Ethyl esterification and acylation of L-alanine with oxalic acid and ethanol to obtain N-ethoxyoxalyl-L-alanine ethyl ester, followed by cyclization and decarboxylation to obtain 4-methyl-5-B Oxygen (oxo) azole, and finally with 2-isopropyl-4,7-dihydro-1,3-di(oxo) gemide by Diels-Alder reaction to obtain vitamin B6, the total yield of 54%. This method is low in cost and suitable for industrial production.

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