Medicinal interest pyridine

Introductory surveys of these groups form parts of two chapters in an excellent general volume on the chemistry of alkaloids.1,2 A short review dealing with selected alkaloids of potential medicinal interest includes mention of a pyridine alkaloid.3 A review on the use of n.m.r. spectroscopy in structural and conformational elucidation of piperidine, pyridine, and monoterpenoid alkaloids is not readily accessible.4... 

Changing the pK of an acidic or basic group in a molecule so that more of the compound exists in the ionized form at physiological pH lowers log D (at about pH 7) and, in general, should improve aqueous solubility. The improvement in solubility is limited, however, if the solubility of the neutral form of the compound (the inherent solubility) is very low. The situation is worsened if the starting pK is far from 7. We find this to be a particular problem with weak bases. Weakly basic pyridines, quinolines, quinazo-lines and thiazoles seem to be frequent members of combinatorial libraries. Understanding the ionization behavior of drugs and how this property relates to oral absorption is extremely complex and likely beyond the capability (and interest) of many medicinal chemists. The reader is referred to an excellent recent review in this complex area. ... 

Since the drug tolerance to this compound is high, it may be of interest as a medicine for treatment of gout and hyperuricemia, as well as an antihypertensive agent. IbP and its 1- and 3-substituted derivatives containing 3- and 4-pyridinyl moieties in the pyridine ring exhibited pronounced cardiotonic activity (81USP4276293). 

Two-substituted pyridines feature a structural unit containing in many small molecule compounds, which are of interest for material and medicinal research. A common method for their preparation is the displacement of halogen in the corresponding 2-halopyridines by action of nucleophiles. As a rule, yields for these transformations of inactivated 2-halopyridines are known to be low, and in most cases they require metal catalysis and drastic reaction conditions, such as a high temperature. 

Needless to say that this unexpected result is much more interesting than if the classic Ugi-4CR adduct 91 were obtained. Indeed, the importance of imidazo[l,2-a]pyridine and the related bicychc heterocycles has stimulated intensive studies on the scope and appHcation of this novel three-component reaction. There seems to be no major hmitation regarding the selection of aldehydes and isonitriles. For 2-aminoazenes, both heteroaromatic amidines and heteroaromatic guanidines participated in this novel 3CR. However, ahphatic amidines were found to be inactive. Many variants have since been reported from different research groups, both from academia and industry, because of the medicinal relevance of this family of heterocycles [47]. 

Heterocyclic compounds which contain a pyridine ring are frequently found in natural products. Accordingly, they are of special interest in pharmaceutical, agrochemical, and medicinal chemistry [117]. Also, a number of pyridine derivatives have been used in material chemistry [118]. Bipyridine groups are... 

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