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Chapter

Cover Organonitrogen Chemistry

Amines  

This chapter introduces the features of nitrogen. It recognises nitrogen as the most abundantly gas in the world despite its lack of reactivity. Next, the chapter highlights the flexible organic compounds which can be combined with the presence of nitrogen. It looks into neutral nitrogen, trivalent nitrogen, and common organonitrogen functional groups. The chapter also discusses the components of saturated nitrogen compounds. It highlights the importance of nitrogen in organic chemistry and the significance of organonitrogen chemistry in the evolution of life. In terms of modern life, organonitrogen chemistry is linked to natural products such as DNA, peptides, proteins, alkaloids, man-made pharmaceuticals, fibres, and dyes.

Chapter

Cover Human Physiology

The chemical constitution of the body  

This chapter describes the human body as consisting largely of four elements: oxygen, carbon, hydrogen, and nitrogen. It shows that about 70 percent of the lean body tissues is water, while the remaining 30 percent made up of organic material (i.e. molecules and minerals). The principal organic constituents of mammalian cells are the carbohydrates, fats, proteins, and nucleic acids, which are built from smaller molecules belonging to four classes of chemical compounds: sugars, fatty acids, amino acids, and nucleotides respectively. The chapter outlines the principal minerals found in tissues: calcium, phosphorus, potassium, and sodium. It gives an approximate indication of the chemical composition of the body for a young adult male, noting that there is individual variation and that the proportions of the various constituents vary between tissues and change during development.

Chapter

Cover Organonitrogen Chemistry

Amides  

This chapter discusses enamines. It explains the process of achieving enamine through regaining neutrality by losing a proton adjacent to the iminium moiety. Additionally, these compounds rarely serve as nucleophiles or bases on nitrogen. The chapter discusses the formation of enamines from amine and aldehyde or ketone. It highlights how electrophiles are required to be quite reactive as enamines are moderately nucleophilic. The chapter adds the hydrolysis of enamine which is an effort to regenerate the original secondary amine and reveal the carbonyl group. Also, it explores the tautomerism of using imines as enamines and vice versa.

Chapter

Cover Biochemistry

Nitrogen Metabolism I: Synthesis  

This chapter talks about nitrogen, which is found in a vast array of biomolecules, such as amino acids and the nitrogenous bases which are used in the synthesis of proteins and the nucleic acids. Other essential nitrogen-containing biomolecules include the porphyrins, certain membrane lipids, and a diverse group of metabolically important biomolecules that are synthesized in smaller amounts. The chapter traces nitrogen from nitrogen fixation, the process that converts inert N2 to biologically useful ammonia through the synthesis of the major nitrogen-containing biomolecules. It describes the nitrogen cycle as the biogeochemical cycle in which nitrogen atoms flow through the biosphere. Several biochemical processes convert nitrogen from one form to another.

Chapter

Cover Inorganic Chemistry

The Group 15 elements  

This chapter focuses on the Group 15 elements which exhibit a wide range of oxidation states and form many complex compounds with oxygen. The chapter presents detailed chemistry of nitrogen, phosphorus, arsenic, antimony, bismuth, and moscovium. The chapter discusses nitrogen activation, nitrides, and azides, as well as phosphides. It also describes arsenides, antimonides, and bismuthides, and looks at hydrides, halides, and oxohalides. Furthermore, the chapter considers the oxides and oxoanions of nitrogen; oxides of phosphorus, arsenic, antimony, and bismuth; and the oxoanions of phosphorus, arsenic, antimony, and bismuth. Next, it sheds light on condensed phosphates, phosphazenes, and the organometallic compounds of arsenic, antimony, and bismuth.

Chapter

Cover Bioinorganic Chemistry

Nitrogenase and nitrogen cycle enzymes  

This chapter focuses on the enzymes involved in the nitrogen cycle. One of its focal points is nitrogen fixation, or nature's way of converting nitrogen gas reductively to ammonium ions for direct use in life processes. Biological nitrogen fixation is the natural counterpart of industrial nitrogen fixation by the Haber–Bosch process. The chapter also addresses the procedural methodology by which nature cycles nitrogen between ammonia (with nitrogen in its lowest oxidation state), nitrogen gas, and nitrate (with nitrogen in its highest oxidation state), highlighting that the understanding of the versatility and differentiation by which this biochemical processing of nitrogen occurs has been a vital issue in bioinorganic chemistry in the past decades, and will be of prime interest also in the coming years. The chapter tackles nitrogenase models and model reactions and explains nitrification and denitrification. Lastly, it takes a closer look at nitric oxide.

