Journal articles: 'Heterocyclic chemistry ; Heterocyclic compounds'

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Luna, Isadora Silva, Rayssa Marques Duarte da Cruz, Ryldene Marques Duarte da Cruz, Rodrigo Santos Aquino de Araújo, and Francisco Jaime Bezerra Mendonça-Junior. "1,4-Dithiane-2,5-diol: A Versatile Synthon for the Synthesis of Sulfur-containing Heterocycles." Current Organic Synthesis 15, no. 8 (December 17, 2018): 1026–42. http://dx.doi.org/10.2174/1570179415666180821154551.

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Background: 1,4-Dithiane-2,5-diol (1,4-DTD) is the stable dimer of α-mercapto acetaldehyde. This commercially available ambidentade compound is characterized as having in its chemical structure one group that acts as an electrophile and another that acts as a nucleophile, this permits its use as versatile and efficient synthon in synthetic heterocycle procedures. Objective: The aim of this review is to present synthetic applications of 1,4-DTD in heterocyclic chemistry and their applicability to the synthesis of bioactive compounds. Conclusion: Gewald reactions to obtain C-4 and C-5 unsubstituted 2-amino-thiophene derivatives; sulfa- Michael/Henry and sulfa-Michael/aldol sequences to obtain polysubstituted tetrahydrothiophenes, and other heterocyclic reactions that allow synthesizing several functionalized sulfur-containing heterocycles such as thiazolidines, oxathiazinoles and thiazoles are presented and discussed. The use of such heterocyclics in subsequent reactions allows obtaining various bioactive compounds including the antiretroviral lamivudine which is one of the examples presented in this review.

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Yadav, Shailendra, Sushma Singh, and Chitrasen Gupta. "A CONCISE OVERVIEW ON HETEROCYCLIC COMPOUNDS EXHIBITING PESTICIDAL ACTIVITIES." International Journal of Advanced Research 9, no. 08 (August 31, 2021): 989–1004. http://dx.doi.org/10.21474/ijar01/13352.

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Heterocyclic compounds are numerous and diverse group of organic compounds. Heterocycles are abundantly found in nature and express various physiological properties. Heterocycles are intricately linked to all aspects of life. There are many heterocyclic compounds currently known, and the number is constantly rising owing to extensive synthetic development and their applications. Heterocyclic compounds are used significantly in a number of areas, including biochemistry and medicinal chemistry, and some others. They are predominantly synthesized in agrochemical and pharmaceutical industries due to their potential biological activities. This review article focuses on recently synthesized heterocyclic compounds and their different pesticidal activities such as antifungal, antibacterial, antiviral, nematocidal, insecticidal, acaricidal, and herbicidal.

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Adak, Laksmikanta, and Tubai Ghosh. "Recent Progress in Iron-Catalyzed Reactions Towards the Synthesis of Bioactive Five- and Six-Membered Heterocycles." Current Organic Chemistry 24, no. 22 (December 18, 2020): 2634–64. http://dx.doi.org/10.2174/1385272824999200714102103.

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Heterocyclic compounds are the largely diverse organic molecules and find prevalent applications in the fine chemical industry, medicinal chemistry and agricultural science. They are also among the most commonly bearing frameworks in numerous drugs and pharmaceutical substances. Therefore, the development of convenient, efficient and environmentally benign methods to produce various types of heterocyclic compounds is an attractive area of research. For the synthesis and functionalization of heterocycles, enormous achievements have been attributed over the past decades. Recently, ironcatalyzed reactions have accomplished a noteworthy development in the synthesis of heterocycles. This review highlights some remarkable achievements in the iron-catalyzed synthesis of heterocyclic compounds published in the last five years.

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Shaikh, Ansar R., Mazahar Farooqui, R. H. Satpute, and Syed Abed. "Overview on Nitrogen containing compounds and their assessment based on ‘International Regulatory Standards’." Journal of Drug Delivery and Therapeutics 8, no. 6-s (December 21, 2018): 424–28. http://dx.doi.org/10.22270/jddt.v8i6-s.2156.

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Heterocyclic compounds have a role in most fields of sciences such as medicinal chemistry, biochemistry also another area of sciences. More than 90% of new drugscontain heterocycles and the interface between chemistry and biology, at which so much new scientific insight, discovery and application is taking place is crossed by heterocyclic compounds. Compounds derived from heterocyclic rings in pharmacy, medicine, agriculture, plastic, polymer and other fields.Most active heterocycles that have shown considerable biological actions as antifungal, anti-inflammatory, antibacterial, anticonvulsant, antiallergic, herbicidal, anticancer activity. There is always a strong need for new and efficient processes in synthesizing of new Heterocycles.Alum have been used as a novel catalyst in the synthesis of Schiff’s bases. Synthesized Schiff’s bases are free from use of ICH class 1 and Class 2 solvents and also free from structural alerts genotoxic impurities. This review highlights on various aspects of heterocyclic compounds with its biological activity & regulatory assessment based on the ‘International Regulatory Standards’. Keywords: Heterocycles. Nitrogen containing compounds Biological activity, History, Regulatory assessment, International Regulatory Standards

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Sharma, Praveen Kumar, Andleeb Amin, and M. Kumar. "Synthetic Methods of Medicinally Important Heterocycles-thiazines: A Review." Open Medicinal Chemistry Journal 14, no. 1 (September 14, 2020): 71–82. http://dx.doi.org/10.2174/1874104502014010071.

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Heterocyclic compounds containing N and S atoms have unique properties so that they can be used as potential reactive materials in pharmacokinetic systems. In medicinal chemistry, the therapeutic applications of nitrogen sulphur heterocycles are well known. Especially, Thiazines attract the attention of chemists due to their great bioactive behavior. The present study is a review of the work carried out by the research community for the synthesis of novel, effective, medicinally important heterocyclic compounds-thiazines.

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Monier, Mohamed, Doaa Abdel-Latif, Ahmed El-Mekabaty, Başak D. Mert, and Khaled M. Elattar. "Advances in the Chemistry of 6-6 Bicyclic Systems: Chemistry of Pyrido[3,4- d]pyrimidines." Current Organic Synthesis 16, no. 6 (November 26, 2019): 812–54. http://dx.doi.org/10.2174/1570179416666190704113647.

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The aim of this work is to discuss the chemistry of pyrido[3,4-d]pyrimidines as one of the most important heterocyclic compounds with remarkable synthetic, biological and medical applications. In this overview, the chemistry of heterocyclic compounds incorporated the pyrido[3,4-d]pyrimidine scaffold as demonstrated by chemical reactions and different preparation processes. The anticipated compounds were synthesized from pyridine or pyrimidine compounds and a description of the reactivity of substituents attached to ring carbon and nitrogen atoms is discussed. On the other hand, the synthesis and reactions of fused heterocycles incorporated pyrido[3,4-d]pyrimidine scaffold is described. The diamine analogs included pyrido[3,4-d]pyrimidine core were reported as tyrosine kinase inhibitors. The chemical reactions of certain unexpected and chemically substantial compounds have been discussed.

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Sajida. Munadi. Th.AL-Suraify and Mohammed Abdul-Mounther Othman. "Synthesis and study of spectrally diagnosed heterocyclic compound." International Journal of Research in Pharmaceutical Sciences 11, SPL4 (December 21, 2020): 2613–22. http://dx.doi.org/10.26452/ijrps.v11ispl4.4527.

