3.2.2. Synthesis of 2-((1H-1,2,4-Triazol-3-yl)thio)acetic Acid (3)

A mixture of compound 1 (10 mmol) with the chloroacetic acid (10 mmol) and anhydrous sodium acetate was refluxed for 2 h in glacial acetic acid (10 mL). The white solid obtained was filtered, washed with ethanol and recrystallized from glacial acetic acid. Yield 76%, white powder, mp 132–134 °C (acetic acid). ¹H-NMR (500 MHz, DMSO-d₆, δ): 13.99 (brs, NH), 12.80 (brs, COOH), 8.47 (brs, 2-H), 3.91 (2H, s, CH₂). ¹³C-NMR (126 MHz, DMSO-d₆, δ): 170.0, 158.1, 144.8, 33.7. LCMS (ESI+) m/z 160 [M + H]⁺. Anal. calc. for C₄H₅N₃O₂S: C 30.19; H 3.17; N 26.40. Found: C 30.30%, H 3.40%, N 26.60%.