeic acid (CA), ferulic acid (FA) and caffeic acid phenethyl ester (CAPE) have a broad anticancer effect on various cell lines. In this study, nine ferulic and caffeic acid-based 1,2,4 and 1,3,4 oxadiazole molecular hybrids were synthesized and their cytotoxic activity was evaluated mainly against Glioblastoma (GBM) cell lines. Compounds 1 and 5 exhibited the highest inhibitory activity against three different GBM cell lines (LN229, T98G, and U87), without toxicity to healthy human mesenchymal stem cells (hMSC). In addition, their cytotoxicity was also evaluated against three additional cancer cell lines and more inhibitory results were found than GBM cell lines. The IC50 values of compound 5 in U87, T98G, LN229, SKOV3, MCF7, and A549 cells were determined as 35.1, 34.4, 37.9, 14.2, 30.9, and 18.3 μM. In the light of biological activity studies, the developed compounds have a high potential to lead studies for the development of new drug candidates for the treatment of cancer.

Leishmaniasis is a neglected parasitic disease that is widely seen in more than 60 countries worldwide, including Turkey and its subcontinental region. There are several chemotherapy agents for the treatment of leishmaniasis, including pentavalent antimonials—i.e., sodium stibogluconate (Pentostan) and meglumine antimoniate (Glucantim), pentamidine, conventional amphotericin B deoxycholate, miltefosine, paramomycin (aminosidine), and liposomal amphotericin B. However, these therapies are usually unsatisfactory due to dose-limiting toxicity issues and limited efficacy. Furthermore, resistance gained by parasites endangers future success of these therapies. Addressing these issues, the development of novel drugs with high efficacy has a vital importance. Latest studies have shown that bisnaphthalimidopropyl (BNIP) derivatives display high activity against Leishmaniasis parasites by selectively targeting parasitic sirtuin proteins and interacting with DNA. Despite the promising anti-parasitic activity, the low solubility and toxicity on human macrophages are the limitations to overcome. This study describes the new synthesis strategies for existing—i.e., BNIPDaoct and BNIPDanon—and novel BNIP derivatives differing in respect of their alkyl linker chain lengths. The new synthesis approach provides certain advantages compared to its existing alternatives reported in the literature. The proposed methodology does not only decrease the number of synthesis steps and production time of BNIPDaoct and BNIPDanon, but also provides higher yields, thereby making the synthesis highly cost-effective.