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In general terms, medicinal chemistry manages the revelation & plan of recent remedial synthetic concoctions & its uses as meds. Throughout the most recent couple of decades, mixes bearing heterocyclic cores have gotten considerably more consideration of the scientific expert, because of their expansive chemo remedial exercises, for example, calming, anthelmintic, hostile to tubercular, against parasitic & hostile to microbial exercises. Furthermore, Heterocycles & medicines are both interred related, the human is totally dependent on drugs & most of the drugs are derived from heterocyclic compounds. Hetero cycles & their derivatives have been excited regards chemist mainly due to broad-spectrum chemical & pharmacological activities. Most of the heterocyclic compounds are naturally occurs & playing the important role of metabolism regards cells of living. There has been a bigger count of pharmacologically attracted compounds of heterocyclic, several of which have been under continues clinical utilization. This paper presented a detailed study of synthesis which is spectrally detected Heterocyclic compounds, in results described the antibacterial activity of (e)-s-4-(is nicotinamide)-5-(phenoxymethyl)-4h-1, 2, 4-triazol-3-yl 3-(substituted phenyl) prop-2- enethioate. (7a-7f) and antifungal activity of (e)-s-4-(isonicotinamido)-5-(phenoxymethyl)-4h-1, 2, 4-triazol-3-yl 3-(substituted phenyl) prop-2-enethioate. (7a-7f), antitubercular activity of against mycobacterium tuberculosis h37rv presented the scope of this paper.

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Harith M. Al-ajely. "Synthesis and pharmaceutical applications of Oxazine compounds derived from Pyronic, Salicylic, Antharanilic acids and Phenols." International Journal of Science and Research Archive 2, no. 2 (May 30, 2021): 074–86. http://dx.doi.org/10.30574/ijsra.2021.2.2.0250.

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It is well known from FDA reports that More than 75% of the heterocyclic compounds are drugs and 90 of heterocyclic compounds are cancer drugs. The nitrogen-based heterocycles occupy an exclusive position as a valuable source of therapeutic agents in medicinal chemistry. Most drugs approved by the FDA and currently available in the market are nitrogen-containing heterocyclic moieties, More over heterocyclic compounds are important class of organic chemistry due to their widely spread in nature. Also there are many route for their action and many mechanistic pathways for their preparation and different metabolic actions. This comes from the easily building or removal of any functional group within the molecules. Changing just on group cause to change the metabolic pathway of the drug action and site of attack of the desired target accordingly. This great characteristic value make them much more important in drug discovery programs of many researchers and also encouraged us and drew attentions of other researchers to develop new ways for their synthesis. As a result different pharmacological and medical applications. Oxazie compounds are sub branch of heterocyclic compounds. These compounds having two hetero atoms, Oxygen and nitrogen within their structures make them much more important toward therapeutic studies. We are here in our investigation will focus on the methodologies and the therapeutic action of the titled compounds as well as other various applications.

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Slivka, Mikhailo, and Mikhailo Onysko. "The Use of Electrophilic Cyclization for the Preparation of Condensed Heterocycles." Synthesis 53, no. 19 (May 19, 2021): 3497–512. http://dx.doi.org/10.1055/s-0040-1706036.

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AbstractCondensed heterocycles are well-known for their excellent biological effects and they are undeniably important compounds in organic chemistry. Electrophilic cyclization reactions are widely used for the synthesis of mono-heterocyclic compounds. This review highlights the utility of electrophilic cyclization reactions as an effective generic tool for the synthesis of various condensed heterocycles containing functional groups that are able to undergo further chemical transformations, such as nucleophilic substitution, elimination, re-cyclization, cleavage, etc. This review describes the reactions of unsaturated derivatives of different heterocycles with various electrophilic agents (halogens, arylsulfanyl chlorides, mineral acids) resulting in annulation of an additional partially saturated heterocycle. The electrophilic reaction conditions, plausible mechanisms and the use of such transformations in organic synthesis are also discussed. The review mainly focuses on research published since 2002 in order to establish the current state of the art in this area. 1 Introduction2 Electrophilic Cyclization Pathways Involving a Nitrogen Nucleophilic Center3 Electrophilic Cyclization Pathways Involving a Chalcogen Nucleophilic Center3.1 Sulfur Centers3.2 Oxygen Centers3.3 Selenium Centers4 Strategies and Mechanisms5 Conclusion

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10

Francke, Robert. "Recent advances in the electrochemical construction of heterocycles." Beilstein Journal of Organic Chemistry 10 (December 3, 2014): 2858–73. http://dx.doi.org/10.3762/bjoc.10.303.

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Due to the fact that the major portion of pharmaceuticals and agrochemicals contains heterocyclic units and since the overall number of commercially used heterocyclic compounds is steadily growing, heterocyclic chemistry remains in the focus of the synthetic community. Enormous efforts have been made in the last decades in order to render the production of such compounds more selective and efficient. However, most of the conventional methods for the construction of heterocyclic cores still involve the use of strong acids or bases, the operation at elevated temperatures and/or the use of expensive catalysts and reagents. In this regard, electrosynthesis can provide a milder and more environmentally benign alternative. In fact, numerous examples for the electrochemical construction of heterocycles have been reported in recent years. These cases demonstrate that ring formation can be achieved efficiently under ambient conditions without the use of additional reagents. In order to account for the recent developments in this field, a selection of representative reactions is presented and discussed in this review.

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Haji, Mohammad. "Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates." Beilstein Journal of Organic Chemistry 12 (June 21, 2016): 1269–301. http://dx.doi.org/10.3762/bjoc.12.121.

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Multicomponent reactions (MCRs) are one of the most important processes for the preparation of highly functionalized organic compounds in modern synthetic chemistry. As shown in this review, they play an important role in organophosphorus chemistry where phosphorus reagents are used as substrates for the synthesis of a wide range of phosphorylated heterocycles. In this article, an overview about multicomponent reactions used for the synthesis of heterocyclic compounds bearing a phosphonate group on the ring is given.

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Zhu, Yannan, and You Huang. "Organocatalyzed [3+3] Annulations for the Construction of Heterocycles." Synthesis 52, no. 08 (February 5, 2020): 1181–202. http://dx.doi.org/10.1055/s-0039-1690810.

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Six-membered heterocyclic systems are widely distributed in many natural products and pharmaceuticals, and the construction of highly functionalized six-membered heterocyclic compounds is an important topic in modern organic synthesis. Organocatalyzed [3+3] annulations represents an important method for assembling a substantial variety of six-membered cycles that contain one or more heteroatoms. This review describes the development of organocatalyzed [3+3] annulations for the synthesis of six-membered heterocycles, including organocatalysis using secondary amines, tertiary amines, phosphines, chiral phosphoric acids and N-heterocyclic carbenes.1 Introduction2 Secondary Amine Catalyzed [3+3] Annulations2.1 Synthesis of Nitrogen Heterocycles2.2 Synthesis of Oxygen Heterocycles2.3 Synthesis of Sulfur Heterocycles3 Tertiary Amine Catalyzed [3+3] Annulations3.1 Catalysis through Multiple Hydrogen-Bonding Interactions3.2 Catalysis of Tertiary Amines as Lewis Bases4 Phosphine-Catalyzed [3+3] Annulations4.1 Synthesis of Nitrogen Heterocycles4.2 Synthesis of Oxygen Heterocycles4.3 Synthesis of Heterocycles Containing Two or More Heteroatoms5 Chiral Phosphoric Acid Catalyzed [3+3] Annulations5.1 Synthesis of Nitrogen Heterocycles5.2 Synthesis of Heterocycles Containing Two or More Heteroatoms6 N-Heterocyclic Carbene Catalyzed [3+3] Annulations6.1 Synthesis of Nitrogen Heterocycles6.2 Synthesis of Oxygen Heterocycles6.3 Synthesis of Heterocycles Containing Two or More Heteroatoms7 Conclusion and Outlook

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Kaur, Navjeet, Neha Ahlawat, Yamini Verma, Pooja Grewal, and Pranshu Bhardwaj. "A Review of Ruthenium-catalyzed C-N Bond Formation Reactions for the Synthesis of Five-membered N-heterocycles." Current Organic Chemistry 23, no. 18 (November 26, 2019): 1901–44. http://dx.doi.org/10.2174/1385272823666191021104118.

