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Patonay, T. Dehaen, W.

Heterocyclic chemistry: Not just what you do but how you think about it

Ed , Bakulev, V. Publishing With Us.

Book Authors Journal Authors. Topics in Heterocyclic Chemistry. The series Topics in Heterocyclic Chemistry presents critical reviews on present and future trends in the research of heterocyclic compounds. Overall the scope is to cover topics dealing with all areas within heterocyclic chemistry, both experimental and theoretical, of interest to the general heterocyclic chemistry community.

The series consists of topic related volumes edited by renowned editors with contributions of experts in the field.

General aspects of heterocyclic compounds

Share this. Titles in this series. Refine Search. Content Type. Release Date. Showing 56 results. Ed This volume is devoted to compounds in which the spiro centre is part of a pyranoid or furanoid or an iminosugar ring. The chapters contributed deal with methodological …. Ed This volume describes the recent developments in the free-radical mediated synthesis and elaboration of heterocycles. The first chapter, dealing with radical cascade processes ….

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Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass cellulose and related materials , and many natural and synthetic dyes. Although heterocyclic chemical compounds may be inorganic compounds or organic compounds, most contain at least one carbon. While atoms that are neither carbon nor hydrogen are normally referred to in organic chemistry as heteroatoms, this is usually in comparison to the all-carbon backbone. But this does not prevent a compound such as borazine which has no carbon atoms from being labelled "heterocyclic". Heterocyclic compounds can be usefully classified based on their electronic structure.

The saturated heterocycles behave like the acyclic derivatives.

HETEROCYCLIC COMPOUNDS- 1

Thus, piperidine and tetrahydrofuran are conventional amines and ethers, with modified steric profiles. Therefore, the study of heterocyclic chemistry focuses especially on unsaturated derivatives, and the preponderance of work and applications involves unstrained 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of heterocycles are fused to benzene rings, which for pyridine, thiophene, pyrrole, and furan are quinoline, benzothiophene, indole, and benzofuran, respectively.

Fusion of two benzene rings gives rise to a third large family of compounds, respectively the acridine, dibenzothiophene, carbazole, and dibenzofuran. The unsaturated rings can be classified according to the participation of the heteroatom in the conjugated system, pi system.

Heterocycles with three atoms in the ring are higher in energy and more reactive because of ring strain. Those containing one heteroatom are, in general, stable. Those with two heteroatoms are more likely to occur as reactive intermediates. The 5-membered ring compounds containing two heteroatoms, at least one of which is nitrogen, are collectively called the azoles. Thiazoles and isothiazoles contain a sulfur and a nitrogen atom in the ring. Dithiolanes have two sulfur atoms. A large group of 5-membered ring compounds with three or more heteroatoms also exists.

Heterocyclic compound

One example is the class of dithiazoles , which contain two sulfur atoms and one nitrogen atoms. The hypothetical compound with six nitrogen heteroatoms would be hexazine. With 7-membered rings, the heteroatom must be able to provide an empty pi orbital e. Compounds with one heteroatom include:. Heterocyclic rings systems that are formally derived by fusion with other rings, either carbocyclic or heterocyclic, have a variety of common and systematic names. For example, with the benzo-fused unsaturated nitrogen heterocycles, pyrrole provides indole or isoindole depending on the orientation.

The pyridine analog is quinoline or isoquinoline. For azepine, benzazepine is the preferred name.

Likewise, the compounds with two benzene rings fused to the central heterocycle are carbazole , acridine , and dibenzoazepine. Thienothiophene are the fusion of two thiophene rings. Phosphaphenalenes are a tricyclic phosphorus-containing heterocyclic system derived from the carbocycle phenalene. The history of heterocyclic chemistry began in the s, in step with the development of organic chemistry.

Some noteworthy developments: [6] Brugnatelli isolates alloxan from uric acid Dobereiner produces furfural a furan by treating starch with sulfuric acid Runge obtains pyrrole "fiery oil" by dry distillation of bones Friedlander synthesizes indigo dye , allowing synthetic chemistry to displace a large agricultural industry Treibs isolates chlorophyl derivatives from crude oil, explaining the biological origin of petroleum.

Heterocyclic compounds are pervasive in many areas of life sciences and technology. From Wikipedia, the free encyclopedia.