反应详情

Glutaryl 7ACA (4.0 g) is slurried in 60 ml water and the pH is adjusted to 3.5 to 4.0 with 20% sodium hydroxide to dissolve the glutaryl 7ACA. To the solution is added 2.2 g calcium chloride and the pH is adjusted to 5.5 to 6.0 with 20% sodium hydroxide. Yeast esterase (0.4 g) is added and the solution is stirred at 22°-25° C. for 2.5 hours while maintaining the pH at 5.9-6.1 with 20% sodium hydroxide. The yield by HPLC to desacetyl glutaryl 7ACA is 97% with the ratio of desacetyl glutaryl 7ACA to glutaryl 7ACA >99%. The resulting solution is filtered with filter aid to remove the yeast and is diluted with water to 90 ml. Desacetyl glutaryl 7ACA calcium salt is precipitated by the addition of 450 ml ethanol. The crystals are filtered, washed with ethanol, and dried. Subsequent crystals which come out in the filtrate are similarly filtered and dried. (Crystal purity as desacetyl glutaryl 7ACA is 63%). The crystallization yield is 83%. The desacetyl glutaryl 7ACA calcium salt was characterized by NMR and IR:

1. additionYeast esterase (0.4 g) is added