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The field of heterocyclic chemistry has been revolutionized using transition metal catalysts in recent years. Various research groups have focused on the development of general protocols to achieve better functional group compatibilities and greater levels of molecular complexity under mild reaction conditions, using easily available starting substrates. The methodologies used earlier for their synthesis were less approachable to organic chemists because of their high cost, highly specified instrumentation and inconvenient methods. For both stereoselective and regioselective synthesis of five-membered nitrogen- containing heterocycles, cyclic reactions that are Ru-catalyzed have known to be very efficient. These methods have many advantages as compared to alternative pathways involved in the synthesis of heterocyclic compounds. In this review article, we concentrated on the synthesis of nitrogen-containing five-membered heterocycles in the presence of a ruthenium catalyst. This review mostly covers the literature published during the period from 1977-2019.

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Su, Biyun, Yifan Hou, Li Wang, Xiaoteng Li, Dandan Pan, Tingyu Yan, Ao Zhang, Faida Paison, and Liqing Ding. "The Syntheses, Characterization and Crystal Structures of a Series of Heterocyclic β-Diketones and Their Isoxazole Compounds." Current Organic Synthesis 16, no. 8 (January 20, 2020): 1174–84. http://dx.doi.org/10.2174/1570179416666191022113022.

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Background: In the field of coordination chemistry, the introduction of heterocyclic substituents into the structure of β-diketone enables ligand to produce multiple coordination sites. The adoption of small steric oxime group into the structure of heterocyclic β-diketone by Schiff-base condensation will further increase coordination sites and facilitate the generation of polynuclear structures. Objective: A series of β-diketones (2a-2c) containing different heterocycles such as pyridine, thiophene and furan and their corresponding isoxazole compounds (3a-3c) were synthesized. Materials and Methods: The Claisen condensations were investigated in a solvent-free rheological phase system at room temperature to obtain heterocyclic β-diketones 2a-2c, which further reacted with hydroxylamine hydrochloride to obtain heterocyclic isoxazoles 3a-3c. All these compounds were well characterized by EA, IR, 1H NMR and X-ray crystal diffraction to confirm the structures. Synthetic mechanisms of compounds and the effects of different heterocycles on reactivity were discussed deeply. Result: 1H NMR indicated that these β-diketones do not exist as a total diketonic form but an equilibration between diketone and enol forms in CDCl3 solvent, in which the enol form accounts for 98.0% in 2a, 94.3% in 2b, 95.5% in 2c. While the crystal structures of 2a-2c showed that the reaction allows to isolate diketones in solid state. Crystal structures of 3a-3c showed that the neutral β-ketone oximes resonate and cyclize to form the target heterocyclic isoxazoles. Conclusion: SN1 nucleophilic substitution mechanism of Claisen ketoester condensation was proposed for the syntheses of 2a-2c, and SN1 single molecule nucleophilic substitution reaction mechanism was put forward for 3a-3c.

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Pyne, Stephen. "Preface." Pure and Applied Chemistry 80, no. 4 (January 1, 2008): iv. http://dx.doi.org/10.1351/pac20088004iv.

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This issue of Pure and Applied Chemistry comprises 12 papers from some of the speakers at the 21st International Congress for Heterocyclic Chemistry, which was held at the University of New South Wales, Sydney, Australia from 15-20 July 2007. The topics of these papers cover some of the major themes of the conference, including natural products synthesis (as highlighted by the presentation of K. C. Nicolaou during his ISHC Senior Award in Heterocyclic Chemistry lecture on the synthesis of complex natural products and further demonstrated by contributions by Profs. Banwell, Bates, Sodeoka, Naito, Vogel, and Pyne); new methods for the synthesis of heterocycles based on metal-catalyzed reactions (Profs. Ma and Mase); and new catalysts for asymmetric synthesis based on chiral heterocyclic ligands (Prof. Nishiyama). Papers on the synthesis of heterocyclic compounds using the borono-Mannich reaction (Prof. Hutton) and green chemistry methods (Prof. Varma) are also included.I would like to thank all contributors for their timely efforts and the editorial staff for their help.Stephen PyneConference Editor

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Sparr, Christof, and Christian Fischer. "Configurationally Stable Atropisomeric Acridinium Fluorophores." Synlett 29, no. 16 (August 3, 2018): 2176–80. http://dx.doi.org/10.1055/s-0037-1610233.

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Arylated heterocyclic fluorophores are particularly useful scaffolds for numerous applications, such as bioimaging or synthetic photochemistry. While variation of the substitution pattern at the heterocycle and aryl groups allows dye modulation, the bond rotational barriers are also strongly affected. Unsymmetrically substituted ring systems of rotationally restricted arylated heterocycles therefore lead to configurationally stable atropisomeric fluorophores. Herein, we describe these characteristics by determining the properties and configurational stability of atropisomeric, tri-ortho-substituted naphthyl-acridinium fluorophores. A significant barrier to rotation of >120 kJ mol–1 was measured, which renders these dyes and related compounds distinct atropisomers with stereoisomer-specific properties over a broad temperature range.

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Murarka, Sandip, and Andrey Antonchick. "Metal-Catalyzed Oxidative Coupling of Ketones and Ketone Enolates." Synthesis 50, no. 11 (May 3, 2018): 2150–62. http://dx.doi.org/10.1055/s-0037-1609715.

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Recent years have witnessed a significant advancement in the field of radical oxidative coupling of ketones towards the synthesis of highly useful synthetic building blocks, such as 1,4-dicarbonyl compounds, and biologically important heterocyclic and carbocyclic compounds. Besides oxidative homo- and cross-coupling of enolates, other powerful methods involving direct C(sp3)–H functionalizations of ketones have emerged towards the synthesis of 1,4-dicarbonyl compounds. Moreover, direct α-C–H functionalization of ketones has also allowed an efficient access to carbocycles and heterocycles. This review summarizes all these developments made since 2008 in the field of metal-catalyzed/promoted radical-mediated functionalization of ketones at the α-position.1 Introduction2 Synthesis of 1,4-Dicarbonyl Compounds3 Synthesis of Heterocyclic Scaffolds4 Synthesis of Carbocyclic Scaffolds5 Conclusion

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Bąchor, Urszula, and Marcin Mączyński. "Selected β2-, β3- and β2,3-Amino Acid Heterocyclic Derivatives and Their Biological Perspective." Molecules 26, no. 2 (January 15, 2021): 438. http://dx.doi.org/10.3390/molecules26020438.

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Heterocyclic moieties, especially five and six-membered rings containing nitrogen, oxygen or sulfur atoms, are broadly distributed in nature. Among them, synthetic and natural alike are pharmacologically active compounds and have always been at the forefront of attention due to their pharmacological properties. Heterocycles can be divided into different groups based on the presence of characteristic structural motifs. The presence of β-amino acid and heterocyclic core in one compound is very interesting; additionally, it very often plays a vital role in their biological activity. Usually, such compounds are not considered to be chemicals containing a β-amino acid motif; however, considering them as this class of compounds may open new routes of their preparation and application as new drug precursors or even drugs. The possibility of their application as nonproteinogenic amino acid residues in peptide or peptide derivatives synthesis to prepare a new class of compounds is also promising. This review highlights the actual state of knowledge about β-amino acid moiety-containing heterocycles presenting antiviral, anti-inflammatory, antibacterial compounds, anaplastic lymphoma kinase (ALK) inhibitors, as well as agonist and antagonists of the receptors.

