Polypropylene is a semicrystalline thermoplastic addition polymer used in several applications, such as plastic parts for many industries, consumer product packaging, special devices like living hinges, and textiles. Thanks to its excellent properties, it could be used only or in a nanocomposite system. This article presents the different types of nanoparticles used for the enhancement of thermo-mechanical and physical behaviors of PP nanocomposites. The analysis of morphologies and thermo-mechanical behaviors of virgin PP nanocomposites are described. Moreover, this paper also discusses the improvements of properties of waste PP by nanoparticle incorporation. Finally, the last section of the paper covers a case study about influence of clay nanoparticles on waste PP based nanocomposites.
Cancer is among the most severe risks to the global human population. The enduring crisis of drug-resistant cancer and the limited selectivity of anticancer drugs are significant roadblocks to its control and eradication, requiring the identification of new anticancer entities. The stable aromatic nature, reversible redox properties, and low toxicity of ferrocene revolutionized medicinal organometallic chemistry, providing us with bioferrocene compounds with excellent antiproliferative potential, which has been the focus of persistent efforts in recent years. Substituting the aryl/heteroaryl core for ferrocene in an organic molecule alters its molecular characteristics, including solubility, hydro-/lipophilicity, as well as bioactivities. Ferrocifen (ferrocene analogues of hydroxytamoxifen) has shown antiproliferative potential in both hormone-dependent (MCF-7) and hormone-independent (MDA-MB-231) breast cancer cells. It is now in pre-clinical trials against malignancies. These entities operate through various targets, some of which have been revealed and activated in response to product concentrations. They also react to the cancer cells by diverse mechanisms that can work in concert or in isolation, depending on signaling pathways that promote senescence or death. The behavior of ferrocene-containing hybrids with a range of anticancer targets is explained in this chapter.
Nitrogenated heterocycles take part in the structure of many natural products and agents with important biological activity, such as antiviral, antibiotic and antitumor drugs. For this reason, heterocyclic compounds are one of the most desired synthetic targets nowadays. In this review work, the literature related to the preparation of polyheterocyclic compounds by using the intramolecular Povarov reaction will be collected. The Povarov reaction is a process in which aromatic amines, carbonyl compounds and olefins or acetylenes participate to give rise to the formation of the nitrogenated compounds. Then, intramolecular Povarov reactions to carry out these syntheses are described according to the key processes involved; catalytic reactions with transition metals will be included discussing the reaction mechanisms and examining the effect of catalysts and solvents in the preparation of the products, thus reflecting the synthetic potential of this strategy. Moreover, applications of prepared compounds will also be considered.
Ionic liquids (ILs) are receiving increased enticement from synthetic organic chemists; world-wide due to their extraordinary physicochemical properties. The wide-ranging applications of ionic liquids as solvents and catalysts in organic synthesis are mainly due to their non-volatile nature which arises from very low vapor pressures. Since the past few decades, researchers have explored the efficacy of these designer solvents as green substitutes of toxic and volatile organic solvents for a variety of value added synthetic organic reactions. Furthermore, the tremendous potential of ILs as catalysts is also worth mentioning. Unlike organic solvents of comparable polarity, they often act as catalysts in various organic reactions. Thus, the present chapter aims at observing and exploring the application of ionic liquids as solvents and catalysts in various synthetic organic reactions. The green chemistry aspects of the solvent as well as the catalytic use of ionic liquids in order to develop environmentally benign organic synthesis is also the focus of discussion in this chapter.
Barbituric acid is an organic compound containing a pyrimidine heterocyclic skeleton. It is a water-soluble and odorless compound. Barbituric acid served as a starting material for many barbiturate drugs. The variable properties of the products achieved from barbituric acid motivate organic chemists to investigate its chemistry and current developments have suggested it by multicomponent reactions (MCR). Barbituric acid and its derivatives, commonly known as barbiturates, are important in pharmaceutical chemistry because they are fascinating building blocks for synthesizing biologically active compounds. The first barbiturate to be prepared was Barbital (5, 5-diethyl barbituric acid), and it is hypnotic and sedative and was used as an anxiolytic and sleeping aid. Barbituric acid derivatives act on the central nervous system and are used as sedatives, anxiolytics, anticonvulsants, and hypnotics. Recent investigations show that barbituric acid derivatives may have applications in matrix metalloproteinases, inhibiting collagen-ase-3 (MMP-3), anti-invasive, recombinant cytochrome P450 enzymes, fungicides, methionine aminopeptidase-1 (MetAP-1), herbicides, antibacterial, anti-tumor antiangiogenic, antioxidant, antiviral, and HIV-1 integrase inhibitors. Furthermore, recent literature accounts have shown that barbituric acid derivatives may also perform as immune modulators. Barbituric acid has been exploited in designing and preparing various types of carbocyclic and heterocyclic compounds. An extensive range of multicomponent reactions utilize barbituric acid as a starting material. By using the Knoevenagel condensation reaction, a wide range of barbiturate drugs, that act as central nervous system depressants can be synthesized using barbituric acid. Barbituric acid is a precursor in the laboratory production of riboflavin (vitamin B2 ).
