Pyridine-2-carboxamide

Inhibitors for proteases plasmepsin I and II of the malaria parasite Plasmodium falciparum, with a good plasmepsin/human protease cathepsin D selectivity, have been identified via library construction involving rapid microwave-accelerated Suzuki reactions [57]. The phenyl ring of the biphenyl unit in the lead compound M-((lS)-l- [((lS,2S)-3- [(lS)-2-amino-l-(4-phenyl-benzyl)-2-oxoethyl]amino -2-hydroxy-l-phenoxypropyl)amino]carbonyl -2-methylpropyl)pyridine-2-carboxamide has been altered by performing Suzuki reactions on N-((lS)-l- [((lS,2S)-3- [(lS)-2-amino-l-(4-bromobenzyl)-2-oxoethyl]amino -2-hydroxy-l-phenoxypropyl)amino]carbonyl -2-methyl-propyl)pyridine-2-carboxamide (Scheme 37). In particular, a 2-benzofuryl moiety proved to be interesting since a Ki value of 13 nM for plasmepsin I and... 

The photodegradation of the contact herbicide paraquat yielded many degradation products, but the major pathway produced l,2,3,4-tetrahydro-l-ketopyrido[l,2-fl]-5-pyrazinium that was further degraded to pyridine-2-carboxamide and pyridine-2-carboxylate (Figure 1.11) (Smith and Grove 1969). 

A variety of gold(III) complexes of carboxamido substituted heterocyclic ligands are obtained by reaction of [AuCh] with the appropriate ligands, these include [Au (N,N )Cl2j (HN,N =picolinamide) (IS) [70], [Au(N,N, N")Cl]Cl [N,N H,N" = N-(8-quinolyl)pyridine-2-carboxamide (16), N-(8-quinolyl)glycine-2-carboxamide (17) or N-(8-quinolyl)-L-alanine-2-carboxamide (18)] [71] (Figure 2.11). 

Rowland et al. prepared a low-spin Fe(III) complex 24 from N, N-bis(2-pyridylmethyl) amine-N-ethyl-2-pyridine-2-carboxamide 23 (Scheme 3.31) [125]. When cyclohexene la reacted with complex 24 and a large excess of H202, among the oxidation products epoxide 4a predominated (TON 17). 

The hydrochlorides of 64, 65, and 66 were obtained by reaction of iV-phenylbenzimidyl chloride and hydrogen cyanide with the appropriate heterocyclic base. As is typical of the Reissert compounds, these three compounds lack absorption peaks in the region 2200-2400 cm h To further the analogy to Reissert compounds, acid-catalyzed hydrolysis of 64, 65, and 66 gave benzaldehyde. Picolinio acid, quinaldic acid, and isoquinaldic acid, respectively, as well as aniline, are also obtained from the hydrolysis. Nitrobenzene oxidation of the three compounds gave pyridine-2-carboxamide, quinaldonitrile, and isoquinaldonitrile, respectively. ... 

The photolabile [Fe—NO] iron nitrosyl complexes with a pentadentate ligand A ,A -bis(2-pyridylmethyl)amine-A -ethyl-2-pyridine-2-carboxamide, PaPyaH, and its derivative [(PaPyalFe (N0)](C104) have been synthesized in which the binding of NO is reversible and the bound NO is released rapidly under irradiation with visible light (78-80). 

In a similar fashion, as carboxylic acids or their esters, certain carboxamides possessing an ortho acyl group tnay also cyclocondense with hydrazine. Thus, Ar,/V-dicthyl-3-(2-pyridy car-bonyl)pyridine-2-carboxamide gives the corresponding pyrido[2,3-(i]pyridazin-H(7//)-one 15 in 89% yield, whereas, in contrast, 3-benzoyl-A, Ar-diisopropylpyridine-2-carboxamide and hydrazine give jV,2V-diisopropyl-5-phenylpyrido[2,3-d]pyridazin-8-amine (16) in 42% yield.50... 

Pyridine-2-carboxamides may be prepared in a ring-opening reaction of 2-methyl- or 2-phenylpyrido[3,2-d][l,3]oxazin-4-one with various amines.424... 

In the course of the synthesis of potential D1 agonists, DoM of pyridine 2-carboxamide derivatives X = CR, Y = N, R = H, Me, F, OMe, n-Pr, and R = H, Me, w-Bu with 2 equiv of BuLi followed by Michael addition of nitroolefin and a triethylamine-mediated equilibration gives the trans-lslnlm products (eq 54)... 

PaPysH N,N-6 (2-pyridylmethyl)amine-N-ethyl-2-pyridine-2-carboxamide... 

Crystals of the complex [Ni(H20)2(piaH)2]Cl2 are blue needles and have a magnetic moment of 3.25 BM. Pyridine-2-carboxamide, abbreviated piaH, may be expected to act as a bidentate ligand in two ways as shown. 

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