Organic nitrogenous bases

The cation in an ionic liquid typically is an organic nitrogen-based ion such as alkyl ammonium, alkyl pyridinium, or dialkylimidazolium, examples of which appear below. 

The nature of such sites seems consistent with the behavior shown In the pyridine and lutldlne poisoning experiments. The acidic nature of the reduced metal sites which hold the nitrogen bases seems established. Difference In the extent to which the exposed metal cation Is accessible to the nitrogen atom of the organic nitrogen base could explain the selective poisoning seen with different substituted pyrldlnes. Presumably the cations In an active pair are somewhat less accessible than most exposed Co and Mo cations, which, because they normally hold two MO molecules, are probably exposed In Incomplete tetrahedral sites. 

The nucleotides of RNA and DNA consist of three components a carbohydrate, a phosphate group and an organic nitrogenous base. There are two types of carbohydrate molecule in nucleic acids, both of which are D-pentoses, i.e. contain five carbon atoms. The carbohydrate in RNA is ribose, while DNA contains deoxyribose, which has a hydrogen atom instead of a hydroxyl group attached to the carbon in the 2 position (Figure 13.1). 

The cobalt molybdate catalyst is also suitable for the reduction of organic nitrogen bases (30). From Colorado-shale-oil fractions containing 2% N2 and 0.7% sulfur, jet and Diesel fuels have been obtained with 0.01 to 0.1% N2 and 0.03 to 0.04% sulfur. 

A large number of dinitramide salts have been reported in the literature. They are formed with metallic cations or with protonated organic nitrogen bases. 

DNA is composed of three chemical functions A deoxyribose (a pentose, i.e., a sugar with five carbons), organic (nitrogenous) bases (pyrimidines cytosine and thymine purines adenine and guanine), and a phosphoric acid. 

In most fluorides with organic nitrogen bases, these are protonated and enter the stmcture as counter cations. However, the example of 4,4 -bipyMnF3 (bipy = bipyridine) shows that it is also possible to consfruct hybrid coordination polymers with the amine and fluoride as bridging ligands (Figure 40). The stmcture is modulated at low temperature and has ID magnetic properties ... 

Walker, S.T. Liquid chromatographic determination of organic nitrogenous bases in dosage forms a progress report. J.Assoc.Off.Anal.Chem., 1985, 68, 539-542... 

Racz3fuska, E.D., Decouzon, M., Gal, J.-E. et al. (2001) Gas-phase structural (internal) effects in strong organic nitrogen bases. Journal of Physical Organic Chemistry, 14, 25-34. 

A typical example is the determination of organic nitrogen bases (mainly of alkaloids, dyestuffs, and of several pharmaceuticals, e.g., phenothiazine derivatives, antihistaminics, and spasmolytics) after their precipitation with electroactive inorganic anions (such as silicotungstates or Bil4T) and appropriate dissolving of the precipitates. 

Certain organic nitrogen bases show exceedingly small basic properties in water, so that they cannot be determined by acidimetric titrations they can, however, readily be titrated in solutions of acetic acid using perchloric acid, since acidic solvents are levelling solvents for bases. It is obvious that in most protonic solvents normal pH-color indicators can be used to follow acid-base reactions. 

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