| 摘要 |
An improved process is described for preparing Schiff base condensation addu ct final products whose components comprise a protein having beneficial activit y in animals, and an aromatic o-hydroxy aldehyde, which comprises bringing together the above-mentioned components in an aqueous environment at a pH of 7.0 or higher to form a reaction mixture, under conditions effective to driv e said condensation reaction substantially to completion by removing from abou t 97.0 % to about 99.9 % by weight, preferably from about 98.0 % to about 99.0 % by weight of the water already present or produced during said condensation reaction, consistent with maintaining the integrity of the condensation reactants and adduct final product, and to assure a rate of conversion to sa id condensation adduct final product, i.e., with resulting yield of said condensation adduct final product of equal to or greater than about 98.5 % b y weight, preferably equal to or greater than about 99.5 % by weight based on the weight of the reactants. Preferred aromatic o-hydroxy aldehydes comprise o- vanillin; salicylaldehyde; 2,3-dihydroxybenzaldehyde; 2,6-dihydroxybenz- aldehyde; 2-hydroxy-3-ethoxybenzaldehyde; or pyridoxal. A very wide range of proteins may be employed. The improved process provides yields over 90 % and substantially quantitative conversion of the aldehyde and protein to the condensation adduct.
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