Synthesis of polymeric bismuth chlorido hydroxamato complexes; X-ray crystal structure and antibacterial activity of a novel Bi(III) salicylhydroxamato complex

Building a Green, Robust, and Efficient Bi-MOF Heterogeneous Catalyst for the Strecker Reaction of Ketones

In this work, we present the new [Bi₁₄(μ₃-O)₉(μ₄-O)₂(μ_3–OH)₅(3,5-DSB)₅(H₂O)₃]·7H₂O, BiPF-4 (bismuth polymeric framework—4) MOF, its microwave hydrothermal synthesis, as well as its behavior as a heterogeneous catalyst in the multicomponent organic Strecker reaction. The BiPF-4 material shows a three-dimensional (3D) framework formed by peculiar inorganic oxo-hydroxo-bismutate layers connected among them through the 3,5-dsb (3,5-disulfobenzoic acid) linker. These two-dimensional (2D) layers, built by junctions of Bi7 polyhedra SBU, provide the material of many Lewis acid catalytic sites because of the mixing in the metal coordination number. BiPF-4 is a highly robust, green, and stable material that demonstrates an excellent heterogeneous catalytic activity in the multicomponent Strecker reaction of ketones carried out in one-pot synthesis, bringing a reliable platform of novel green materials based on nontoxic and abundant metal sources such as bismuth.

In this work, we present the new [Bi₁₄(μ₃-O)₉(μ₄-O)₂(μ₃₋OH)₅(3,5-DSB)₅(H₂O)₃]·7H₂O, BiPF-4 (bismuth polymeric framework—4) MOF, its microwave hydrothermal synthesis, as well as its behavior as a heterogeneous catalyst in the multicomponent organic Strecker reaction.

Medicinal chemistry and biomedical applications of bismuth-based compounds and nanoparticles

Bismuth as a relatively non-toxic and inexpensive metal with exceptional properties has numerous biomedical applications. Bismuth-based compounds are used extensively as medicines for the treatment of gastrointestinal disorders including dyspepsia, gastric ulcers and H. pylori infections. Recently, its medicinal application was further extended to potential treatments of viral infection, multidrug resistant microbial infections, cancer and also imaging, drug delivery and biosensing. In this review we have highlighted the unique chemistry and biological chemistry of bismuth-209 as a prelude to sections covering the unique antibacterial activity of bismuth including a description of research undertaken to date to elucidate key molecular mechanisms of action against H. pylori, the development of novel compounds to treat infection from microbes beyond H. pylori and the significant role bismuth compounds can play as resistance breakers. Furthermore we have provided an account of the potential therapeutic application of bismuth-213 in targeted alpha therapy as well as a summary of the biomedical applications of bismuth-based nanoparticles and composites. Ultimately this review aims to provide the state of the art, highlight the untapped biomedical potential of bismuth and encourage original contributions to this exciting and important field.

Dual anticancer and antibacterial activities of bismuth compounds based on asymmetric [NN'O] ligands

Two new bismuth(III) complexes, [BiL¹Cl₂] (1) and [BiL²Cl₂] (2), in which L¹ is (2-hydroxy-4-6-di-tert-butylbenzyl-2-pyridylmethyl)amine and L² is 2,4-diiodo-6-((pyridine-2-ylmethylamino)methyl)phenol, were synthesized and characterized by elemental and conductivity analyses, atomic absorption spectrometry, infrared and ¹H NMR spectroscopies. The molecular structure of 1 reveals that the NN'O ligand forms a 1:1 complex with bismuth through coordination via the nitrogen of the aliphatic amine, the nitrogen of the pyridine ring and the oxygen of the phenolate. The coordination sphere is completed with two chloride anions in a distorted square pyramidal geometry. Bismuth exhibits the same coordination mode in compound 2. The cytotoxic activity of 1 and 2 was investigated in a chronic myelogenous leukemia cell line. The complexes are approximately three times more potent than the corresponding free ligands, with the IC₅₀ values 0.30 and 0.38 μM for complex 1 and 2, respectively. To address the cellular mechanisms underlying cell demise, apoptosis was quantified by flow cytometry analysis. From 0.1 μM, both complexes induce apoptosis and there is a remarkable concentration-dependent increase in the population of cells in apoptosis. The complexes were also evaluated against Gram-positive and Gram-negative bacteria. Both inhibited the bacterial growth in a concentration-dependent way, with remarkable activity in some of the tested strains, for example, complex 2 was more active than its free ligand against all bacterial strains and approximately fourteen times more potent against S. dysenteriae and S. typhimurium.

Novel antimony(iii) hydroxamic acid complexes as potential anti-leishmanial agents

The synthesis, characterisation and anti-leishmanial activity of novel Sb(iii) hydroxamato and Sb(iii) hydroxamato/hydroximato complexes are reported.