On Reuben G. Jones synthesis of 2-hydroxypyrazines

• Pierre Legrand and
• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 935–943, doi:10.3762/bjoc.18.93

• occurrence of 3,5-substituted-2-hydroxypyrazine as the major reaction product. Keywords: α-aminoamide; condensation; hydroxypyrazine; methylglyoxal; phenylglyoxal; Introduction In a recent report [1], the many ways a pyrazine nucleus is able to interact with proteins were reviewed. In this text, it was

• expected 3,5-substituted-2-hydroxypyrazine isomer (3, R1 = H, R2 ≠ H) which is isolated sometimes along with a much smaller amount of the alternative 3,6-substituted-2-hydroxypyrazines (4, R1 = H, R2 ≠ H) [6][13][18][19][20][21][22][23][24][25][26][27][28]. This regioselectivity appears counterintuitive

• addition of concentrated hydrochloric acid. When relevant, this is followed by a dilution in an excess of water and then a filtration and washing. This procedure provides average yields of the 3,5-substituted-2-hydroxypyrazine 3 isomer as the major reaction product sometimes along with lesser amounts of