3-Hydroxypyrazine-2-carboxylic acid20737-42-230 % similar 3-Methylpicolinic acid4021-07-230 % similar 4-Chloropyridine-2-carboxylic acid5470-22-430 % similar 2-Chloroisonicotinic acid6313-54-830 % similar 3-Chloroisonicotinic acid88912-27-030 % similar