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Deng, Yongming, Qing-Qing Cheng, and Michael Doyle. "Asymmetric [3+3] Cycloaddition for Heterocycle Synthesis." Synlett 28, no. 14 (July 5, 2017): 1695–706. http://dx.doi.org/10.1055/s-0036-1588453.

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Asymmetric syntheses of six-membered ring heterocycles are important research targets not only in synthetic organic chemistry but also in pharmaceuticals. The [3+3]-cycloaddition methodology is a complementary strategy to [4+2] cycloaddition for the synthesis of heterocyclic compounds. Recent progress in [3+3]-cycloaddition processes provide powerful asymmetric methodologies for the construction of six-membered ring heterocycles with one to three heteroatoms in the ring. In this account, synthetic efforts during the past five years toward the synthesis of enantioenriched six-membered ring heterocycles through asymmetric [3+3] cycloaddition are reported. Asymmetric organocatalysis uses chiral amines, thioureas, phosphoric acids, or NHC catalysis to achieve high enantiocontrol. Transition-metal catalysts used as chiral Lewis acids to activate a dipolar species is an alternative approach. The most recent advance, chiral transition-metal-catalyzed reactions of enoldiazo compounds, has contributed toward the versatile and highly selective synthesis of six-membered heterocyclic compounds.1 Introduction2 Asymmetric Formal [3+3]-Cycloaddition Reactions by Organocatalysis2.1 By Amino-Catalysis2.2 By N-Heterocyclic Carbenes2.3 By Bifunctional Tertiary Amine-thioureas2.4 By Chiral Phosphoric Acids3 Asymmetric Formal [3+3]-Cycloaddition Reactions by Transition-Metal Catalysis3.1 Copper Catalysis3.2 Other Transition-Metal Catalysis4 Asymmetric [3+3]-Cycloaddition Reactions of Enoldiazo Compounds4.1 Asymmetric [3+3]-Cycloaddition Reactions of Nitrones with Electrophilic Metallo-enolcarbene Intermediates4.2 Dearomatization in Asymmetric [3+3]-Cycloaddition Reactions of Enoldiazoacetates4.3 Asymmetric Stepwise [3+3]-Cycloaddition Reaction of Enoldiazoacetates with Hydrazones5 Summary and Outlook

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Gaonkar, Santosh L., Vignesh U. Nagaraj, and Swarnagowri Nayak. "A Review on Current Synthetic Strategies of Oxazines." Mini-Reviews in Organic Chemistry 16, no. 1 (November 19, 2018): 43–58. http://dx.doi.org/10.2174/1570193x15666180531092843.

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In the past three decades, the heterocyclic oxazine cores have been intensely concerned. Oxazine derivatives are promising vital heterocyclic motifs. They are eminent for their synthetic potential and extensive biological properties. Oxazines are versatile intermediates for the synthesis of a variety of heterocycles and bifunctional compounds. Researchers have reported several synthetic approaches for the preparation of oxazines. This review emphasises the recent approaches for the synthesis of oxazine derivatives.

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Drapak, І. V. "In silico screening of drug-like molecules for the treatment of cardiovascular diseases on the basis of five-membered privileged heterocycles." Farmatsevtychnyi zhurnal, no. 4 (September 10, 2019): 61–72. http://dx.doi.org/10.32352/0367-3057.4.19.07.

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Among various heterocyclic systems, the derivatives of five-membered heterocycles are of special interest. Most of the above mentioned heterocycles are treatred as so-called privileged structures in modern medicinal chemistry. In silico screening among five-membered heterocycles of molecules for the treatment of cardiovascular diseases is actual. The aim of the work was the search for synthetic drug-like molecules based on functionalized five-membered heterocycles and related heterocyclic systems as an element of the theoretical platform for rational design of compounds acting on the cardiovascular system, and prediction of their possible mechanism of action. The objects of the study were derivatives of uncondensed and condensed five-membered heterocycles. In the work, in silico approaches were applied using the programs: Hyper-Chem, PASS, AutoDock, PROTOX. Based on the previous studies, focused sub-libraries of small synthetic drug-like molecules based on functionalized five-membered heterocycles and related heterocyclic systems have been selected. The compounds were divided on 12 groups. The optimization of the compound structures, the drug-like parameters calculation were carried out. The activity prediction, the acute toxicity level and docking studies to probable bio-targets which are related with cardiovascular drug mechanism of action have been carried out. It was shown that thiazole and thiadiazole based compounds possessed the highest calculated affinity levels to selected bio-targets. This is consistent with PASS-based prediction data. Diverse functionalized derivatives of five-membered heterocycles (thiazole, thiazolidine, thiadiazole, pyrazole, thiophene, triazole) and related fused heterocycles have been grouped in focused sub-libraries of compounds. it has been established that thiazole and thiadiazole based compounds are promising objects for directed synthesis and further modification as potential cardiovascular agents based on the prediction of biological activity, the calculation of affinity to potent bio-targets, and the prediction of the drug-like features and acute toxicity level. The prognostic values of the parameters of the above mentioned groups of compounds may be used as the element of theoretical platform for the search and de novo design of potential drugs for the treatment of cardiovascular diseases.

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Chen, Zhangpei, Lingxin Meng, Zhiqiang Ding, and Jianshe Hu. "Construction of Versatile N-Heterocycles from in situ Generated 1,2-Diaza-1,3-dienes." Current Organic Chemistry 23, no. 2 (April 23, 2019): 164–87. http://dx.doi.org/10.2174/1385272823666190227162840.

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N-Heterocyclic architectures are omnipresent in many bioactive natural products, synthetic drugs, and materials science, thus have evoked a vast research interest of academic, as well as industrial chemists. Recently, several efficient methods have been developed for the preparation of various nitrogen-containing compounds with in situ generated 1,2-diaza-1,3-dienes from the easily available precursors including α -haloketohydrazones, α-hydroxyl ketohydrazones, thiadiazole dioxides or their analogues, and other simple hydrazones. These methods are considered powerful tools in the synthesis of five-, six- and seven-membered ring heterocyclic compounds with good to excellent levels of conversions and selectivities. This review mainly summarizes recent advances on the chemistry of construction of versatile N-heterocycles from in situ generated 1,2-diaza-1,3- dienes and presents an extensive summary of the application scopes and limitations of the corresponding cyclization reactions. Moreover, enantioselective approaches are also covered.

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Hanusek, Jiří, and Vladimír Macháček. "Intramolecular base-catalyzed reactions involving interaction between benzene nitro groups and ortho carbon chains." Collection of Czechoslovak Chemical Communications 74, no. 5 (2009): 811–33. http://dx.doi.org/10.1135/cccc2008216.

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The review is focused on the understanding of processes involving chemical interaction between benzene nitro group and ortho carbon chain containing heteroatom (N, O, S) adjacent to the ring. In most cases these compounds undergo base-catalyzed cyclization to give heteroaromatic N-oxides that can be subsequently transformed to related heterocycles under the same conditions. However, in some cases, depending on substitution of the benzene ring, side chain or the base used, the formation of other compounds – both heterocyclic and non-heterocyclic such as nitroso and azoxy compounds, spiro Meisenheimer adducts – is observed. Review with 31 references.

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Foldesi, Tamas, Balazs Volk, and Matyas Milen. "A Review of 2,3-Benzodiazepine-related Compounds: Diazepines and 1,2,5- Triazepines Fused with Five-membered Nitrogen Heterocycles." Current Organic Synthesis 15, no. 6 (August 29, 2018): 729–54. http://dx.doi.org/10.2174/1570179415666180601101856.

