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2-Mercaptoethanol (also β-mercaptoethanol, BME, 2BME, 2-ME or β-met) is the chemical compound with the formula HOCH2CH2SH. ME or βME.
M 1627 (OTTO) 2-Mercapto ethanol, GR 99%+ Cas no 60-24-2 - used because the hydroxyl group confers solubility in water and lowers the volatility.