Carbohydrate name origin

The GC-MS data (Figure 16.11) of the violet zone of B. carterii revealed that the unchanged diterpenes (verticillatriene, cembrene A, and cembrene C) and the nortriterpenes with carbohydrate structure originated from the pyrolyzed triterpenes (Figure 16.12) of the a- and (3-boswellic acids, named 24-norursa-3,12-diene (compound 7), 24-norursa-3,9(ll),12-triene (compound 8), 24-noroleana-3,12-diene (compound 9), and 24-noroleana-3,9(ll),12-triene (compound 10). 

Chemical Abstracts prefers the sugar terms, especially in the trivial forms however, in some instances, the bicyclo nomenclature is also applied. Surveying the whole original literature, preference is doubtless given to carbohydrate names with frequent use of the trivial isohexide terms, followed by the bridged-systems labeling. The fused systems names are not in vogue. 

Many carbohydrates fit the general formula Cv(H20)T, so it is apparent how the name originated. Actually, they are polyhydroxy aldehydes or ketones. Glucose, C6H 206, is a typical monosaccharide. It is a six-carbon aldehyde with hydroxy groups on all of the other carbons. 

Some six hundred structures of naturally occurring carbogenic molecules appe on the pages which follow, together with the name of each compound and references to the original literature of successful chemical synthesis. Thus, Part Three of this book is effectively a key to the literature of chemical synthesis as applied to the complex molecules of nature. The survey does not include oligomeric or polymeric structures, such as peptides, proteins, carbohydrates and polynucleotides, which fall outside the scope of this book because they can be assembled by repetitive procedures. 

The word carbohydrate derives historically from the fact that glucose, the first simple carbohydrate to be obtained pure, has the molecular formula C6H,206 and was originally thought to be a "hydrate of carbon, C6(Tl20)6." This view was soon abandoned, but the name persisted. Today, the term carbohydrate is used to refer loosely to the broad class of polyhydroxvlated aldehydes and ketones commonly called sugars. Glucose, also known as dextrose in medical work, is the most familiar example. 

Systematic substitutive nomenclature may be used to name all organic molecules. However, those that are of animal or vegetable origin have often received trivial names, such as cholesterol, oxytocin and glucose. Biochemical nomenclature is based upon such trivial names, which are either substitutively modified in accordance with the principles, rules and conventions described in Chapter 4, Section 4.5 (p. 70), or transformed and simplified into names of stereoparent hydrides, i.e. parent hydrides of a specific stereochemistry. These names are then modified by the rules of substitutive nomenclature. Three classes of compound will be discussed here to illustrate the basic approach carbohydrates amino acids and peptides and lipids. For details, see Biochemical Nomenclature and Related Documents, 2nd Edition, Portland Press, London (1992). 

When the structures of derivatives of the parent compounds depart more and more from those of the original sugars, the bridged-system nomenclature may be advantageously applied over the carbohydrate terms. This could be the case when one, or both, of the OH groups on C-4 and C-8 is (are) absent, as in the deoxy series (see Section V,3), and also in the oxidation products (see Section V,4), where sugar-derived names become complex. 

From the structural point of view, this series of relatively simple compounds offers the possibility of verifying and refining the n.m.r. parameters of die various units of extension of carbohydrate chains of the N-acetyllactosamine type, namely, Fuc and NeuAc, both in different types of linkage (compare, Tables XIII, XIV, XVII, and XXI). Moreover the parameters of an additional N-acetyllactosamine unit in /3-( 1—>-3) linkage to Gal of the original unit can be established (see compound 60) such a structural unit is known to occur in various oligosac-... 

The name carbohydrates is derived from their origin they are formed through photosynthesis from CO2 and water and their general formula is Cn(H20)n or Cn(H20)n-x when they are constituted by polymers. Together with lipids and proteins, carbohydrates are one of the main constituents of foods. 

Carbohydrates form another class of biologically important molecules. They serve as a food source for most organisms and as a structural material for plants. Because many carbohydrates have the empirical formula CH2O, it was originally believed that these substances were hydrates of carbon, thus accounting for the name. 

Protein A (PA) is a cell wall component produced by over 98% of the strains of Staphylococcus aureus that have been tested. It was reported first by Verwey, then rediscovered by Jensen nearly two decades later Its name emphasizes the chemical class, since PA originally was believed to be a polysaccharide, but shown later to be a protein with little or no carbohydrate. The outsmnding functional property of PA is its ability to bind specifically to the Fc region of immunoglobulin molecules, especially... 

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