Development of a general and efficient route to highly lipophilic benzoxazole-2ylphosphonates and their antineoplastic properties

摘要

As a continuation of our efforts to discover and develop the 2-substituted-5,7-di-tert-butyl-2,3-dihy-drobenzo[d]oxazol-2-ylphosphonate series of apoptosis inducers as potential anticancer agents, we explored new substitutions at the 2- and 3-positions of the oxazole ring to identify the development of antitumor candidates. This modification, in combination with synthesizing their relevant 2-benzoxazaphosphole 2-oxides and enamino-phosphonates, resulted in obtaining an ensemble of 13 new phosphonates in high yields (70-76 %). The synthesized phosphonates were analyzed using the reversed-phase, high performance liquid chromatography method for the lipo-philicity measurement (logK) as a prediction tool. Later on, selected compounds were evaluated as antitumor agents at a dose of 10 μmol cm~(-3) against breast, prostate, and melanoma carcinoma cell lines. The results were discussed in terms of structure-activity relationships.