Chapter

Cover Thrive in Biochemistry and Molecular Biology

Microbial and plant metabolism  

This chapter illustrates microbial and plant metabolism. Some important metabolic pathways are unique to microorganisms and plants. These include trapping of solar energy, and fixation of atmospheric nitrogen and carbon, so they are essential to (almost) all life. The chapter then looks at photosynthesis. Almost all the energy consumed by biological systems derives ultimately from solar energy trapped by photosynthesis carried out by green plants and photosynthetic bacteria. The chapter also considers nitrogen assimilation and ethanol production. Nitrogen fixation is carried out by some bacteria and blue-green algae (cyanobacteria) which catalyze reduction of N2 to ammonia (NH3). Meanwhile, ethanol is a highly reduced, two-carbon compound produced from glucose by some bacteria or fungi under anaerobic conditions. It is a commercially important product of fermentation by brewers' yeast, Saccharomyces cerevisiae.

Chapter

Cover Reactive Intermediates

Nitrenes  

This chapter focuses on nitrenes, which are six-electron neutral, monovalent, highly reactive nitrogen intermediates wherein the nitrogen atom has four non-bonded electrons. It describes nitrenes as monovalent short-lived species. These were first suggested as intermediates in 1891: the Lossen rearrangement. It also points out that the chemistry of nitrenes closely parallels that of carbenes in all aspects. The chapter examines the possibility of two spins states for nitrenes. These depended on whether two non-bonding electrons have their spins paired or paralleled. It explains how nitrenes obey Hund's Rule and are ground state triplets with two degenerate sp-orbitals containing a single electron. It highlights the energy difference between the singlet and triplet states. This is usually much larger for nitrenes than for carbenes.

Chapter

Cover Organonitrogen Chemistry

Compounds with NN bonds  

This chapter looks into urethanes, ureas, imides, and diimides, which encompasses the most important remaining nitrogen-containing functional groups aside from those which have N-N or N-O bonds. It highlights the importance of urethanes as readily removable N-protective groups. Additionally, the chapter discusses the synthesis and reaction of urethanes, ureas, imides, and diimides. Urethanes are significant for protecting amines, while imides are useful for preparing primary amines. Diimides are one of the best types of reagent for the coupling of carboxylic acids to amines. Finally, the chapter lists other unsaturated nitrogen-containing groups such as amidines, imidines, guanidines, and imidate esters.

Chapter

Cover Biochemistry and Molecular Biology

Nitrogen metabolism: amino acid metabolism  

This chapter refers to amino acids which are supplied in the diet from protein hydrolysis in the gut. This includes proteins in the body that are constantly degraded and resynthesized. The chapter clarifies how the body can synthesize about ten of the amino acids. The rest must be obtained from the diet, but all 20 are needed for protein synthesis. Amino acids are also used to synthesize a wide variety of other molecules. The chapter discusses amino acids in excess of immediate requirements and shows that these are deaminated as the amino nitrogen is mainly converted into urea in mammals and excreted. The carbon-hydrogen skeletons are oxidized to release energy or converted into fat or glycogen according to the metabolic controls operating at the time and the particular amino acid.

Chapter

Cover Thrive in Human Physiology

Introduction  

This chapter considers underlying molecular and cellular elements and the link between structure and function in physiology to provide an understanding of the structures within the body. It discusses the body in terms of the hierarchical nature of organization from the molecular level through to the organismal level. It also highlights the elemental composition of the vast majority of the body which is formed from carbon, oxygen, hydrogen, oxygenydrogen, carbon, and nitrogen. The chapter analyzes an individual's body weight in terms of body composition, which is accounted for by water and is found in a variety of compartments. Given that water accounts for most of an individual’s body weight, the chapter looks in depth at the forms this water takes. It explains that the water within the body has a variety of solutes dissolved in it that. These form extracellular fluid and intracellular fluid, each of which has a unique composition.

Chapter

Cover Why chemical reactions happen

Leaving groups  

This chapter explains leaving groups. It discusses the energy profile in line with leaving groups by using a diagram to emphasize its points. The chapter notes bond strength and stability as factors which are important for a good leaving group. Leaving group ability is a good guide to working out which reactions will go and which will not. The chapter highlights how some reactions do not occur despite their predicted mechanisms. It shares how relative energies of the species are vital in predicting whether reactions will go readily or not. The chapter also shows how to reverse reactions that do not take place by using ketone reacting to acyl chlorides as an example. It cites neutral nitrogen as the best leaving group.

Chapter

Cover Statistical Thermodynamics

The electronic partition function  

This chapter focuses on the electronic partition function. Atoms and molecules can achieve electronic excitation energy levels and experience a rise in energy to states above the ground electronic state. The chapter highlights that excited electronic states showcase no regular or predictable series of increasing energies. It notes that high excitation energies mean that molecules' excited electronic states remain unpopulated unless the temperature increases to several thousands of kelvins. Additionally, the chapter includes degeneracy in the equation formula as electronic states can enter into the partition function for atoms via the degeneracy of the ground electronic state. The chapter explores the singular case of nitrogen monoxide as an isolated two-state system.