The contemporary era of studying superhydrophobic surfaces began in 1997, when Neinhuis and Barthlott discovered the self-cleaning qualities of the lotus effect. Corrosion of steel represents an important industrial issue with well-known negative economic and environmental consequences. The protection of steel objects during service operations is an inexhaustible research subject because of the steel's high demand in the industry. Anticorrosive coatings have aided in extending the life of the material without impairing its bulk qualities. The microporous structure of polymers allows corrosive ions to pass at the coating–metal interface, resulting in poor serviceability. Advanced structural modifications, such as polymeric nanocomposites, have been used to solve these disadvantages. Organic-inorganic nanocomposites are employed as outstanding anti-corrosive coatings to provide steel constructions' service longevity. Superhydrophobic nanocomposite coatings tend to be one of the most promising methods for avoiding corrosion in steel. Various nanostructured fillers have the ability to significantly improve the corrosion-barrier efficiency of polymeric coatings. Superhydrophobicity in nature will be briefly addressed to provide a comprehensive study. This chapter focuses on introducing the anticorrosive properties of superhydrophobic coatings. It gives an overview of present and advanced research developments, such as graphene nanocomposite surfaces.
Semiconducting metal oxide nanomaterials are the future potential materials for biomedical applications. Zinc oxide (ZnO) nanomaterials are developed by using the organic synthesis process for excellent biocompatibility, selectivity, sensitivity, good chemical stability, non-toxicity, and fast electron transfer properties. They have a high surface-to-volume ratio that performs proper contouring on the human body to feel comfortable. Recent advanced studies on these nanomaterials show that they are promising materials for effective antibacterial and antifungal agents against a variety of microbes. They also promise to provide advanced technology for biomedical applications that can be used to destroy several types of malignant cells in the human body. Moreover, they can be used as antibacterial agents in the human body. This chapter briefly discusses the cost-effective approach to organically synthesizing ZnO nanomaterials. Moreover, these ideas can be developed to characterize these materials as biomaterials to perform easily upscaled in biomedical applications.
Synthetic organic chemists have a wide range of reagents for the alterationof functional groups in organic compounds and the choice of usage is a continuouschallenge especially in the total synthesis of complex molecules. Oxidizing andreducing agents play a vital role in the total synthesis of natural and syntheticmolecules having biological importance. In this chapter, we emphasize the recentdevelopment of oxidizing and reducing agents in organic chemistry and theirimportance in the field of synthesis. Heterogeneous nanocatalysts also emerged aspowerful catalysts employed in oxidation and reduction and are studied. Definitely,oxidation-reduction in organic synthesis is an odyssey and it has ample associationwith stereoselectivity, synthetic methods, catalysis, and green chemistry.
Background: Sulfur and nitrogen heterocyclic systems, especially benzothiazine derivatives, play a vital role in the search for newer drugs due to a significant scientific interest owing to their broad range of synthetic values, various routes, and pharmacological properties. It is known that benzothiazines are divided into five units: 1,2-, 2,1-, 1,3-, 3,1-, and 1,4-benzothiazines. Incorporating two moieties (benzo and thiazine) increases the biological activity of both, and thus their values synthesize new heteropolycyclic systems. Considering their diverse roles in the biological area and synthesis chemistry, huge effects have been found in developing novel and efficient methodologies to synthesize various benzothiazine moieties with different substitutions. Methods: The present chapter comprises an inclusive vision of new and straightforward synthetic strategies to afford benzothiazine and related systems. This chapter covers various reactions for synthesizing benzothiazines, such as alkylation, acylation, aroylation, halogenation, elimination, rearrangement, ring enlargement, reduction, and oxidation. Besides, it also includes other reactions, like cyclization, addition, condensation, cyclocondensation, metal/acid-catalyzed, hydrolysis, aminolysis, hydrazinolysis, complexation, and enantio/regioselective. Moreover, many benzothiazines have been evaluated for their therapeutic activity. Result: The synthesis and chemical reactions of benzothiazines derivatives have been reported. The preparation approaches of some compounds have been found to involve many steps, and others one-pot, resulting in good to excellent yields. Also, many synthesized compounds have shown medicinal properties, such as aldose reductase,anti-inflammatory, analgesic, antimicrobial, antibacterial, antifungal, anticancer, antiviral, antioxidant, herbicidal, and anticarcinogenic, anti-tubercular, antianthelmintic, and antitumor probes. Conclusion: The chapter covers various methods to synthesize benzothiazines and their derivatives, thereby displaying their biological activities.