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Background: 2,3-Benzodiazepines represent an important class of biologically active compounds, some members of this family have reached the human clinical stage. With formal bioisosteric replacement of the benzene ring to five-membered nitrogen heterocycles, several new diazepine and 1,2,5-triazepine derivatives have been synthesized in the past 30 years. Objective: Investigations in the field of heterocyclic chemistry is very important, because there could be several new medicines among the newly synthesized heterocyclic ring systems, which could be used against several diseases which have no remedy yet, for example some types of cancer. The research on antibacterial compounds is also an important field because of spreading of multiresistant pathogens. This review aims to summarize the literature of certain 2,3-benzodiazepine analogues. Conclusion: After a brief historical introduction, various ring systems containing a 2,3-diazepine or a 1,2,5- triazepine ring condensed with five-membered nitrogen heterocycles are disclosed. First, pyrrole-fused compounds are introduced, followed by indole and carbazole derivatives. After that, diverse ring systems containing an imidazole ring are presented. The review is closed with the chemistry of some interesting triazole and tetrazole derivatives. Many of these compounds bear significant biological efficacy.

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Mir, Reyaz Hassan, Roohi Mohi-ud-din, Taha Umair Wani, Mohammad Ovais Dar, Abdul Jaleel Shah, Bashir Lone, Chawla Pooja, and Mubashir Hussain Masoodi. "Indole: A Privileged Heterocyclic Moiety in the Management of Cancer." Current Organic Chemistry 25, no. 6 (March 26, 2021): 724–36. http://dx.doi.org/10.2174/1385272825666210208142108.

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Heterocyclic are a class of compounds that are intricately entwined into life processes. Almost more than 90% of marketed drugs carry heterocycles. Synthetic chemistry, in turn, allocates a cornucopia of heterocycles. Among the heterocycles, indole, a bicyclic structure consisting of a six-membered benzene ring fused to a five-membered pyrrole ring with numerous pharmacophores that generate a library of various lead molecules. Due to its profound pharmacological profile, indole got wider attention around the globe to explore it fully in the interest of mankind. The current review covers recent advancements on indole in the design of various anti-cancer agents acting by targeting various enzymes or receptors, including (HDACs), sirtuins, PIM kinases, DNA topoisomerases, and σ receptors.

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Li, Chongyang, Yongli Huang, Chang Q. Sun, and Lei Zhang. "Acidic Stabilization of the Dual-Aromatic Heterocyclic Anions." Catalysts 11, no. 7 (June 24, 2021): 766. http://dx.doi.org/10.3390/catal11070766.

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Recently, we discovered that the delocalization of nitrogen lone-pair electrons (NLPEs) in five-membered nitrogen heterocycles created a second σ-aromaticity in addition to the prototypical π-aromaticity. Such dual-aromatic compounds, such as the pentazole anion, were proved to have distinct chemistry in comparison to traditional π-aromatics, such as benzene, and were surprisingly unstable, susceptible to electrophilic attack, and relatively difficult to obtain. The dual-aromatics are basic in nature, but prefer not to be protonated when confronting more than three hydronium/ammonium ions, which violates common sense understanding of acid−base neutralization for a reason that is unclear. Here, we carried out 63 test simulations to explore the stability and reactivity of three basic heterocycle anions (pentazole anion N5¯, tetrazole anion N4C1H1¯, and 1,2,4-triazole anion N3C2H2¯) in four types of solvents (acidic ions, H3O+ and NH4+, polar organics, THF, and neutral organics, benzene) with different acidities and concentrations. By quantum mechanical calculations of the electron density, atomistic structure, interatomic interactions, molecular orbital, magnetic shielding, and energetics, we confirmed the presence of dual aromaticity in the heterocyclic anions, and discovered their reactivity to be a competition between their basicity and dual aromaticity. Interestingly, when the acidic ions H3O+/NH4+ are three times more in number than the basic heterocyclic anions, the anions turn to violate acid−base neutralization and remain unprotonated, and the surrounding acidic ions start to show a significant stabilization effect on the studied heterocyclic anions. This work brings new knowledge to nitrogen aromatics and the finding is expected to be adaptable for other pnictogen five-membered ring systems.

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Orzeszko, Barbara, Tomasz Świtaj, Anna B. Jakubowska-Mućka, Witold Lasek, Andrzej Orzeszko, and Zygmunt Kazimierczuk. "Tumor Necrosis Factor-α Production-Enhancing Properties of Novel Adamantylalkylthio Derivatives of Some Heterocyclic Compounds." Zeitschrift für Naturforschung B 60, no. 4 (April 1, 2005): 471–75. http://dx.doi.org/10.1515/znb-2005-0419.

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Certain adamantylated heterocycles were previously shown to enhance the secretion of tumor necrosis factor alpha (TNF-α) by murine melanoma cells that have been transduced with the gene for human TNF-α and constitutively expressed this cytokine. The stimulatory potency of those compounds depended, among other factors, on the structure of the linker between the adamantyl residue and the heterocyclic core. In the present study, a series of (1-adamantyl)alkylsulfanyl derivatives of heterocyclic compounds was prepared by alkylation of the corresponding thioheterocyles. Of the novel adamantylalkylthio compounds tested in the aforementioned cell line, 2-(2-adamantan-1-ylethylsulfanyl)- 4-methyl-pyrimidine was found to be the most active

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Pang, Shaofeng, Yujing Zhang, Qiong Su, Fangfang Liu, Xin Xie, Zhiying Duan, Feng Zhou, Ping Zhang, and Yanbin Wang. "Superhydrophobic nickel/carbon core–shell nanocomposites for the hydrogen transfer reactions of nitrobenzene and N-heterocycles." Green Chemistry 22, no. 6 (2020): 1996–2010. http://dx.doi.org/10.1039/c9gc04358f.

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In this work, catalytic hydrogen transfer as an effective, green, convenient and economical strategy is for the first time used to synthesize anilines and N-heterocyclic aromatic compounds from nitrobenzene and N-heterocycles in one step.

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Sharad K. Awate, Suresh V. Patil, Ravindra S. Dhivare, and Renukacharya G. Khanapure. "Microwave-Assisted Synthesis, Characterization and Antimicrobial Potencies of N-Substituted Iminothiazodin-4-One Derivatives." International Journal of Research in Pharmaceutical Sciences 11, no. 1 (January 18, 2020): 589–95. http://dx.doi.org/10.26452/ijrps.v11i1.1861.

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The biggest and most multifaceted class of organic compounds includes heterocyclic compounds. Currently, several heterocyclic compounds are identified, and persistently gratefulness to tremendous synthetic work and synthetic usefulness, the number is increasing exponentially. In most fields of science, including medicinal, pharmaceutical, and agro-chemistry, heterocyclic compounds have a function, and biochemistry is also another area. In this research article, the green approach is administered for achieving the nitrogen, oxygen and sulphur centered five-membered heterocyclic derivatives. By taking the whole thing into account of hetero-chemistry, the moderately effective analog for gram-positive and gram-negative strains was shown for the five-membered heterocyclic compound series of N-substituted iminothiazodine-4-one and N-(benzylideneamino)thiazol-4(5H). The compound 6b showed very much active potency in accordance with the type standard drug the 6c compound against gram-positive Bacillus subtilis bacteria compared to the standard drugs and 6b indicated very active potency against the gram-negative Escherichia coli bacterial strain. The 5a and 6a compounds showed very strong activity against the fungal strain of Candida albicans and 6b or 6c were more active and highly potent than the standard drugs against Aspergillus niger species. In the view of this research, drive states that all the synthesized compounds might be used for the development for further heterocyclic entities.

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Giubellina, Nicola, Wim Aelterman, and Norbert De Kimpe. "Use of 3-halo-1-azaallylic anions in heterocyclic chemistry." Pure and Applied Chemistry 75, no. 10 (January 1, 2003): 1433–42. http://dx.doi.org/10.1351/pac200375101433.

