2 5 dimercapto 1 3 4 thiadiazole solubility July 8, 2019 16 32 64 128 2 5-dimercapto-1 3 4-thiadiazole 2 5-dimercapto-1 3 4-thiadiazole dipotassium salt 2 5-dimercaptoterephthalic acid