This chapter presents an outline of chemical reactions performed while utilizing microwave irradiation. The improvement in economic strategies has taken cognizance and acknowledgment of environment-friendly and cost-effective procedures having the most negligible impact on the environment. Compared to other methods, microwave-assisted methods proved to be more favorable substitutes for conventional laboratory heating systems; many chemical reactions have been accomplished, refining prevailing procedures with practical conclusions than the reactions proceeded under the conventional heating system. Reactions executed via catalysis in an aqueous medium enhanced the eco-friendly procedures, and the reactions executed via catalysis in fluid medium enhanced environmental conventions. In this chapter, we will discuss microwave-assisted catalytic approaches, which have been used for the preparation of various heterocyclic compounds, preparation of peptides, urea and coordination polymers having carboxyl group, and various other chemical reactions. The focus of this work is to highlight the recent advances in the field of Microwave-assisted organic reactions like oxidation, reduction, coupling, functionalization, heterocyclic compounds synthesis, multi-component reactions, and nucleophilic substitutions in water.
Olefins are molecules containing double bonds and are an active functional class. They have the potential to react easily due to the pi bonds in their structures. Therefore, olefins themselves form a biologically active class. In addition, they are pioneer molecules in obtaining different derivatives over many reaction types in organic chemistry. The presence of double bonds brings along geometric isomers (e.g., cis, trans, E, Z). The biological activities of olefins differ in geometric isomers. Therefore, stereoselectivity is important for the synthesis of olefins. In stereoselective olefin synthesis, the control is in the hands of the synthetic organic chemist. Stereoselectivity can be controlled with a correct and practical method. In this study, i) geometric isomers ii) biological activities and iii) stereoselective synthesis of olefins are focused.
Diaminomaleonitrile (DAMN) is a tetramer of hydrogen cyanide that has been used as the source of purine bases such as adenine. In the literature, DAMN seems to be an essential element used to synthesize various N-heterocyclic compounds. Numerous pharmaceutical and industrial applications have been described for DAMN derived compounds. Among these compounds are five and six-membered N-heterocyclic rings, and since their emergence, DAMN has been extensively investigated as an inexpensive and readily available reagent in synthetic and complex chemistry applications, including those that produce dyes and pigments. As a rich nitrogen source, DAMN occupies an important position in synthetic heterocyclic chemistry. Various synthetic methodologies and diverse heterocyclic structures have been produced and approved across a broad array of industrial fields. This chapter covers five and six-membered rings obtained directly from DAMN.
The peptidomimetic-based design and synthesis of HIV-1 protease and other entry inhibitors are generally oriented to block the viral receptor functionalities in the host cells. Most of the drugs classified under HIV-1 protease inhibitors are primarily optimized through substrate-based design strategies. The peptidomimetic drugs present in the market are non-hydrolyzable by the catalytic aspartic acid residues, an indispensable approach still used in designing potential pharmacophores for protease inhibitors. Thus, a variety of amino acid-containing hybrid small molecules are tested against the HIV-1 protease enzyme by incorporating essential fragments required to block protease functionalities. However, the appearance of mutations in HIV polyproteins is a key parameter to be seriously considered while designing peptidomimetics. Hence, comprehensive knowledge regarding HIV peptidomimetic/medicinal chemistry along with optimization strategy and organic synthesis awareness is critical in the current scenario. The present chapter is aimed to provide in-depth literature on medicinally optimized HIV-1 protease inhibitors, Tat TAR RNA blockers with their synthesis, and later it is expanded to the peptidomimetics (entry inhibitors) involved in the envelope glycoprotein (gp120/gp41) and capsid inhibitors. Furthermore, the knowledge-based classification of HIV-1 protease inhibitors, anti-dimer agents, Tat-TAR RNA blockers, and entry inhibitors, along with their synthetic procedures, would serve as a single model template for scientific as well as academic research towards the development of anti-HIV peptidomimetics.
The multicomponent reactions (MCRs) are vital for producing structurally varied molecular objects. Multicomponent reactions (MCRs) contain three or more synthetic stages and are carried out without isolation of any intermediate, thus requiring mild reaction conditions. They are eco-friendly and cost-effective, have a short reaction time, produce higher yields, and require raw materials. The use of microwave irradiation in green organic synthesis sustains some of the aims of “green and sustainable chemistry.” It offers several benefits over the conventional approach in reducing time, reaction rates, selectivity, product yields, etc. Consequently, the preparation of various heterocycles using a one-pot multicomponent method combined with the application of microwave irradiation is one of the best areas amongst synthetic chemistry. The present study illustrates an overview of recent progress on microwave irradiated, one-pot multicomponent synthesis of heterocycles.
