Rhone-poulenc Industries

Rhone-poulenc Sante

Rhone-poulenc Rorer S.a.

Gerard Wolff

Daniel Farge

Claude Moutonnier

Christian Berger

Claude Bertrand

Isidore Le Fur

Jean-Paul Richard

Dominique Deprez

Process for preparing pure ascorbic acid from 2-keto-L-gulonic acid or its sodium salt, by carrying out the following successive steps:

Process for preparing ascorbic acid

The hydrated complex of magnesium acetylsalicylate and urea of formula ##STR1## possesses exceptional analgesic and antipyretic properties. It may be crystallized from a solution obtained by reacting acetylsalicylic acid with magnesium carbonate in the presence of urea.

Acetylsalicylic acid derivative and pharmaceutical composition thereof

Hydrated magnesium acetylsalicylate/urea complex preparation

The invention provides new cephalosporin derivatives of the general formula, ##STR1## which are in the form of a bicyclooct-2-ene or bicyclooct-3-ene, in which formula R.sub.1 is a radical of the general formula ##STR2## [in which R.sub.5 is hydrogen, alkyl, vinyl, cyanomethyl, protected carboxyalkyl or a protective radical and R.sub.6 is a protective radical] or an amino-protecting radical, R.sub.2 is an acid-protecting radical and R.degree. represents various organic radicals, or alternatively R.sub.1 is an amino-protecting radical or various acyl radicals, R.sub.2 is a protective radical and R.degree. represents various organic radicals, and R.sub.3 and R.sub.4 are alkyl radicals optionally substituted by alkoxy or dialkylamino, or phenyl radicals, or --NR.sub.3 R.sub.4 forms a heterocyclic ring. These products are intermediates for the synthesis of cephalosporins having antibacterial activity.

Cephalosporin derivatives

New thiazolo[3,2-c]-1,3-benzoxazine derivatives of the general formula (I), in which X is oxygen or sulfur, R.sub.1 and R.sub.2, which are identical or different, are hydrogen or halogen atoms or alkyl, alkoxy, alkylthio or trifluoromethyl radicals, in the 7-, 8-, 9- or 10-position, and R.sub.3 is a hydrogen atom or a carboxyl radical, their salts, if appropriate, their preparation and the medicaments in which they are present. These new derivatives are particularly useful as analgesic agents. ##STR1##

Thiazolo(3,2-C)benzoxazine derivatives

.alpha.-Amino(1,3-dithiin-5-yl)-acetic acid in the D-, L-, or D,L-form and in which the amino radical is free or protected by tert.-butoxycarbonyl or 2,2,2-trichloroethoxycarbonyl is a useful intermediate in the preparation of cephalosporins having valuable antibacterial activity.

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Thiais, France

Gerard Wolff