Lonza Inc.

Sankyo Company, Limited

David Laffan

Aleksander Warm

John McGarrity

Markus Banziger

Process for the production of 4-hydroxy-2-oxoyrrolidin-1-yl-acetamide, a cerebrally active pharmaceutical agent. A 4-halo-3-alkoxy-butenoic acid ester is reacted with glycine to new intermediate products of the formula: ##STR1## There is further by acid hydrolysis of the alkoxy group, subsequent hydrogenation, esterification of the carboxyl function and finally conversion to the end product by reaction with ammonia.

Process for the production of 4-hydroxy-2-oxopyrrolidin-1-yl-acetamide

A novel process the preparation of pentaalkylchromenes of the general formula: ##STR1## wherein R denotes a lower alkyl group having 1 to 4 C atoms and R.sub.1 denotes a phenyl group which is unsubstituted or substituted by a lower alkyl group having 1 to 4 C atoms, by halogen or by a nitro group, or an alkanoyl group having 1 to 4 C atoms. In the process, a trialkylhydroquinone is reacted with a halogenated butenol to give a substituted tetraalkyhydroquinone, which is oxidized. Then the halogen atom is substituted with a suitable nucleophile and the compound is finally cyclized to give the final product. The pentaalkylchromenes are suitable intermediates for the preparation of hypolipidaemic pharmaceuticals.

Process for the preparation of substituted pentaalkylchromenes

A process for the production of substituted vinylbenzenes of the general formula: ##STR1## wherein R is a lower alkyl group having 1 to 4 C atoms, R.sub.1 is hydrogen or an acetyl group and R.sub.2 is hydrogen, a lower alkyl group having 1 to 4 C atoms or a benzyl group. A trialkylhydroquinone is cyclized with an aldehyde to an acetal and the latter is pyrolized to the end product. The substituted vinylbenzenes are valuable intermediate products in the synthesis of antioxidants.

Process for the production of substituted vinylbenzenes

The substituted pentaalkylchromans of the general formula: ##STR1## wherein R denotes a lower alkyl group having 1 to 4 C atoms and Hal denotes chlorine, bromine or iodine, are novel intermediates for the preparation of hypolipidaemic pharmaceuticals. A process for their preparation is described in which a trialkylhydroquinone is reacted with a halogenated butenol to give a substituted tetraalkylhydroquinone, which is finally cyclized to the final product.

Substituted pentaalkylchromans

A novel process for the preparation of pentaalkylchromenes of the general formula: ##STR1## wherein R denotes a lower alkyl group having 1 to 4 C atoms and R.sub.1 denotes a phenyl group which is unsubstituted or substituted by a lower alkyl group having 1 to 4 C atoms, by halogen or by a nitro group, or an alkanoyl group having 1 to 4 C atoms. In the process, a trialkylhydroquinone is reacted with a halogenated butenol to give a substituted tetraalkyhydroquinone, which is oxidized. Then the halogen atom is substituted with a suitable nucleophile and the compound is finally cyclized to give the final product. The pentaalkylchromenes are suitable intermediates for the preparation of hypolipidaemic pharmaceuticals.

A process for the production of substituted vinylbenzenes of the general formula: ##STR1## wherein R is a lower alkyl group having 1 to 4 C atoms, R.sub.1 is hydrogen or an acetyl group and R.sub.2 is hydrogen, a lower alkyl group having 1 to 4 C atoms or a benzyl group. A trialkylhydroquinone is cyclized with an aldehyde to an acetal and the latter is pyrolized to the endproduct. The substituted vinylbenzenes are valuable intermediate products in the synthesis of antioxidants.

Threo-4-alkoxy-5-(arylhydroxymethyl)-2(5H)-furanones are obtained by condensation of 4-alkoxy-2(5H)-furanones with benzaldehydes in the presence of lithium hydroxide without contamination by the corresponding erythro stereoisomers. The condensation is preferably performed in aqueous acetonitrile and the product is precipitated from the alkaline reaction mixture by the addition of water. The products that can be produced according to the process of the invention are known pharmaceutical active ingredients with anticonvulsive or antiepileptic action.

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Visp, Switzerland

David Laffan