<div>In March 1920, Professor Hermann Staudinger coined the term</div><div>“macromolecules” to explain the physicochemical behavior of different synthetic and</div><div>natural polymers. Far from the skepticism of the scientific community, other</div><div>researchers, such as Wallace Carothers, were able to explain not only the synthesis but</div><div>also the chemical nature of synthetic polymers by considering Staudinger´s ideas. The</div><div>Nobel Prize awarded to Staudinger in 1953 is one of the milestones of a new era in</div><div>which polymers and polymer science would certainly change the world. In this review,</div><div>the historical evolution of polymer chemistry and that of different synthetic methods to</div><div>produce polymers with well-defined molecular architectures are discussed. Different</div><div>synthetic methods are reviewed, from classical (ionic, condensation, and coordination)</div><div>to recent ones (reversible activation/deactivation using nitroxides, transfer agents or</div><div>metal complexes, conducting polymers, and meta thesis polymerization). This review is</div><div>expected to be of interest not only to those involved in polymer science but also to</div><div>others interested in the development of synthetic chemistry.</div>
The Amino Acid-derived Ionic Liquids (AAILs), as green biodegradable catalysts, gained special attention in recent years due to their alignment with green chemistry's important rules. They could be prepared via easy techniques. Ohno and coworkers synthesized amino acid-derived ILs for the first time. AAILs could play multiple roles as solvents and/or excellent promoters with high catalytic activity and also as chiral additives. The special advantages of AAILs usage are i) elevation of the product yields, ii) excellent chemo and/or stereo-selectivity, iii) short reaction times, iv) simple work-up procedures, v) diminishing or prevention of by-products formation, vi) mild reaction conditions, and vii) recoverability and reusability within several cycles without noticeable activity loss. The synthesis of pharmaceutically-active heterocycles is interesting in organic chemistry and medicinal fields. The multi-activity characteristics of AAILs make them interesting candidates for promoting different classes of MCRs to prepare heterocyclic compounds. In the book chapter, the applications of various AAILs (alone or as a part of core-shell structures) will be discussed for the synthesis of heterocycles with a glance at nano and green chemistry. The content of the chapter has been divided into two main parts, which are a) the applications of AAILs as catalysts and/or solvents in the synthesis of heterocycles, and b) employing the bionanocomposites that included AAILs as catalysts in the synthesis of heterocycles. According to the reports, they played a key role in obtaining different libraries of heterocycles, which could potentially be active drugs.
In the past, no one believed that polymers could prove to be effective Light- Emitting Diodes (LEDs). Very few research groups understood that the polymer light displayed semiconducting and electrical properties. However, it has been observed that the polymer LEDs can be used in many larger display arrays as they show mechanical flexibility and can be processed easily. The different polymers can be synthesised using reactive organic compounds, called monomers, which consist of a minimum of two functional groups. In this review, the researchers described a synthesis route for many organic monomers which can be converted to form LEDs. They have detailed the development of the polymers right from their inception. Furthermore, this review described the major mechanism related to light emission and all relevant problems associated with colour tuning. After investigating the polymer LEDs, the researchers noted that various light colours could be emitted efficiently, with uniformity and brightness. The colour of this emitted light was dependent on the band gap of π-π transition, which seem to be the function of the structure of the polymer. Hence, any modification could affect the band gap and the colour that was emitted. For developing efficient PLEDs, many factors were considered, like stable radiative transitions for the singlet excitons, balance of electrons and holes and light extraction. It was seen that the fabrication of phosphorescence emitters using the triplet-triplet energy transfer approach was an effective strategy for obtaining a high-efficiency luminescence. This review also highlighted the main routes for the fabrication and processing of the devices.
<div>In the last few decades, there is a constant demand for novel bioactive</div><div>compounds in all areas of pharmacy and medicine, thus increasing the demands for</div><div>their design and synthesis. Quinolines, quinazolines and quinazolinones, highly</div><div>bioactive heterocyclic compounds with a nitrogen core, have been employed in many</div><div>important drugs nowadays. Their synthesis often includes an enormous amounts of</div><div>different hazardous organic solvents, catalysts, as well as energy consumption. In the</div><div>last two decades, there is a growing interest in the application of different green</div><div>chemistry methods in different research areas, including synthesis. This chapter</div><div>describes their application in the synthesis of the above mentioned compounds.</div><div>Microwave-assisted, ultrasound-assisted, mechanochemical synthesis in the</div><div>combination with solvent-free synthesis and synthesis in deep eutectic solvents (DESs)</div><div>and ionic liquids (ILs) of quinolines, quinazolines and quinazolinones is described. All</div><div>mentioned green chemistry methods are gaining promising environmental and</div><div>economic benefits and are being a subject of many research these days.</div>
