反应详情

The procedure of Example 4 was repeated for the screening of the KRED-8000 kit with 3-benzyloxaloacetate diethyl ester. Enzymes KRED 1008 and KRED 1004 showed complete reduction to the alcohol. Both reactions were repeated in larger scale for the purpose of isolating the product and verifying the structure using 1H NMR spectroscopy. In 20 mL of an aqueous solution containing 250 mM potassium phosphate (pH 6.7), 5% (v/v) polyethelene glycol (MW 1450) 0.5 M sodium chloride, 0.076 g of NADP+, 3.5 g of D-glucose 0.1 g of both lyophilized enzymes glucose dehydrogenase and KRED 1004 or KRED 1008 0.5 g of 3-benzyloxaloacetate diethyl ester were added. The reactions were incubated at 37 C in a shake oven for 20 h before they were extracted with ethyl acetate. The organic layers were evaporated to dryness, and the alcohols were further purified using silica gel chromatography, before they were analyzed by 1H NMR. Both enzymes gave 2-hydroxy-3-benzylsuccinate diethyl ester as the only product.

1. customof isolating the product
2. additionwere added
3. extractionwere extracted with ethyl acetate
4. customThe organic layers were evaporated to dryness
5. customthe alcohols were further purified