THE preparation of dihydropteroylglutamic acid has previously been described by O'Dell et al., who used catalytic hydrogenation of pteroylglutamate1, and by Futterman, who carried out the reduction with sodium dithionite2. The acid prepared by catalytic hydrogenation is unsuitable for many biochemical studies, however, because it contains traces of tetra-hydropteroylglutamic acid3. The material obtained by the method of Futterman is an amorphous discoloured preparation2, but was found to be uncontaminated by tetrahydropteroylglutamic acid3. No analytical figures have been given for this material. By reducing purified pteroylglutamate with sodium dithionite according to the method of Futterman and twice precipitating the product by slow adjustment of the pH. between strictly defined values, it has now been found possible to obtain dihydropteroylglutamic acid consistently as a white crystalline product giving analytical results agreeing fairly well with the theoretical values.
                                    O'Dell 等人曾描述过二氢teroyl 谷
氨酸的制备方法,他们使用的是蝶酰谷
氨酸的催化加氢法1, Futterman 则使用了
连二亚硫酸钠还原法2。然而,催化加氢法制备的酸不适合用于许多生化研究,因为其中含有微量的四氢特戊酰基谷
氨酸3。用 Futterman 方法制备的材料是一种无定形的变色制剂2 ,但发现没有受到四氢特戊酰基谷
氨酸的污染3。没有给出这种材料的分析数据。根据 Futterman 的方法,用
连二亚硫酸钠还原纯化的蝶酰谷
氨酸,并通过缓慢调节 pH 值,在严格规定的值之间沉淀两次,现已发现可以稳定地获得白色结晶的二氢蝶酰谷
氨酸,其分析结果与理论值相当吻合。