Studies on pyrazines. 24. A simple and versatile synthetic method for 3‐alkoxy‐ and 3‐aminopyrazinecarbonitriles

Abstract

New and concise synthetic methods of 3‐alkoxy‐ and 3‐aminopyrazinecarbonitriles by nucleophilic displacement of 3‐phenylsulfonylpyrazinecarbonitriles are reported.

A REGIOSELECTIVE SYNTHESIS OF METHYL 7-AMINO-3-PHENYLTHIENO-[2,3-b]PYRAZINE-6-CARBOXYLATE

“…15 When phenylglyoxal was employed under Sato's conditions, it gave regioisomers 5a and 6a in 30-60% yield without selectivity. No regioselectivity was achieved upon carrying the acids or the solvents for the condensation.…”

Studies on pyrazines. Part 37. Synthesis of 6-propionylpteridine-2,4(1H,3H)-dione and its 1- and/or 3-methyl derivatives from marine natural products

“…The key compound, 6-prop-1-ynyl-1,3-dimethylpteridine-2,4(1H,3H)-dione 9, was synthesized by a four-step sequence of reactions starting from 3-methylaminopyrazinecarbonitrile 5 11, 12 (Scheme 1). Bromination of 5 was unexpectedly accomplished by the classical procedure, by treatment with bromine in aqueous acetic acid containing sodium acetate affording an 86% yield of bromopyrazine 6.…”