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4 - hydroxy-2 - pyridone the natural alkaloid nucleus , is also an important class of pharmaceutical intermediates , such derivatives have anti-fungal , anti-bacterial , anti-viral and anti-tumor and other biological activity . Since the 1970s , the holly Zhongshengmycin H and Tenellin , such as a series of 2-1 pyridone alkaloids have been isolated , and also developed a series of new build 4 - hydroxy-2 - pyridyl ketones effective synthesis method. 4 - hydroxy-2 - the structural characteristics of the the pyridone natural alkaloids , synthesis and biological activity , were designed and synthesized on the basis of a series of 4 - hydroxy-2 - pyridyl ketones , including the following aspects of contents: 1. malonic acid as a starting material , thionyl chloride , reaction with phenylacetonitrile to form a ring to give 4 - hydroxy - 2 - pyridone intermediates . Obtained via Pd / C catalytic hydrogenation dechlorination, after methylation of N-methyl 4 - hydroxy - 5 - phenyl - 2 - pyridone . Then 4 - hydroxy - 5 - phenyl - 2 - pyridone and 3 - amino crotonic acid ethyl ester reaction of the compound 4 - methyl-8 - phenyl-6H- pyrano [3,2-c] pyridine - 2,5 - dione , and then by methylation to give the target compound 1,4 - dimethyl-8 - phenyl-6H- pyran and [ 3,2 - c ] pyridine - 2 ,5 - dione . 2 of 4 - hydroxy - 2 - pyridone compound of the methylation reaction of methyl position is in the N atom or O atom selectivity problems . As the 4 - hydroxy - 2 - pyridone compound of structure 1 containing N atoms and 4 , containing a hydroxyl group , so there may be the methylation of the N atoms and O atoms, methylation of two products . Iodomethane as the methylating agent, the reaction with NaOH aqueous solution as a solvent , to give the methylated product of N atoms . 3 DABCO induced 4 - methoxy-2 - pyridone compound of the demethylation reaction . First, we designed and synthesized a 6 ??- methoxy - 2 - pyridyl ketones as demethyl substrate , DMF as solvent , to give 4 - hydroxy-2 - pyridone in the the DABCO 90 ℃ presence reaction 5h compounds. 4 through experiments , we synthesized 19 4 - hydroxy-2 - pyridone compound , wherein there are two of the 3,4 - position and dihydro- pyran ring of 2 - pyridone compound , there are 11 not new compounds to see reported in the literature and by IR, NMR , low-resolution mass spectrometry and high resolution mass spectrometry to confirm their structure .
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