Pyridines

Abstract

Pyridine was discovered in the middle of the last century (Anderson, 1849) as a product of the dry distillation of bones. The first isolation of a pyridine derivative from living tissue was by Johns (1885) who obtained crystalline samples of trigonelline (N-methylpyridinium-3-carboxylic acid; 1) from the plant Trigonella foenum graecum. Biochemically however, the most important discovery concerning the natural occurrence and importance of pyridine derivatives can be traced back to the observations of Harden and Young (1904) that alcoholic fermentation by yeast requires a heat-stable, dialysable (i.e. low M _r ) fraction to which the name cozymase was given. During the period 1935–36, Warburg and his collaborators identified a hydrogen-transferring coenzyme, from red blood cells, as a dinucleotide of adenine and nicotinamide. Von Euler’s group then showed that cozymase was of a similar composition and only differed from the hydrogen transferring coenzyme by having 3 atoms of phosphorus per molecule, whereas the latter coenzyme contained 2 per molecule. These two redox coenzymes are what we now know as NAD (nicotinamide adenine dinucleotide) and NADP (nicotinamide adenine dinucleotide phosphate).