Methylamine → Regadenoson

Participants

Reaction Steps

A mixture of ethyl 1-{9-[(4S,2R,3R,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]-6-aminopurin-2-yl}pyrazole-4-carboxylate (46.4 g) and methylamine (40% in water, 600 ml) was stirred at ambient temperature for about 4 hours, following the progress of the reaction by HPLC analysis. The majority of the excess methylamine was removed under reduced pressure, and the remaining mixture cooled at 0° C. for 2 hours. The solid material was filtered off, washed with ice-cold 200 proof ethanol, and dried under reduced pressure, to provide (1-{9-[(4S,2R,3R,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]-6-aminopurin-2-yl}pyrazol-4-yl)-N-methylcarboxamide as its monohydrate, 36.6 g, purity 99.6%.

Provenance & Evidence