Réaction #94670

Équation de réaction

NAD

phthalimide

hydrochloric acid

→

4-(3-aminopropyl)-pyrazole dihydrochloride

Conditions de réaction

Traitement

1. 1
   Autrephthalic acid removed by filtration
2. 2
   Autrethe filtrate evaporated to dryness
3. 3
   Autreto give a product which
4. 4
   Autreafter recrystallization
5. 5
   workup.ADDITIONfrom a mixture of ethanol and ethyl ether
6. 6
   AutreThis pyrazole compound could be coupled to the activated dextran by reaction of the terminal amino group

Mode opératoire

This phthalimide intermediate (8.0 gram, 0.03 mole) was refluxed in 100 ml. of 6 normal hydrochloric acid overnight. The clear solution was cooled to 4° C., phthalic acid removed by filtration, and the filtrate evaporated to dryness to give a product which, after recrystallization from a mixture of ethanol and ethyl ether, amounted to 4.4 grams of a white solid identified as 4-(3-aminopropyl)-pyrazole dihydrochloride, melting point 189°-190° C. This pyrazole compound could be coupled to the activated dextran by reaction of the terminal amino group, but the resulting affinity resin, in which the coupling arm had a length of only 6 Angstrom units, had poor binding capacity for the binary complex of alcohol dehydrogenase and NAD.

Source