Selective Synthesis of Hydroxy Analogues of Valinomycin using Dioxiranes
作者:Cosimo Annese、Immacolata Fanizza、Cosima D. Calvano、Lucia D’Accolti、Caterina Fusco、Ruggero Curci、Paul G. Williard
DOI:10.1021/ol201971v
日期:2011.10.7
A synthesis of representative monohydroxy derivatives of valinomycin (VLM) was achieved under mild conditions by direct hydroxylation at the side chains of the macrocyclic substrate using dioxiranes. Results demonstrate that the powerful methyl(trifluoromethyl)dioxirane 1b should be the reagent of choice to carry out these key transformations. Thus, a mixture of compounds derived from the direct dioxirane
Site-dependent biological activity of valinomycin analogs bearing derivatizable hydroxyl sites
作者:Cosimo Annese、Daniela I. Abbrescia、Lucia Catucci、Lucia D'Accolti、Nunzio Denora、Immacolata Fanizza、Caterina Fusco、Gianluigi La Piana
DOI:10.1002/psc.2571
日期:2013.12
Valinomycin (VLM, 1) is a K+ ionophore cyclodepsipeptide capable of depolarizing mitochondria and inducing apoptosis to several mammalian cell types, including a number of tumor cell lines. With the aim of creating VLM‐based ligand‐targeted anticancer drugs that may selectively convey VLM to pathological cells, we have previously introduced derivatizable hydroxyl handles into the VLM structure, allowing
Valinomycin(VLM,1)是一种K +离子载体环二肽,能够使线粒体去极化并诱导多种哺乳动物细胞类型(包括多种肿瘤细胞系)的凋亡。为了创建可选择性地将VLM传递至病理细胞的基于VLM的,针对配体的抗癌药物,我们先前已将可衍生的羟基手柄引入VLM结构,从而可以访问带有三聚体的单羟基VLM(HyVLM)三元文库。d- Hyi,d -Val或l的异丙基侧链上的OH基-Val残基(分别为模拟量2-4)。在本文中,已根据其可改变分离的大鼠肝脏线粒体功能的能力评估了可缀合的HyVLM保留的生物活性水平。在1-10 nM的HyVLM和20或125 mM KCl介质中进行的实验表明,羟基相对于VLM降低HyVLM的效力,其程度取决于羟基化涉及的分子位点。另一方面,估计每个类似物与Na +,K +和Cs +的配合物的稳定常数(在25°C的甲醇中)表明,HyVLM很好地保留了VLM结合特征,除了Na
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.