2-Mercaptoethanesulfonic acid Property

Density 

1.25 g/mL at 20 °C

solubility 

DMSO

form 

Powder

pka

pK1:;pK2:9.5(－1) (20°C)

BRN 

1098878

CAS DataBase Reference

3375-50-6(CAS DataBase Reference)

Safety

Hazard Codes 

C

Risk Statements 

34

Safety Statements 

26-27-36/37/39-45

RIDADR 

UN 3265 8/PG 3

WGK Germany 

2

F 

10-23

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H314Causes severe skin burns and eye damage

Precautionary statements

P280Wear protective gloves/protective clothing/eye protection/face protection.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P310Immediately call a POISON CENTER or doctor/physician.

2-Mercaptoethanesulfonic acid Chemical Properties,Usage,Production

Originator

Mistabronco,UCB,W. Germany,1973

Definition

ChEBI: An organosulfonic acid consisting of sulfonic acid having a 2-mercaptoethyl group attached to sulfur.

Manufacturing Process

2,100 g of β-S-thiuronium ethanesulfonate were placed in a solution of 2,100 cc of concentrated aqueous ammonia and 400 cc of water. The mixture was carefully warmed on a steam bath and an exothermic reaction ensured, at which point the β-S-thiuronium ethanesulfonate passed into solution. After standing for two hours at room temperature, the solution was concentrated until all of the excess ammonia had been removed.
The resultant clear solution from the ammonolysis reaction was processed through "Amberlite IR-120" ion exchange resin and converted into β-Smercaptoethanesulfonic acid in 93.7% yield (based on β-S-thiuronium ethanesulfonate).
It is expedient not to heat the reaction mixture rapidly since this increases the loss of ammonia and effects an incomplete reaction. Heating the mixture too rapidly may retard the ammonolysis reaction entirely. The amount of ammonia used is considered to be a satisfactory minimum and larger quantities of ammonia are not found to have any beneficial effect on the reaction. It is also expedient to remove the excess ammonia before processing the guanidinium β-mercaptoethanesulfonate solution through the ion exchange resin since the resin will also remove the ammonia with the result that the capacity of the resin for the exchange of guanidinium ions will be reduced.
Although the preparation of β-mercaptoethanesulfonic acid through the ammonolysis reaction is the preferred method, it is also possible to prepare the sulfonic acid by the sodium hydroxide hydrolysis of β-S-thiuronium ethanesulfonate followed by the ion exchange treatment. The resulting acid, however, is generally not as satisfactory as that prepared by the ammonolysis reaction.

Therapeutic Function

Mucolytic

Synthesis Reference(s)

Journal of the American Chemical Society, 77, p. 6231, 1955 DOI: 10.1021/ja01628a052