Schering Spa

Janus Farmaceutici S.r.l.

Biote Kfarma Srl

Alberto Reiner

Giuseppe Vita

Giueseppe Vita

The L-arginine salts of the mercaptoethansulphonic acid are active in the therapy of the bladder carcinoma and in the therapy and prevention of the cistinic kidney calculi. The saline derivatives with basic aminoacids and their alkyl esters are moreover devoid of side effects. The latter derivatives are prepared by reacting, in aqueous or aqueous-alcoholic medium, equimolar amounts of mercaptoethansulphonic acid, just prepared from an organic or inorganic salt thereof, and of the desired aminoacid.

Pharmaceutical compositions having therapeutical activity based on

For the preparation of compounds such as ranitidine, niperotidine and cimetidine a urea of the formula:

Process for the preparation of compounds with antiulcer action

To synthesize molecules with antiulcer action, specifically ranitidine, niperotidine and cimetidine, having the formula: ##STR1## wherein R.sub.1 is hydrogen or together with R.sub.2 represents the rest of a cycloaliphatic or heterocyclic optionally substituted ring with 5 or 6 carbon atoms, R.sub.2 represents H, alkyl, alkyl substituted with a simple or substituted aromatic ring or with a single or substituted heterocyclic ring, Ar represents a simple or substituted phenyl group, a simple or substituted heterocyclic aromatic group, N=1, 2, 3, 4, 5 or 6 and X represents CH--NO.sub.2, S, N--C.tbd.N, the compound (II) is prepared through the following process sequence: ##STR2## wherein Z=H, NO.sub.2, halogen and R.sub.3 =--(CH.sub.2).sub.n Ar, --(CH.sub.2).sub.n --SH, --(CH.sub.2).sub.n --S--S--(CH.sub.2).sub.n, --(CH.sub.2).sub.n --S--CH.sub.2 Ar Y being halogen. The urea of formula ##STR3## is converted in a first stage into the corresponding carbodiimide ##STR4## by reaction with triphenylphosphine and bromine in the presence of a strong base and in a second stage is obtained the desired compound by reaction with nitromethane or with a saline derivative of cynamide.

Synthesis of antiulcer compounds

Derivatives of mercapthansulphonic acid are active in the therapy of the bladder carcinoma and in the therapy and prevention of the cistinic kidney calculi. The saline derivatives with basic aminoacids and their alkyl esters are moreover devoid of side effects. The saline derivatives are prepared by reacting, in aqueous or aqueous-alcoholic medium, equimolar amounts of mercaptoethansulphonic acid, just prepared from an organic or inorganic salt thereof, and of the desired aminoacid.

For the preparation of saline derivatives of mercaptoethansulfonic acid belonging to the class of the salts of alkali metals and of the salts with basic aminoacids, the sodium salt of the acid is obtained with a process comprising the reaction between sodium bromoethansulfonate with thiobenzoic acid and sodium bicarbonate and subsequent reaction of the resulting sodium benzoylethansulfonate with ammonia in water solution.

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Cantu, Italy

Alberto Reiner