Letostan is a cyclic cysteine derivative with mucolytic properties, clinically used to treat obstructive bronchopulmonary diseases, including chronic bronchitis, emphysema, and asthma.
Viscotiol,Carlo Erba,France,1979
ChEBI: A dicarboxylic acid monoester that is the monoethyl ester of 2-{2-[(carboxymethyl)sulfanyl]ethyl}-1,3-thiazolidine-4-carboxylic acid. A mucolytic used in the treatment of chronic bronchopneumopathies and related conditions.
In an Erlenmeyer flask placed in an ice bath, and under a well-ventilated
hood, a solution of 0.1 mol of acrolein in 100 ml of ether was introduced, With
the aid of a bromine ampoule, 0.1 mol (= 11 ml) of the ethyl ester of
thioglycolic acid containing 0.5 ml of triethylamine was added drop by drop.
One hour after completion of the addition, there was added 0.1 mol (15.6 g)
of chlorhydrate of cysteine in alcoholic solution. The chlorhydrate of the
expected derivative, which appeared in the form of a thick oil, was
precipitated by addition of 0.1 mol (10 g) of potassium acetate in aqueous
solution. The abundant precipitate obtained was filtered and washed in water
and ether. The product was recrystallized in a minimum of absolute alcohol.
