Pyrimidines carboxylic acid amides

Bahrami K, Khodaei MM, Farrokhi A (2009) Highly efficient solvent-free synthesis of dihydropyrimidinones catalyzed by zinc oxide. Synth Commun 39 1801-1808 74. Gross GA, Wurziger H, Schober A (2006) Solid-phase synthesis of 4,6-diaryl-3,4-dihydro-pyrimidine-2(lH)-one-5-carboxylic acid amide derivatives a Biginelli three-component-condensation protocol based on immobilized beta-ketoamides. J Comb Chem 8 153-155 Desai B, Dallinger D, Kappe CO (2006) Microwave-assisted solution phase synthesis of dihydropyrimidine C5 amides and esters. Tetrahedron 62 4651 664 Kumar A, Maurya RA (2007) An efficient bakers yeast catalyzed synthesis of 3,4-dihydro-pyrimidin-2-(lH)-ones. Tetrahedron Lett 48 4569-4571 77. Zalavadiya P, Tala S, Akbari J, Joshi H (2009) Multi-component synthesis of dihydropyrimidines by iodine catalyst at ambient temperature and in-vitro anti mycobacterial activity. Arch Pharm 342 469-475... 

Imidazoles from purines o-Aminocarboxylic acid amides from pyrimidine ring Carboxylic acid amides from hydroxamic acid benzyl esters... 

No pyrimidine is formed in the absence of the above catalyst. Also N-subst carboxylic acid amides from esters s. N. Nakamizo, Bull. Chem. Soc. Japan 44, 2006 (1971). 

In fact, most pyrimidinecarboxylic acids are made by hydrolysis of the corresponding esters, nitriles or sometimes amides, many of which can be made more easily by primary synthesis than can the acids themselves. Thus, pyrimidine-5-carboxylic acid may be made by alkaline hydrolysis of its ethyl ester (62JOC2264) and pyrimidin-5-ylacetic acid (789 ... 

In the course of this study, the authors determined /Lvalues for dibenzyl, methyl phenyl, methyl p-nitrophenyl, di-p-tolyl, di-isopropyl and tetramethylene sulphoxides and for diethyl, dipropyl and dibutyl sulphites. The /Lscales are applied to the various reactions or the spectral measurements. The /Lscales have been divided into either family-dependent (FD) types, which means two or more compounds can share the same /Lscale, family-independent (FI) types. Consequently, a variety of /Lscales are now available for various families of the bases, including 29 aldehydes and ketones, 17 carboxylic amides and ureas, 14 carboxylic acids esters, 4 acyl halides, 5 nitriles, 10 ethers, 16 phosphine oxides, 12 sulphinyl compounds, 15 pyridines and pyrimidines, 16 sp3 hybridized amines and 10 alcohols. The enthalpies of formation of the hydrogen bond of 4-fluorophenol with both sulphoxides and phosphine oxides and related derivatives fit the empirical equation 18, where the standard deviation is y = 0.983. Several averaged scales are shown in Table 1588. 

In CHEC-II <1996CHEC-II(7)431>, it was shown that the cyano function in 3-cyanopyrazolo[3,4- / pyrimidines can be converted into an amide by hydrogen peroxide and that 3-carboxylic acid derivatives readily decarboxylate at 200 °C. Wan et al. <2001T5497> have reported that treatment of 217 with an acetic acid-hydrochloric acid mixture affords 218. Compound 218 was also obtained upon heating 219 in DMSO for 2 h. Compound 219 was obtained in turn via heating 217 in KOH (Scheme 13). It has been pointed out earlier that a CN function is readily replaced by amines. 

The 9-carboxy group of 4-oxo-4//-pyrido[l,2-a]pyrimidines was esterified and the ester was transformed to the amide. This amidation could not be carried out in the 1,6,7,8-tetrahydro series.58 The 4-oxo-1,6,7,8-tetrahydro-4A/-pyrido[l,2-a]pyrimidine-9-carboxylic acids undergo spontaneous decarboxylation.58,319... 

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