Acylaminopyrazines

Acylaminopyrazines have been deacylated by hydrolysis in acid, or alkali, by methanolysis, or by hydrazinolysis (in propan-2-ol) under a variety of conditions to give the corresponding amino compound unless otherwise specified in the following examples 2-acetamido-3-acetoxymethylpyrazine (28) (dilute acetic acid at reflux for 6h) (1075) 2-acetamido-5-chloro-3-amidinocarbamoylpyrazine (5% hydrochloric acid-acetic acid at 100°) (150) 2-acetamido-3-A(-(benzimidoyl)-carbamoyl-5-chloropyrazine (5% hydrochloric acid at room temperature) (150)  

3- guanidinocarbonylpyrazine (10% hydrochloric acid at 100° for 15 minutes) (432, 1158) 2-acetamido-5-chloro-3-(2, 3 -diphenylguanidinocarbonyl)pyrazine (5% aqueous hydrochloric acid in isopropanol) (783) 2-(butylthio)carbonyl-3,5- 

2-(2 -C yanoethyl)carbamoyl-3-formylamino-5-methylpyrazine boiled with N sodium hydroxide for 30 seconds gave 3-amino-2-cyanoethylcarbamoyl-5-methyl-pyrazine (435) 2,3-dichloro-5-formamido-6-formylpyrazine was readily deformyl-ated under acid or alkaline conditions (e.g., 2A( sodium carbonate at 20°) (430) and 2-formamido-3-(iniidazol-2-yl)pyrazine was deformylated by refluxing with 0.1 A hydrochloric acid for 4 hours and its 5,6-dimethyl derivative reacted similarly (455a). 

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CONDENSATION OF o -BROMOPROPIONYL (OR o-BROMOPHENYLACETYL) DERIVATIVES OF AMINOMETHYL KETONES WITH AMMONIA TO ACYLAMINOPYRAZINES... 

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