Principal organic functional groups

While the enzymes involved in detoxication processes are nonspecific in the classical sense of intermediary metabolism, they often have distinct specificities both for organic functional groups and for the electronic, steric, and stereochemical environments where these functional groups are located. Enzyme specificity based on organic functional groups and their environments leads to a wide diversity in the alkaloid substrates possible and therefore the products obtained from biotransformation. This section of the chapter will concentrate principally on the enzymes themselves, including general concepts of substrate specificity and mechanism. 

Survey of Organic Synthesis , by Buehler and Pearson, Wiley, New York, 2 vols., 1970, 1977, discusses hundreds of reactions used to prepare the principal types of organic compounds. The arrangement is by chapters, each covering a functional group (e.g., ketones, acyl halides, and amines). Each... 

In accord with the general theme of this series, the chapter is organized principally according to the type of cyclopropyl functional groups as ligands. The literature covered in this chapter has been surveyed up to 1994. 

Tables 6.3-6.5 record data developed to undertake structural analysis in systems possessing chromophores that are conjugated or otherwise interact with each other. Chromophores within a molecule interact when linked directly to each other or when they are forced into proximity owing to structural constraints. Certain combinations of functional groups comprise chromophoric systems that exhibit characteristic absorption bands. In the era when UV-VIS was one of the principal spectral methods available to the organic chemist, sets of empirical rules were developed to extract as much information as possible from the spectra. The correlations referred to as Woodward s rules or the Woodward-Fieser rules, enable the absorption maxima of dienes (Table 6.3) and enones and dienones (Table 6.4) to be predicted. When this method is applied, wavelength increments correlated to structural features are added to the respective base values (absorption wavelength of parent compound). The data refer to spectra determined in methanol or ethanol. When other solvents are used, a numerical correction must be applied. These corrections are recorded in Table 6.5.

The usefulness of a book of this type depends principally on the compounds selected for inclusion. It is in order then that we describe briefly the basis for selection of the material included. The compounds included satisfy the following criteria (1) the compound either is not available commercially or if available is relatively expensive (2) directions for preparation of the compound had not been included in Organic Syntheses through Volume 28 and (3) the compound is one whose structure is simple and contains reactive functional groups which make it useful as an intermediate, or its preparation involves a generally useful type of organic reaction and the directions may be applied to the preparation of related compounds. 

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