Carbohydrates, acidic derivatives VOLUME

The next two sections of this review chapter will introduce the reader to the world of lactic acid. The acid is both a key platform chemical of the biorefinery concept, from which other interesting molecules may be formed (Sect. 2), and a monomer for commercial bioplastic polylactic acid (PLA) (Sect. 3). In the platform approach, the assessment from Chap. 1 in this volume [23] proves its value, as it is an equally useful tool to seek out the most desired routes for transforming a biomass-derived platform molecule as it is to select the most relevant carbohydrate-based chemicals from a chemist s point of view. In what follows, the desired catalytic cascade from cellulose to lactic acid will be described (Sect. 4) as well as the specific catalytic data reported for different feedstock (Sects. 5 and 6). Section 7 will introduce the reader to recent synthesis routes for other useful AHA compounds such as furyl and vinyl glycolic acid, as well as others shown in Fig. 1. Before concluding this chapter, Sect. 8 will provide a note on the stereochemistry of the chemically produced AHAs. 

The latest volume in the series Methods in Carbohydrate Chemistry reports a number of useful techniques, including the proteolytic digestion of membrane-derived glycoproteins, the acid-catalysed hydrolysis and methanolysis of glycoproteins, and the detection of residues linked 0-glycosidically to serine and threonine, Among other methods described are the use of enzymes in the... 

Owing to the reactivity of succinic acid, it can be converted to a variety of products, including large-volume chemicals such as 1,4 butanediol and tetrahydrofuran. The use of renewable resources and carbohydrates derived from agricultural materials... 

Tables 8 and 9 mention many organic ligands, or at least their basic units, which may be bound as substrates, products, or analogs to proteins and other biopolymers. The tables also comprise volume data for urea and guanidinium salts, amino acids, betaines, and peptides, nucleobases, nucleosides, and nucleotides, carbohydrates, lipids and constituents, detergents, as well as some derivatives of these substances. Moreover, Table 9 lists a variety of volumes found for inorganic electrolytes. Molecules not found in the tables can be estimated by the universal approach outlined in section 4.4.2.

Table 9. Further experimental specific volumes of some selected small molecules and polymers under different environmental conditions. Some values presented in this table were taken from [86D1] for detergents and lipids primarily the compilation in [78S1] was used most values for electrolytes were derived from the partial molar volumes cited in [72M1]. Only in a few cases, calculated volumes (Vg) were mentioned instead of experimental ones. Note that a great number of values (e.g., for amino acids, betaines, small peptides, carbohydrates, lipids, nucleobases, denaturants, detergents, substrates, products and analogs of enzymic reactions) are given in Table 8.

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