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The synthetic potential of lithio 3-halo-1-azaallylic anions as building blocks in organic chemistry and especially in heterocyclic chemistry will be highlighted by the synthesis of functionalized imines, obtained after reaction of 3-halo-1-azaallylic anions with het- eroatom-substituted electrophiles. Thus, the latter generated functionalized imines are suitable building blocks for the synthesis of a whole range of heterocycles and physiologically active compounds, including agrochemicals and pharmaceuticals. 3-Halo-1-azaallylic anions were used in the synthesis of N-alkyl-3,3-dichloroazetidines, 2,3-disubstituted pyrroles, piperidines, 2-substituted pyridines, 2-alkoxytetrahydrofurans,etc., from which a large range of useful and interesting chemicals can be produced, e.g., 2-azetines and 9-alkyl- 2-phenyl-3a-beta,4,6,7,8,9,9a-beta,9b-beta-octahydro-1H-pyrrolo [3,4,h]quinoline-1,3-diones. The utility of the present methodology is demonstrated by the synthesis of the pheromone (S)-manicone, the sulfur-containing flavor compound 2-[(methylthio)methyl ]-2-butenal, and some agrochemical and pharmaceutical compounds.

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Hassan, Alaa A., Stefan Bräse, Ashraf A. Aly, and Hendawy N. Tawfeek. "Chemistry of Substituted Thiazinanes and Their Derivatives." Molecules 25, no. 23 (November 28, 2020): 5610. http://dx.doi.org/10.3390/molecules25235610.

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Thiazinanes and its isomeric forms represent one of the most important heterocyclic compounds, and their derivatives represented a highly potent drug in disease treatment such as, 1,1-dioxido-1,2-thiazinan-1,6-naphthyridine, which has been shown to have anti-HIV activity by a mechanism that should work as anti-AIDS treatment, while (Z)-methyl 3-(naphthalen-1-ylimino)- 2-thia-4-azaspiro[5 5]undecane-4-carbodithioate showed analgesic activity, cephradine was used as antibiotic and chlormezanone was utilized as anticoagulants. All publications were interested in the chemistry of thiazine (partially or fully unsaturated heterocyclic six-membered ring containing nitrogen and sulfur), but no one was dealing with thiazinane itself which encouraged us to shed new light on these interesting heterocycles. This review was focused on the synthetic approaches of thiazinane derivatives and their chemical reactivity.

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Chambers, Richard D., Ali Khalil, Christopher B. Murray, Graham Sandford, Andrei S. Batsanov, and Judith A. K. Howard. "Polyhalogenated heterocyclic compounds." Journal of Fluorine Chemistry 126, no. 7 (July 2005): 1002–8. http://dx.doi.org/10.1016/j.jfluchem.2005.01.018.

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Randić, Milan, Sonja Nikolić, and Nenad Trinajstić. "Aromaticity in heterocyclic molecules containing divalent sulfur." Collection of Czechoslovak Chemical Communications 53, no. 9 (1988): 2023–54. http://dx.doi.org/10.1135/cccc19882023.

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The conjugated circuits model is applied to heterocycles containing divalent sulfur. A novel parametrization is introduced for 4n + 2 and 4n conjugated circuits containing a single sulfur atom. The relative aromatic stabilities of a number of heterocyclic systems containing divalent sulfur are studied. Comparison is made whenever possible with earlier reported resonance energies of these compounds, obtained by using Huckel MO and SCF π-MO models, and appropriate reference structures. Special attention is given to positional isomers. An explanation of the differences amongst such isomers is given.

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Aly, Ashraf A., Alaa A. Hassan, Maysa M. Makhlouf, and Stefan Bräse. "Chemistry and Biological Activities of 1,2,4-Triazolethiones—Antiviral and Anti-Infective Drugs." Molecules 25, no. 13 (July 3, 2020): 3036. http://dx.doi.org/10.3390/molecules25133036.

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Mercapto-substituted 1,2,4-triazoles are very interesting compounds as they play an important role in chemopreventive and chemotherapeutic effects on cancer. In recent decades, literature has been enriched with sulfur- and nitrogen-containing heterocycles which are used as a basic nucleus of different heterocyclic compounds with various biological applications in medicine and also occupy a huge part of natural products. Therefore, we shed, herein, more light on the synthesis of this interesting class and its application as a biologically active moiety. They might also be suitable as antiviral and anti-infective drugs.

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Zapol’skii, Viktor A., Ursula Bilitewski, Sören R. Kupiec, Isabell Ramming, and Dieter E. Kaufmann. "Polyhalonitrobutadienes as Versatile Building Blocks for the Biotargeted Synthesis of Substituted N-Heterocyclic Compounds." Molecules 25, no. 12 (June 21, 2020): 2863. http://dx.doi.org/10.3390/molecules25122863.

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Substituted nitrogen heterocycles are structural key units in many important pharmaceuticals. A new synthetic approach towards heterocyclic compounds displaying antibacterial activity against Staphylococcus aureus or cytotoxic activity has been developed. The selective synthesis of a series of 64 new N-heterocycles from the three nitrobutadienes 2-nitroperchloro-1,3-butadiene, 4-bromotetrachloro-2-nitro-1,3-butadiene and (Z)-1,1,4-trichloro-2,4-dinitrobuta-1,3-diene proved feasible. Their reactions with N-, O- and S-nucleophiles provide rapid access to push-pull substituted benzoxazolines, benzimidazolines, imidazolidines, thiazolidinones, pyrazoles, pyrimidines, pyridopyrimidines, benzoquinolines, isothiazoles, dihydroisoxazoles, and thiophenes with unique substitution patterns. Antibacterial activities of 64 synthesized compounds were examined. Additionally, seven compounds (thiazolidinone, nitropyrimidine, indole, pyridopyrimidine, and thiophene derivatives) exhibited a significant cytotoxicity with IC50-values from 1.05 to 20.1 µM. In conclusion, it was demonstrated that polyhalonitrobutadienes have an interesting potential as structural backbones for a variety of highly functionalized, pharmaceutically active heterocycles.

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Geisenberger, Josef, Jürgen Erbe, Jürgen Heidrich, Ulrich Nagela, and Wolfgang Beck. "Pseudohalogenometallverbindungen, LXV [1] Synthese von Tetrazolen und Triazolen über die 1,3-dipolare Cycloaddition an die Azid-Liganden von polymeren Cobalt(III)-und Palladium(II)-Komplexen. Darstellung und Struktur von 5-TrichlormethyItetrazol / Pseudohalogeno Metal Compounds, LXV [1] Synthesis of Tetrazoles and Triazoles via 1,3-Dipolar Cycloaddition to the Azido Ligands of Polymerie Cobalt(III) and Palladium(II) Complexes. Synthesis and Structure of 5-Trichloromethyltetrazole." Zeitschrift für Naturforschung B 42, no. 1 (January 1, 1987): 55–64. http://dx.doi.org/10.1515/znb-1987-0112.

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Abstract The cycloaddition of nitriles and of dimethylacetylenedicarboxylate to the azide ligand of polymeric Schiff Base cobalt(III) and phosphine palladium(II) complexes gives the corresponding tetrazolate and triazolate complexes from which the heterocycles could be cleaved by hydrogen chloride. Usually the yields are low; if the heterocycle is soluble in ether or sublimable, yields up to 30% have been obtained. Using this method the hitherto unknown 5-trichlormethyltetrazole could be prepared which was characterized by an X-ray structural analysis. Similarly, the cyclo-addition of azido(tetraphenylporphinato)cobalt(III) with nitriles, cyclohexylisocyanide and MeO2CC≡CCO2 Me affords the corresponding complexes with heterocyclic ligands. The prepa-ration of tetraphenylporphyrinato(tricyanmethanido)cobalt(III), (TPP)CoN=CC(CN)2 , is reported.

