Synthesis and Biological Evaluation of a Valinomycin Analog Bearing a Pentafluorophenyl Active Ester Moiety
作者:Lucia D’Accolti、Nunzio Denora、Gianluigi La Piana、Domenico Marzulli、Zuzanna S. Siwy、Caterina Fusco、Cosimo Annese
DOI:10.1021/acs.joc.5b02219
日期:2015.12.18
A valuable analog of the K+-ionophore valinomycin (1), bearing a pentafluorophenyl ester moiety, has been obtained by Selective reaction between the tertiary hydroxyl moiety of analog 2 (available from valinomycin hydroxylation) and the isocyanate group of pentafluorophenyl N-carbonyl glycinate (3) catalyzed by bis(N,N-dimethylformamide)dichlorodioxomolybdenum (VI) LC-HRMS studies show that analog 4 undergoes easy derivatization under mild conditions by reaction with OH- and NH2-containing compounds. Mitochondrial depolarization assays suggest that 4 acts as a K+-ionophore, provided that the glycine carboxyl group is appropriately masked.
Antitumor Potential of Conjugable Valinomycins Bearing Hydroxyl Sites: In Vitro Studies
作者:Rosa M. Iacobazzi、Cosimo Annese、Amalia Azzariti、Lucia D’Accolti、Massimo Franco、Caterina Fusco、Gianluigi La Piana、Valentino Laquintana、Nunzio Denora
DOI:10.1021/ml400300q
日期:2013.12.12
Following our pioneering studies on the direct and efficient introduction of derivatizable hydroxyl handles into the valinomycin (VLM, 1) structure, a K+-ionophore with potent antitumor activity, the ensuing conjugable analogues (HyVLMs 2, 3, and 4) have herein been compared to the parent macrocycle for their potential antiproliferative effects on a panel of cancer cell lines, namely, human MCF-7, A2780, and HepG2, as well as rat C6 cells. On the basis of IC50 values, we find that hydroxyl analogues 3 and 4 are only moderately less active than 1, while analogue 2 experiences a heavily diminished activity. Cytofluorimetric analyses of MCF-7 cells treated with HyVLM.s suggest that the latter depolarize mitochondria, thus retaining the typical VLM behavior. It is likely that C6 cells, for which the exceptionally potent cytotoxicity of VLM has never reported previously, follow the same fate, as evidenced by alteration of mitochondrial morphology upon incubation with each ionophore.