反应详情

5-(4-Benzyloxycarbonylaminophenyl)-3-methyl-2(1H)pyrazinone (1.5 g) was treated with hydrogen bromide in acetic acid in a manner similar to that described in Example 20 to give the title compound as its hydrobromide salt (1.09 g) which on recrystallisation from ethanol/ether has m.p. >300° C.; ν(Nujol mull) 1632, 1640 cm-1.