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Kassam, Karim, and John Warkentin. "Reactions of dialkoxycarbenes with tethered triple bonds to form heterocyclic compounds." Canadian Journal of Chemistry 75, no. 2 (February 1, 1997): 120–28. http://dx.doi.org/10.1139/v97-016.

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Dialkoxycarbenes with a tethered triple bond, generated from the corresponding oxadiazolines, undergo an intramolecular cyclization with the tethered alkyne moiety to give 3,3-dialkoxyvinylcarbene/1,3-dipole intermediates. The regioselectivity of the carbene cyclization is highly dependent upon the nature of the alkyne substituent. In the cases where an exocyclic vinylcarbene is generated, the vinylcarbene intermediate can undergo a synthetically useful [3 + 2] cycloaddition with either an appropriate olefin or an alkyne. This approach allows the rapid construction of some interesting heterocyclic ring systems. Keywords: carbene, dialkoxycarbene, vinylogous dialkoxycarbene, heterocycle.

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Gevorgyan, Vladimir. "Chemistry of heterocyclic compounds: a Renaissance." Chemistry of Heterocyclic Compounds 48, no. 1 (April 2012): 1. http://dx.doi.org/10.1007/s10593-012-0958-6.

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de Andrade, Vitor, and Marcio de Mattos. "N-Halo Reagents: Modern Synthetic Approaches for Heterocyclic Synthesis." Synthesis 51, no. 09 (March 27, 2019): 1841–70. http://dx.doi.org/10.1055/s-0037-1611746.

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Heterocyclic chemistry is an essential frontier in science and a source of novel biologically active compounds. The development of innovative synthetic methodologies that allows access to different heterocyclic rings is of critical interest to the scientific community. This review will focus on recent applications of N-halo compounds (e.g., N-halosuccinimides, trihaloisocyanuric acids, N-halosulfonamides, etc.) in heterocyclic construction via electrophilic cyclization, asymmetric halocyclization, oxidative cyclization, and radical processes.1 Introduction2 N-Halo Reagent Mediated Heterocyclic Construction and Functionalization2.1 Electrophilic Halocyclizations2.1.1 Asymmetric Halocyclizations2.2 Radical Halocyclizations2.3 Oxidative Halocyclizations2.4 Miscellaneous Halocyclization Reactions3 Summary and Outlook

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Kiyani, Hamzeh. "Recent Advances in Three-Component Cyclocondensation of Dimedone with Aldehydes and Malononitrile for Construction of Tetrahydrobenzo[b]pyrans Using Organocatalysts." Current Organic Synthesis 15, no. 8 (December 17, 2018): 1043–72. http://dx.doi.org/10.2174/1570179415666181031124459.

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Background: The majority of naturally occurring compounds, pharmaceuticals, and drug-candidate molecules possess heterocyclic scaffolds. In this context, tetrahydobenzo[b]pyrans are of considerable importance. In the line with the synthesis of these valuable heterocyclic compounds, the researchers tried to synthesize these molecules using different organocatalysts. The development of new strategies for three-component condensation of dimedone, various aldehydes and malononitrile for construction of tetrahydrobenzo[b]pyrans is of particular interest to organic chemists and pharmacologists. Objective: In this review, three-component catalyzed synthesis of tetrahydrobenzo[b]pyran compounds is introduced, focusing on the developments in the use of organocatalysts. Organocatalytic approaches were investigated for the synthesis of tetrahydrobenzo[b]pyrans. This contribution covers the literature concerning the synthesis of heterocycles referred to, in recent times. Conclusion: This review article is associated with the study of the three-component synthesis of tetrahydrobenzo[b]pyrans using organocatalysts. This review also provides an insight into the importance of these heterocycles. In the vast majority of these reactions, water and water-ethanol system have been used as green solvent media for implementation of them. The use of green solvents, the development of less toxic and promising reagents/catalysts as well as the design of inexpensive and reliable approaches are some of the principles of green chemistry, and most of the methods are benefited from them. Tetrahydrobenzo[b]pyrans and organocatalysts open avenue ofnew horizons. The recyclability of the many of these organocatalysts offers an additional merit for the use of these catalysts in 3-CR of aldehydes, dimedone, and malononitrile reactions.

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Li, Jin-Heng, De-Lie An, and Jing-Hao Qin. "Recent Advances in Cycloaddition Reactions with Alkynes to Construct Heterocycles." Synthesis 52, no. 24 (October 13, 2020): 3818–36. http://dx.doi.org/10.1055/s-0040-1707355.

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Heterocyclic compounds, especially N-heterocycles and O-heterocycles, are prominent structural motifs present in numerous natural products and medically and/or economically important compounds. This review aims to describe the development of transition-metal-catalyzed cycloaddition reactions of functionalized m-atom partners with alkynes to access a wide range of five-, six-, and seven-membered heterocycles, that is functionalized N-heterocycles and O-heterocycles such as azepines, isoquinolines, isocoumarins, spiroheterocycles, indoles, furans, and pyrroles, in a selectively controlled manner with an emphasis on scope and limitations and with a discussion of the mechanisms.1 Introduction2 Intermolecular Cycloaddition To Construct Azepine Derivatives2.1 [5+2] Cycloaddition2.2 [3+2+2] Cycloaddition2.3 [3+2]/[5+2] Cycloaddition3 Intermolecular [4+2] Cycloaddition To Construct Isoquinolines or Isocoumarins4 Intermolecular [3+2] Cycloaddition To Construct Spiroheterocyclic Compounds, Indoles, Furans, and Pyrroles5 Summary and Outlook

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Chanderiya, Aayushi, Gowhar A. Naikoo, Ratnesh Das, Israr U. Hassan, Sushil K. Kashaw, and Sadanand Pandey. "Recent Advances in Metal Nanoparticles for the Synthesis of N-Containing Heterocyclic Compounds." Asian Journal of Chemistry 33, no. 5 (2021): 949–55. http://dx.doi.org/10.14233/ajchem.2021.23140.

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Heterocyclic compounds are indispensable organic structures because of their promising potential applications in medicinal, pharmaceutical and other related fields of chemistry. Exploring these heterocyclic compounds by evaluating metal nanoparticles as efficient nanocatalysts have attracted the researchers over the past decades, due to their stability, recyclability, reusability rather than conventional catalysts. Most of the nano-catalyzed organic reactions are taking place in benign and under green conditions. In this mini-review, we have documented synthesis of some of the recent N-containing heterocyclic compounds by utilizing advanced nanoparticles as effective catalysts. It has been concluded that exercising these nanocatalysts for the synthesis of N-containing heterocyclic compounds not only enhanced the yield of the product but has extensively increased the selectivity of the desired products via greener approach.

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Lang, Damanpreet K., Rajwinder Kaur, Rashmi Arora, Balraj Saini, and Sandeep Arora. "Nitrogen-Containing Heterocycles as Anticancer Agents: An Overview." Anti-Cancer Agents in Medicinal Chemistry 20, no. 18 (November 23, 2020): 2150–68. http://dx.doi.org/10.2174/1871520620666200705214917.

