synthesis of various substituted 5-thio-2-pyridinecarboxylic acids and their derivatives is described by three methods , i.e. , displacement of nitrite from methyl 5-nitro-2-pyridinecarboxylate ( 10 ) by a thiol anion , alkylation of methyl 5-thio-2-pyridinecarboxylate derived from reaction of the diazotized methyl-5-amino-2-pyridinecarboxylate ( 5 ) with thiocyanate followed by borohydride reduction of the product , and alkylation of 5-thio-2-pyridinecarbonitrile followed by hydrolysis .
C0028137
nitrite
C0003075
anion