Pyridine amides

Acetonitrile and benzonitrile, aliphatic amines, pyridine, amides (especially DMF), alcohols, and propylene-carbonate are used as solvents in the syntheses of this type. All of them have properties of ligands. Moreover, such classic N-donors as 2,2 -bipy and 1,10-phen were used as ligands, as well as compounds with P-(triphenylphosphine) and O- donor centers (urea, pyridine-N-oxide, triphenyl-phosphinoxide) and chelating ligand systems ((3-diketones, 8-hydroxyquinoline, dimethylglioxime) [202]. 

Imidaxole, (IV), thiazole, pyrimidine, and pyridine amide derivatives were also prepared by the author in a subsequent investigation and are described (5). 

Pyridine amide, derived from (5)-desmethyl-MAP, induces high enantioselectivity in Cu-catalyzed conjugate addition of Et2Zn to enones (eq 10). ... 

The cycloaddition does provide a useful route to certain pyridine derivatives. - For example, oxygenated dienes (67) add to oximino dienophile (68) to afford adducts (69) in a totally regioselective manner (equation 22). Treatment of this adduct with base provides the pyridine amide (70). 

This process involves a straightforward directed ortho metallation (chapter 7) of the pyridine amide 206 and capture by the indole aldehyde 208. Without work-up, the product 209 is lithiated again and the ellipticine quinone 210 is formed in good yield.26... 

It is also possible to introduce a nitrogen function using these types of process 0-tosylation then t-butylamine as a synthon for ammonia leads to 2-aminopyridines and oxalyl chloride, together with a secondary amide, produces 2-amino-pyridine amides. ... 

Figure 8 Dot surface indicates the van der Waals surface of the AtHPPD protein. Proposed inhibitor DAS432 shown with good fit to protein surface and the chloro-pyridine amide tail occupies a previously unexplored channel...

Curtius reaction, conversion of a pyridine hydrazide to a pyridine amide, 362 Cyanoacetamide, 602, 620 Cyanoacetic acid, 601 Cycloalkano-2-pyridones, preparation from 2- (2-cymo-ethyl) cycloalkanones, 729 a-Cyano-2-butenolc acids, 601... 

Fig. 12.23 Structure of strapped calix[4]pyrroles 36 and the potassium cation carrier valinomycin (top), the pyridine amide strapped calix[4]pyrrole 37, and single crystal structure of its [37 NaCl] complex (middle). TBA cation, water, and hexane molecules in the crystal structure were omitted for clarity. This X-ray figure was reproduced using the data downloaded from the Cambridge Crystallographic Data Centre. The Na transporter monensin, and the Na" channel blocker amiloride (bottom)...

Deamidation of Nicotinic Add. Enzymes from microorganisms (185-188), insects (189), and birds have been found to deamidate nicotinamide to nicotinic acid (190). Recently, Sundaram et al. (191) have shown that a strain of Leuconostoc mesenteroides which will grow on nicotinic acid but not on nicotinamide, does not possess the deamidase and will not convert the pyridine amide to DPN. On the other hand, Saccharomyces cerevisiae will grow on both pyridine compounds, and the yeast contains the deamidase. These observations suggest that the route of synthesis of DPN from nicotinamide may involve the Preiss-Handler pathway, and that deamidation of nicotinamide occurs during the synthesis, which is also indicated by studies in the intact mouse (see Section III, A). 

Arnett s data for 44 bases with the single hydrogen-bond donor 4-fluorophenol in CCI4 did not confirm the existence of a general AH—AS correlation [11]. However, in a plot of AH versus AG, some of the data could be resolved into separate lines corresponding to the families of pyridines, amides, sulfoxides and phosphoryl bases. Unfortunately, there were not enough data for other families of bases to enable this observation to be extended. 

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