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Background: Cancer is spreading all over the world, and it is becoming the leading cause of major deaths. Today’s most difficult task for every researcher is to invent a new drug that can treat cancer with minimal side effects. Many factors, including pollution, modern lifestyle and food habits, exposure to oncogenic agents or radiations, enhanced industrialization, etc. can cause cancer. Treatment of cancer is done by various methods that include chemotherapy, radiotherapy, surgery and immunotherapy in combination or singly along with kinase inhibitors. Most of the anti-cancer drugs use the concept of kinase inhibition. Objective: The number of drugs being used in chemotherapy has heterocycles as their basic structure in spite of various side effects. Medicinal chemists are focusing on nitrogen-containing heterocyclic compounds like pyrrole, pyrrolidine, pyridine, imidazole, pyrimidines, pyrazole, indole, quinoline, oxadiazole, azole, benzimidazole, etc. as the key building blocks to develop active biological compounds. The aim of this study is to attempt to compile a dataset of nitrogen-containing heterocyclic anti-cancer drugs. Methods: We adopted a structural search on notorious journal publication websites and electronic databases such as Bentham Science, Science Direct, PubMed, Scopus, USFDA, etc. for the collection of peer-reviewed research and review articles for the present review. The quality papers were retrieved, studied, categorized into different sections, analyzed and used for article writing. Conclusion: As per FDA databases, nitrogen-based heterocycles in the drug design are almost 60% of unique small-molecule drugs. Some of the nitrogen-containing heterocyclic anti-cancer drugs are Axitinib, Bosutinib, Cediranib, Dasatanib (Sprycel®), Erlotinib (Tarceva®), Gefitinib (Iressa®), Imatinib (Gleevec®), Lapatinib (Tykerb ®), Linifanib, Sorafenib (Nexavar®), Sunitinib (Sutent®), Tivozanib, etc. In the present review, we shall focus on the overview of nitrogen-containing heterocyclic active compounds as anti-cancer agents.

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Neha, Ashish Ranjan Dwivedi, Rakesh Kumar, and Vinod Kumar. "Recent Synthetic Strategies for Monocyclic Azole Nucleus and Its Role in Drug Discovery and Development." Current Organic Synthesis 15, no. 3 (April 27, 2018): 321–40. http://dx.doi.org/10.2174/1570179414666171013154337.

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Background: In recent years, the development and diversification of heterocyclic compounds has become central to the discovery of bioactive compounds with novel or improved pharmacological properties. In particular, N-containing heterocycles are proved to be promising leads and drug candidates, and received huge attention of the medicinal chemists. Objective: Many drugs especially antibiotics are becoming obsolete due to the development of multidrug resistance. Moreover, toxicity and other side effects of some drugs necessitated the quest for safer and more potent drug candidates. The current review article described biological potential of various monocyclic azoles. Recent developments in the synthesis of azole derivatives have been also reviewed. Conclusion: The presence of N-heterocyclic rings can influence the pharmacokinetics, pharmacodynamics, pKa and bioavailability profile of the drug molecules. Compounds containing monocyclic azole rings showed various biological activities and number of molecules are in clinical practice. A number of important leads and potential drug candidates containing azole nucleus are in advance stages of drug developments. Thus, simple, atom economic and more efficient synthetic strategies are desired for the synthesis of new libraries of the compounds.

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Kibbel, Hans Ulrich, Hartmut Blödorn, and Peter Hansen. "Heterocyclic Compounds from Thiooxamidehydrazides." Phosphorus, Sulfur, and Silicon and the Related Elements 74, no. 1-4 (January 1993): 453. http://dx.doi.org/10.1080/10426509308038160.

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Sbei, Najoua, Anna V. Listratova, Alexander A. Titov, and Leonid G. Voskressensky. "Recent Advances in Electrochemistry for the Synthesis of N-Heterocycles." Synthesis 51, no. 12 (May 7, 2019): 2455–73. http://dx.doi.org/10.1055/s-0037-1611797.

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The construction of N-heterocyclic rings represents a very important and fast-developing area of organic synthesis. In this context, electrochemistry has emerged as a mild solution for generating in situ the required electrophilic substrates, bases and nucleophiles derived from low-level and extremely stable reagents, the further application of which makes some heterocycles more accessible. In this review, we have covered the recent advances in the electrochemical synthesis of five- and six-membered N-heterocyclic compounds published from 2017 to October 2018.1 Introduction2 Electrochemical Synthesis of Five-Membered N-Containing Heterocycles2.1 Pyrrolidines2.2 Imidazoles2.3 Pyrazoles2.4 Triazoles2.5 Oxazoles2.6 Indoles2.7 Thiazoless3 Electrochemical Synthesis of Six-Membered N-Containing Heterocycles3.1 Piperidines and Pyridines3.2 Quinazolinones3.3 Benzoxazines4 Conclusions

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Soni, Jay, Ayushi Sethiya, Nusrat Sahiba, Dinesh K. Agarwal, and Shikha Agarwal. "Contemporary Progress in the Synthetic Strategies of Imidazole and its Biological Activities." Current Organic Synthesis 16, no. 8 (January 20, 2020): 1078–104. http://dx.doi.org/10.2174/1570179416666191007092548.

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: Heterocyclic compounds are pervasive in many areas of life and one of the heterocycles, imidazole is a unique heterocyclic five-membered aromatic compound having two sp2 hybridized nitrogen atoms. Its integral name is 1, 3 diazole and previously, it was known as glyoxalin. This moiety has achieved a considerable place among scientists in recent years by reason of its divergent synthetic strategies and uncommon biological and pharmacological activities, for example, anti-convulsant, anti-microbial, anti-cancer, anti-inflammatory, anti-tumor, anti-viral, anti-ulcer, analgesic, etc. Due to distinct therapeutic actions, it is still an engrossed area of research. Researchers currently are inventing new greener methods to synthesize its derivatives and to improve its pharmacological activities. The purpose of this review is to study the literature that can help researchers to explore this area, its prevailing program for synthesis in environmentally friendly conditions and biological profile throughout past decades.

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Akishina, E. A., and Е. А. Dikusar. "Chemical modification of different compounds with nitrogen-containing heterocycles." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 57, no. 3 (September 5, 2021): 356–84. http://dx.doi.org/10.29235/1561-8331-2021-57-3-356-384.

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Heterocyclic compounds have an extremely important practical application, since many heterocycles are the basis of the most valuable medicinal substances, both natural (vitamins, enzymes, alkaloids, etc.) and synthetic biologically active compounds. The work mainly considers the most relevant directions for various purposes drugs search by modifying known bioactive natural, organoelement and framework compounds with 1,2-azole, oxazole, oxadiazole, thiazole, triazole, pyridine, pyrimidine heterocycles over the past 10 years. Chemical modification makes it possible to increase the water solubility of the compounds, which is important when choosing the pathways for the most rational drug introduction into the body, to reduce the toxicity of the corresponding substances, to increase the breadth of the therapeutic action, and also to give new valuable medicinal properties, thus significantly expanding their application in medicine and agriculture.

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Santos, A. Sofia, Daniel Raydan, José C. Cunha, Nuno Viduedo, Artur M. S. Silva, and M. Manuel B. Marques. "Advances in Green Catalysis for the Synthesis of Medicinally Relevant N-Heterocycles." Catalysts 11, no. 9 (September 15, 2021): 1108. http://dx.doi.org/10.3390/catal11091108.

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Abstract:

N-heterocycles, both saturated and unsaturated, are ubiquitous biologically active molecules that are extremely appealing scaffolds in drug discovery programs. Although classical synthetic methods have been developed to access many relevant N-heterocyclic scaffolds, representing well-established and reliable routes, some do not meet the needs of sustainability. In this context, several advances have been made towards the sustainable synthesis of N-heterocycles. This review focuses on the most recent examples from the last five years of catalytic synthesis of several heterocyclic compounds of medicinal relevance. Thus, the synthesis of isoindoloquinazolines, quinazolines and azaindoles, among others, are covered. The synthetic methods selected include the use of homogeneous and heterogeneous catalysts and the use of alternative and sustainable methods such as, for example, metal-catalyzed acceptorless coupling and one-pot reactions. The green aspects of the individual synthetic approaches are highlighted, and the scope of each methodology is described.

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Strekowski, Lucjan. "Biologically Relevant Heterocyclic Compounds." Molecules 9, no. 3 (February 28, 2004): 39. http://dx.doi.org/10.3390/90300039.

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Journal articles on the topic 'Heterocyclic chemistry ; Heterocyclic compounds'

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