document: The α-ω-aminohexylcarbamate derivative of cyanocobalamin was prepared using a method described previously [18]. Briefly, solid CDI (260mg, 0.32mmol) was added to cyanocobalamin (1.0g, 0.148mmol) previously dissolved in anhydrous dimethyl sulfoxide. The mixture was stirred for up to 2h at 30°C, followed by the addition of dry 1,6-hexanediamine (314mg, 0.54mmol) and stirring of the mixture at room temperature over 24h. The mixture was poured into ethyl acetate (30ml) and left to stand. Following centrifugation and decanting of the supernatant, the residue was sonicated for 5min in acetone (50ml). The resulting precipitate was filtered and the solid washed in acetone. The crude product was purified by silica column chromatography (45% v/v 2-propanol, 30% v/v n-butanol, 2% v/v ammonia and 25% v/v water) followed by lyophilisation.
doc_bio_tags: O O O O B O O O O O O O O O B O O O O O O B O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B O B O O B O B O O O O O B O O O B O O O O B O O B O B I O O O B I I O O O O O O O O B O O O B O O B
extractive_keyphrases: acetone ammonia anhydrous dimethyl sulfoxide centrifugation crude product cyanocobalamin decanting ethyl acetate lyophilisation precipitate residue silica column chromatography solid supernatant water
abstractive_keyphrases: butanol dry 1,6-hexanediamine propanol solid cdi α-ω-aminohexylcarbamate derivative of cyanocobalamin