反应详情

1 g (8.9 mmol) of histamine and 1.28 g (8.9 mmol) of 2-chloro-3,6-dimethylpyrazine in 10 ml of 2-propanol are brought to reflux for 3 days, evaporated and the residue is chromatographed on a column of silica gel, using mixtures of chloroform and methanol (1, 10 and 20% respectively) to give the title compound in the form of an oil. The latter is converted to a monohydrated dioxalate salt which is crystallized from an isopropanol/ether (1/1) mixture. M.p.: 164°-165° C.

1. temperatureto reflux for 3 days
2. customevaporated
3. customthe residue is chromatographed on a column of silica gel