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In this review, the most important complex compounds of ruthenium, gold, vanadium, chromium, bismuth, technetium were selected, and then their most important applications were described in medicine. Ruthenium has been identified as a metal with potential medical use, useful in cancer chemotherapy. The possibility of using its chemical behavior by developing complexes activated for cytotoxic activity through a mechanism of reduction in tumor tissue was discovered. Among the new anti-cancer drugs based on complex compounds, gold compounds have gained a lot of interest. This is due to their strong inhibitory effect on the growth of cancer cells and the observation that many compounds inhibit the enzyme thioredoxin reductase. This enzyme is important for the proliferation of cancerous tissues, and its inhibition is associated with the release of anti-mitochondrial effects. Clinical tests have shown that vanadium compounds can be used as anti-diabetic drugs with low toxicity. However, the therapeutic concentration range is very narrow, just a few micromoles of the compound are enough to cause apoptosis, necrosis and inflammation of healthy cells. Chromium improves the glucose system in people with hypoglycemia or hyperglycemia. Vanadium compounds mainly used to create potential drugs are inorganic compounds such as vanadates(V), vanadyl cation(IV), vanadium oxide(V) and a number of compounds containing organic ligands. Among the metal complexes, chromium(III) picolinate has successfully become a nutrient used to prevent high blood sugar levels. One of the most commonly used bismuth(III) compounds is bismuth subsalicylate. It is one of the few bismuth compounds regularly used to treat various gastrointestinal complaints, including duodenal ulcers. 99mTc injected into the body, depending on its chemical form and molecular structure, concentrates in the examined organ and emits a quantum that allows imaging of the organ through flat scintigraphic or emission processes. The role of complex compounds in medical imaging is largely based on the creation of radiopharmaceuticals for early detection of diseases and cancer radiotherapy. Radiopharmaceuticals are radionuclide-containing drugs and are routinely used in nuclear medicine to diagnose or treat a variety of diseases.
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SMP (shape-memory polymers) is an innovative class of programmable materials responsive to various stimuli. They are attracting increasing attention regarding possible new inventions, industrial use, and overall polymer research. After a brief introduction, this article examines the conventional shape-memory effect, methods of fabrication of shape memory polymers, and molecular and structural requirements for SMP to function. The shape memory behavior of such polymers is thoroughly presented, with the focus being on the thermo- and photo-induced SME. The uses in biomedical and industrial areas are also discussed.
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In - vitro methods of determination of the antioxidant activity of complex compounds are very interesting and not fully investigated areas of knowledge from the borderline of chemistry and biology. Methods used for determination of the activity of antioxidant complex compounds are modified due to the conditions of the experiments in which they should be carried out, e.g. reactions at physiological pH. Civilization diseases, stress related to the fast pace of life and increasing requirements of our lives cause the formation of free radicals in our body, i.e. particles characterized by a high reactivity. The methods of determination of the antioxidant activity of complexes discussed in this work apply tests carried out in laboratory conditions - in - vitro.
EN
Isocyanides are the most unusual and unique group in organic chemistry. They possess an unusual valence structure and reactivity. Isocyanides are the only class of stable organic compounds with a formal divalent carbon, which allows them to be the subject of virtually all reactions in organic chemistry. It can be either an electrophile, a nucleophile, a caraben and a radical acceptor. We distinguish between naturally occurring and synthetically produced isocyanides. Both groups of isocyanides have become recently the subject of scientific interest.
EN
The complex compounds containing metal ions are a group of compounds widely used in medicine. More and more metals are also being used to create cancer drugs or to help with other very serious diseases. Anticancer drugs are a particular use of complex compounds. Many thousands of platinum(II) compounds have been synthesized in cancer therapy, but only six of them have found use in the treatment of cancer. The most popular and the most commonly used compound is cisplatin, it has become the basis for the treatment of bladder, cervical, head, esophagus and many cancers occurring in children. The mechanism of action of platinum(II) and platinum(IV) compounds against cancer cells is to inhibit DNA replication, then RNA transcription and stop the G2 phase of the cell cycle and lead to programmed cell death or apoptosis. Coordination compounds containing more than one metal ion in their composition open new possibilities in the fight against cancer. Pt-DNA connections created by compounds containing at least two metal atoms are different from those formed by cisplatin. The basic dinuclear structure allows for great flexibility in forming DNA-DNA or DNA-protein bonds. The cobalt(III) complexes began to be used to image areas of hypoxia in cancer cells. It is believed, that cobalt(III) complexes undergo bioreduction, which leads to the release of the labile cobalt(II) complex and one or more bioactive ligands. Studies on nitro-Co(III) complexes containing acetylacetone and a nitrogen mustard ligand have shown that it is a particularly effective anti-cancer drug. Due to the fact that many people have cancer new effective anti-cancer drugs with low toxicity and no side effects are still being sought.
EN
Recently, there has been an increased interest in designing new catalytic systems for olefin polymerization reactions. Scientists' research focuses on the design of cheap, green precatalysts based on transition metal ions, i.e. vanadium(III), and vanadium(IV). This review summarizes recent reports on the catalytic properties of vanadium coordination compounds in olefin polymerization reactions. Additionally, the latest publications on using heterogeneous metal-organic frameworks (MOFs) based on vanadium in the coordination polymerization of olefins will be presented.
