K-oxides have two characteristic absorptions in the ultraviolet, one at 216 mp and the other at 260 mp. With increasing substitution, a third absorption appears at 295 mp. In the infrared, the compounds exhibit characteristic absorptions of 9-f 0 at 7.4-7.8 and 11.4-11.8 p, The 1, il- dioxides of the pyrazine compounds above as well as several trisubstituted pyrazine compounds have been prepared and characterized. The 1, 4-dioxides also have two ...