Chapter

Cover Fundamentals of Plant Physiology

Assimilation of Inorganic Nutrients  

This chapter focuses on nutrient assimilation, which is the incorporation of inorganic nutrients into organic substances such as pigments, enzyme cofactors, lipids, nucleic acids, and amino acids. Assimilation of some nutrients,particularly nitrogen and sulfur, involves a complex series of biochemical reactions that are among the most energy-consuming reactions in living organisms. Assimilation of other nutrients, especially the macronutrient and micronutrient cations, involves the formation of complexes with organic compounds. The chapter outlines the primary reactions through which the major nutrients (nitrogen, sulfur, phosphate, and iron) are assimilated and discusses the organic products of these reactions. It emphasizes the physiological implications of the required energy expenditures and introduces the topic of symbiotic nitrogen fixation. Plants serve as the major conduit through which nutrients pass from slower geophysical domains into faster biological ones; the chapter thus highlights the vital role of plant nutrient assimilation in the human diet.

Book

Cover Organonitrogen Chemistry

Patrick D. Bailey and Keith M. Morgan

Organonitrogen Chemistry introduces a wealth of fascinating organic chemistry involving nitrogen. There are three main sections to the book, each being introduced by a summary of the underlying chemical principles. The main organonitrogen functional groups are covered systematically, each chapter concluding with a brief summary of the chemistry. Topics include amines, ammonium compounds, nitrogen bases, and synthesis of amines. The second part of the book covers amines, ammonium compounds, nitrogen bases, and synthesis of amines. Finally, the text looks at compounds with N-N bounds, oximes, N -oxides, nitroso compounds and, nitro compounds.

Chapter

Cover Oxidation and Reduction in Organic Synthesis

Reduction of carbon–heteroatom double and triple bonds  

This chapter explores the reduction of carbon–heteroatom double and triple bonds. There are many functional groups based on multiple bonds between carbon and either oxygen or nitrogen. The chapter demonstrates some of the corresponding reduction reactions of these functional groups. It begins by looking at the reduction of carbon–nitrogen π-bonds. Nitriles contain a strong triple bond between carbon and nitrogen. In terms of reactivity, nitriles are susceptible to nucleophilic attack and therefore reduction of these groups is easily effected by 'hydride' reducing agents. The chapter then considers the reduction of carbon–oxygen π-bonds. The reduction of aldehydes to primary alcohols and ketones to secondary alcohols is normally easy to accomplish using sodium borohydride or lithium aluminium hydride.

Chapter

Cover Organic Chemistry

Aromatic heterocycles 1: reactions  

This chapter investigates the reactions of aromatic heterocycles. Benzene is aromatic because it has six electrons in a cyclic conjugated system. Most organic compounds belong to the class of aromatic heterocycles, and they number among them some of the most significant compounds for human beings. The chapter begins by considering how aromaticity survives when parts of benzene’s ring are replaced by nitrogen atoms. How can we insert a heteroatom into the ring and retain aromaticity? What kind of atom is needed? If we want to replace one of the carbon atoms of benzene with a heteroatom, we need an atom that can be trigonal to keep the flat hexagonal ring, and that has a p orbital to keep the six delocalized electrons. Nitrogen fits all of these requirements. This is what happens if we replace a CH group in benzene with a nitrogen atom. The chapter then looks at reactions of five-membered heterocycles, as well as benzo-fused heterocycles.

Chapter

Cover Making the Transition to University Chemistry

Amines and Amino Acids  

This chapter describes the mechanisms of amines and amino acids. It also notes the two common naming systems of amines, which are known to be one class of organic compounds with nitrogen atoms. Amines are classified in terms of their general formulas, alkyl group, and hydrogen atoms attached to the nitrogen atom. The Gabriel synthesis is a method of successfully making a primary amine. Amino acids have two function groups: an amino group and a carboxylic acid group. Amino acids also polymerize to construct polypeptides. The chapter discusses the effects of pH and zwitterions as well.

Chapter

Cover Cell Signalling

Reactive oxygen species, reactive nitrogen species and redox signalling  

This chapter explains our current understanding of how reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated and perceived, and how they propagate their messages. It argues that the main components involved here include those used in phosphorylation and cyclic nucleotides. The chapter also explains that ROS and RNS are in control of a host of cellular functions. It emphasizes that ROS and RNS are now known to be important as signals in many biological systems, including prokaryotes, animals, and plants. Lastly, the chapter considers redox signalling and molecular mechanisms of hydrogen peroxide signalling.

Chapter

Cover Organic Chemistry

Acidity, basicity, and pK a  

This chapter assesses acidity, basicity, and pK a. An acid is a species having a tendency to lose a proton, while a base is a species having a tendency to accept a proton. The measure of acidity or basicity is called pK a; the value of pK a tells us how acidic (or not) a given hydrogen atom in a compound is. Knowing about pK a is useful because many reactions proceed through protonation or deprotonation of one of the reactants, and it is obviously useful to know what strength acid or base is needed. The chapter then considers nitrogen compounds as acids and bases, and looks at carbon acids, the development of the drug cimetidine, and Lewis acids and bases.