Biological Activity and Uses

Pyrazines are known to exhibit a range of physiological activities. For example, 2-carbamoylpyrazine ( pyrazinamide ) is used in the treatment of tuberculosis (138-141). In animals pyrazinamide was at least twice as active as p-aminosalicyclic 

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By Formation of Two Bonds from [3 +3] Atom Fragments 2.15.16 BIOLOGICAL ACTIVITY AND USES OF PYRIDODIAZINES... 

The physicochemical properties that correlate with the biological property are likely to be related to the mechanism by which the chemicals cause the biological activity, and are often referred to as descriptors of the biological activity. Examples of physicochemical properties that often correlate with biological activity and used in the quantification of SARs include octanol-water partition coefficient (logP0/w), dissociation constant (p/<,), and molar refractivity (MR), among others. 

Diamines are another highly useful class of molecules with potent biological activity and use as synthetic intermediates and metal ligands. The ring-opening reactions of aziridines with amines and azide provides a facile route for the synthesis of 1,2-diamines. 

Hydrogen cyanide (HCN) is also chemically identified by the synonyms formonitrile, prussic acid and hydrocyanic acid. The physicochemical properties most related to the biological activity and uses of HCN are summarized in Table 1. Notable with HCN is that it is a low boiling point liquid (26.5°C). Related to its low MW (27.04) it has a high vapor pressure (600 mm Hg at 20°C) and low vapor density (0.947 at 31°C), Thus,... 

While the lanthanides do not appear to be biologically essential elements, they are certainly biologically active and useful in many ways, and their applications in medicine, in particular, continue to expand. In a recent review focussed on a broad range of applications of lanthanide ion... 

Despite these improvements, many of the limitations of the hybridoma technique persist. First, it is slow and tedious, and labor- and cost-intensive. Second, only a few antibody-producing hybridoma fines are created per fusion, which does not provide a broad survey of the immunologic repertoire. Third, the actual antibody production rate is low. Fourth, it is not easy to control the class or subclass of the resulting antibodies, a characteristic that often determines their biological activity and usefulness. 

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