The polyether ionophore salinomycin has recently gained attention due to its exceptional ability to selectively reduce the proportion of cancer stem cells within a number of cancer cell lines. Efficient single step strategies for the preparation of hydroxamic acid hybrids of this compound varying in N-and O-alkylation are presented. The parent hydroxamic acid, salinomycin-NHOH, forms both inclusion complexes and well-defined electroneutral complexes with potassium and sodium cations via 1,3-coordination by the hydroxamic acid moiety to the metal ion. A crystal structure of an cationic sodium complex with a noncoordinating anion corroborates this finding and, moreover, reveals a novel type of hydrogen bond network that stabilizes the head-to-tail conformation that encapsulates the cation analogously to the native structure. The hydroxamic acid derivatives display down to single digit micromolar activity against cancer cells but unlike salinomycin selective reduction of ALDH + cells, a phenotype associated with cancer stem cells was not observed. Mechanistic implications are discussed.
The title compound is based on a trinuclear {Fe3(μ-O)4} core with an angular arrangement of the FeIII ions that can be explained by geometrical restrictions of two bulky ligands each coordinated to all the metal centres.
Rationale: Carbides, including tellurium carbides (TeC), play crucial roles in diverse applications, but TeC synthesis has not been described in the literature. Laser ablation synthesis (LAS) coupled with mass spectrometry was used here for in situ TeC clusters synthesis and identification of the reaction products to better understand TeC formation. Methods: Laser desorption ionization time-of-flight mass spectrometry (LDI-TOFMS) was used to generate the TeC clusters and determine their stoichiometry via computer modeling of isotopic patterns.Results: A simple one-pot procedure was developed for Te-nanodiamond nanocomposite preparation. A suspension of fine-powdered Te was mixed with a suspension of nanodiamonds (both in acetonitrile), and the resulting precipitated nanocomposite was suitable for the synthesis of TemC n clusters using LDI. Various unary and binary clusters were formed. The stoichiometry of the novel TemC n clusters, determined via computer modeling of isotopic patterns, is reported here for the first time.
Conclusions:The Te-nanodiamond composite was found to be the most suitable precursor for the generation of TemC n clusters. In total, 35 binary TemC n clusters were identified, when several of them were not obtained using commercial TeC material.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.