| 摘要 |
Hydroxocobalamin is obtained by reducing cyanocobalamin in acid solution by means of nascent hydrogen produced by adding granular zinc and then blowing an oxidising gas through the resultant liquid after it has been diluted with water. The grain size of the zinc may be from 200 to 1400 microns and the acid may be hydrochloric, hydrobromic, hydriodic or sulphuric acid. Reaction is preferably effected at ambient temperature and at atmospheric pressure using air as the oxidising gas. The zinc may be rendered insoluble by the addition of soda, potash, baryta or ammonia and the hydroxocobalamin crystallised from aqueous solution by the addition of tetrahydrofuran, dioxan or acetone. |
