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The copper(I) iodide/1,4-bis(2-hydroxy-3,5-di-tert-butylbenzyl)piperazine (CuI-L2) system catalyzed the cross-coupling reactions between aryl halides and aqueous ammonia in water to produce primary aromatic amines in good yields. The protocol was simple and efficient, avoiding the need for inert atmosphere, additional base, or other additives. Key words: copper, catalysis, cross coupling, water chemistry, aqueous ammonia, primary arylamine. Le systeme iodure de cuivre(I)/1,4-bis(2-hydroxy-3,5-di-ieri-butylbenzyl)piperazine (CuI-L2) catalyse les reactions de couplages croisees entre les halogenures d'aryles et une solution aqueuse d'ammoniaque pour conduire a la formation d'amines aromatiques primaires avec de bons rendements. Le protocole est simple et efficace, il ne necessite pas d'atmosphere inerte, de base additionnelle ou d'autres additifs. Mots-cles : cuivre, catalyse, couplage croise, chimie dans l'eau, solution aqueuse d'ammoniaque, arylamine primaire., Introduction Ammonia is an attractive source of nitrogen in organic synthesis owing to its great abundance and low cost. (1) In recent years, the palladium- or copper-catalyzed coupling of aryl [...]

With the consideration of the dynamic role of microRNAs (miRNAs) in breast cancer, miRNAs may serve as therapeutic targets, helping to prevent development of therapy resistance, maintain stable disease, and prohibit metastatic spread. We identified the differentially expressed breast cancer-related gene ribonucleotide reductase subunit M2 (RRM2) as the study focus through microarray expression profiles. Next, the upstream regulatory microRNA (miR)-4500 of RRM2 was predicted using bioinformatics website analysis, and their binding was verified by a dual luciferase reporter gene assay. The regulatory effects of miR-4500 on breast cancer cell proliferation, apoptosis, migration, invasion, and capillary-like tube formation of endothelial cells were assessed by gain- and loss-of-function experiments. The experimental data revealed that miR-4500 was downregulated, whereas RRM2 was upregulated in breast cancer cells. Mechanistic analysis revealed that miR-4500 downregulated the RRM2 expression to inactivate the mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, miR-4500 exerted anti-tumor effects by targeting RRM2 through suppression of the MAPK signaling pathway in vitro, evidenced by attenuated cancer cell migration and invasion and capillary-like tube formation of endothelial cells. The in vivo experiments further corroborated in vitro results. Collectively, overexpressed miR-4500 could downregulate RRM2 and inhibit activation of the MAPK signaling pathway, thus attenuating breast cancer cell proliferation, invasion, migration, and angiogenesis and promoting breast cancer cell apoptosis., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)