EN
In 1964, J.C. Bailat Jr. was one of the first scientists who use coordination polymers in his research. He established the rules of structure and the composition of compounds containing metal ions and organic ligands connected by coordination bonds to form layered or chain structures. He compared inorganic compounds belonging to polymeric species with organic polymers. The term Metal Organic Frameworks (MOF) was first used in the publication by О. M. Yaghia. Crystalline, microporous structures contain rigid organic ligands (used interchangeably: organic building blocks) that bind metal ions. This is called reticular synthesis. MOF surface area values usually range from 1000 to 10000 m2/g-1, thus exceeding the area values of traditional porous materials such as zeolites and carbons. Metal Organic Frameworks create porous three-dimensional structures, unlike coordination polymers. Inorganic minerals from the aluminosilicate group are used in the widespread heterogeneous catalysis and processes such as: adsorption and ion exchange, while compared to Metal Organic Frameworks, shows a lower potential than zeolites, moreover, the design of structures is less precise and rational due to the lack of shape, size and control functionalization of pores. To date, MOF are the most diverse and most numerous class of porous materials. All aspects have made them ideal structures for storing fuels such as hydrogen and methane. They are perfect for catalytic reactions and are good materials for capturing pollutants, e.g. CO2. The number of publications on coordination polymers (CP), Metal Organic Frameworks (MOF) or a group of hybrid compounds (organic-inorganic) increased tenfold at the turn of 2005, which proves the growing interest in this field by scientists around the world. MOF diversity in terms of structure, size, geometry, functionality and flexibility of MOF has led to the study of over 20,000 different MOF’s over the past decade. The search for new materials consists of combining molecular building blocks with the desired physicochemical properties. To produce a solid, porous material that can be used in the construction of a "molecular scaffold", rigid organic moieties, which are described in the literature as rods, must be combined with multi-core, inelastic inorganic clusters that act as joints (also called SBU secondary building units). By design, multi-core cluster nodes are able to impart thermodynamic stability through strong covalent bonds and mechanical stability due to coordination bonds that can stabilize the position of metals in the molecule. This property contrasts with those of the unstable single coordination polymers. The size and most importantly the chemical environment of the resulting voids are determined by the length and functions of the organic unit. Therefore, adjusting the appropriate properties of the material is made by appropriate selection of the starting materials. The isoretical method made it possible to use MOF structures with large pores (98 Á and low densities (0.13 g/cm3). This method involves changing the size and nature of Metal Organic Frameworks without changing the topology of their substrate. Thanks to this, it was possible to include large molecules such as vitamins (e.g. B12) or proteins (e.g. green fluorescence protein) into their structure and use the pores as reaction vessels. The thermal and chemical stability of many MOFs has made them amenable to functionalization by post-synthetic covalent organic complexes with metals. These properties make it possible to significantly improve gas storage in MOF structures and have led to their extensive research into the catalysis of organic reactions, activation of small molecules such as hydrogen, methane and water, gas separation, biomedical imaging and conductivity. Currently, methods of producing nanocrystals and MOF super crystals for their incorporation into specialized devices are being developed. Crystalline structures of MOF’s are formed by creating strong bonds between inorganic and organic units. Careful selection of MOF components produces crystals of giant porosity, high thermal and chemical stability. These features allow the interior of the MOF to be chemically altered to separate and store gases. The uniqueness of MOF materials is that they are the only solids to modify and increase the particle size without changing the substrate topology.
EN
This article describes the in-vivo methods of studying the antioxidant properties of complex compounds. The reduced glutathione (GSH) method, which uses the reactivity of the reduced form of GSH with free radicals, is among the described methods. Further the in-vivo methods are based on the use of antioxidant enzymes such as glutathione peroxidase, glutathione S-transferase, superoxide dismutase, catalase. These types of enzymes occur naturally in the human body and they are responsible for the inactivation of free radicals, e. g. superoxide dismutase catalyzes the reaction of disproportionation of superoxide anion radical to water and oxygen. The next in-vivo methods described in this article use y-glutamyl transpeptidase and glutathione reductase, which are components of the antioxidant mechanism occurring in an organism. The last method described in this work relates to the lipid peroxidation, which is determined by the concentration of dimalonic aldehyde.
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The report focuses on the antidiabetic, also termed insulin-like, effect of various vanadium and chromium derivatives, proposed mechanisms of their activity, their use in in vivo and in vitro studies, as well as in diabetic patients, their toxicity and effectiveness in controlling clinical signs of diabetes. Studies indicate that compounds of vanadium and chromium is necessary for regulation of carbohydrate and lipid metabolism mainly due to increasing the number of insulin receptors and its activation by phosphorylation. Some authors believe that compounds of chromium(III) deficiency can lead to glucose intolerance and symptoms of type 2 diabetes. However, due to methodological limitations of many clinical studies, the statements of major diabetes associations concerning recommendation of various vanadium and chromium derivatives supplementation in individuals with diabetes and obesity still remains negative. Additional studies are urgently needed to elucidate the mechanism of action of chromium and vanadium compounds and its role in the prevention and control of diabetes.
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