Structure and Nomenclature of Acid Derivatives

Structure and Nomenclature of Acid Derivatives 982 21-3 Physical Properties of Carboxylic Acid Derivatives 988 21-4 Spectroscopy of Carboxylic Acid Derivatives 991 21-5 Interconversion of Acid Derivatives by Nucleophilic Acyl Substitution 997... 

From these stractural features it is interesting to note that each molecule of chlorophylls a and b consists of a hydrophilic part (tetrapyrrole macrocycle) and a hydrophobic portion (long terpenoid chain of phytol esterifying the acid group at C-17). Figure 2.1.2 shows the structures and nomenclature of chlorophylls a and b and their major breakdown derivatives. 

In Chapter 9 you see the basic structure of each of the carboxylic acids and Ccirboxylic acid derivatives. In this chapter we focus on the carboxylic acids and related compounds, such as esters, acyl chlorides, and acid anhydrides, and we also include some information on amides (see Chapter 13 for an additional examination of cimides). Before you can get into synthesis and reactions, though, you need to understand the structure and nomenclature of these compounds. 

Structure and Nomenclature of Carboxylic Acid Derivatives A. Structure... 

Seeing the Structure and Nomenclature of Carboxylic Acids and Derivatives... 

Several important classes of molecules have the carbonyl unit (-C=0) as a key part of their structure. They are generically known as carbonyl compounds. The chemistry associated with carbonyl compounds is important to many chemical reactions. The carbonyl unit is reactive because it is polarized and also contains a weak and reactive 7i-bond. This chapter is primarily dedicated to learning the identity, structure, and nomenclature of the key carbonyl-containing functional groups, as well as the most fundamental aspects of their chemical reactivity. These include aldehydes, ketones, carboxylic acids, and carboxylic acid derivatives. 

The most abundant naturally occurring bile acids in higher vertebrates are derivatives of cholanic acid (1) (Fig. 1), a 24-carbon-atom steroid possessing the characteristic cyclopentanophenanthrene nucleus. The structure and nomenclature of this class of compounds have been described in detail by Fieser and Fieser (25), Kritchevsky (26), and Van Belle (27). 

A review has appeared on the analysis, structures, nomenclatures and reactions of acids derived from monosaccharides and polysaccharides. ... 

It was earlier considered that all the amino acid-activating synthetases were derived from a single primeval synthetase , so that all synthetases would have similar structures. Surprisingly, however, this is not the case. When the primary sequences, and in part the secondary and tertiary structures, of all the synthetases had been determined, clear differences in their construction became obvious. The aminoacyl-tRNA synthetases consist either of one single polypeptide chain (a) or of two or four identical polypeptides (ot2 or 04). In addition, there are heterogeneously constructed species with two sets of two identical polypeptide chains (OC2P2). This nomenclature indicates that, for each synthetase, a or P refers to a primary structure. The number of amino acids can vary from 334 to more than 1,000. 

Carboxylic acids and their derivatives are also an important part of Organic 11. We spend quite a few pages looking at the structure, nomenclature, synthesis, reactions, and spectroscopy of carboxylic acids. While on this topic in Chapter 12, we use a lot of acid-base chemistry, most of which you were exposed to in your introductory chemistry course. (For a quick review, look over a copy of Chemistry For Dummies or Chemistry Essentials For Dummies, both written by John T. Moore and published by Wiley.)... 

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