2- nicotinic amide, bromination

Imidazolone of a more complex structure was obtained by bromination of 2-(3-oxypropyl)amino-5-(oxopyridyl-4)nicotinic amide in the presence of alkali in 53% yield (94MI5). 

The influence of other groups in a pyridine or similar ring system is more difficult to assess because no kinetic data are available. The deactivating effect of the bromine atom in the 2-position is greater than that in the 3-position, while 2,6-dibromopyridine is very slow to react with dimethyl sulfate. Esters, amides, and nitriles of nicotinic and isonicotinic acids undergo fairly easy quaternization at about... 

The amides and hydrazides of pyridine-carboxylic acids arc of some importance, though their chemistry is not marked by unusual properties. Nicotinamide is, of course, an important compound, and isonicotinic acid hydrazide (isoniazid) is an antitubercular drug. Substituted derivatives are used as antidepressants. In general, however, these compounds show normal chemical behaviour. The amides undergo hydrolysis, dehydration and Hofmann bromination without difficulty. Their reduction has been much studied as a route to pyridine aldehydes. The Sonn-Muller reduction is not very satisfactory in this series, but the McFadyen-Stevens reaction is useful . Nicotinic acid diethylamide gives only poor yields of the aldehyde upon reduction with lithium aluminium hydride, but yields from the methyl-phenylamide are high. Most satisfactory is the reduction of nicotinic acid dimethylamide with lithium diethoxyaluminium hydride . 

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