Lonza Ag

Lonza Inc.

Rudolf Fuchs

John McGarrity

Walter Brieden

Jean-Paul Roduit

Martin Eyer

Dominique Michel

Peter Chen

Andre Mueller

Johannes Hoffner

Felix Spindler

Stefan Hildbrand

Johannes Bartek

A process is disclosed for the preparation of a compound of formula and/or an addition salt of a proton acid, wherein Rand Rindependently represent alkyl, cycloalkyl, aryl or aralkyl, each aryl or aralkyl being optionally further substituted with alkyl, alkoxy and/or halogen.

Process for the preparation of N-monosubstituted &#x3b2;-amino alcohols

A process is disclosed for the preparation of a compound of formula and/or an addition salt of a proton acid, wherein Rand Rindependently represent alkyl, cycloalkyl, aryl or aralkyl, each aryl or aralkyl being optionally further substituted with alkyl, alkoxy and/or halogen. The process involves reacting a mixture comprising a methyl ketone of formula and a compound of formula HN&#x2014;R(V) and/or an addition salt of proton acid, and formaldehyde in the presence of a solvent selected from the group consisting of water, aliphatic alcohols, cycloaliphatic alcohols and mixtures thereof, and optionally a proton acid to afford a &#x3b2;-amino ketone of formula and/or an addition salt of a proton acid, and reducing the carbonyl group of said &#x3b2;-amino ketone to afford a compound of formula I, and/or an addition salt of a proton acid

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Method of producing 3-aminoalkanoic acid esters

Method for producing alkoxy malonic acid dinitriles

A process for preparing alkoxypyrazine derivatives of the general formula:

Process for preparing alkoxypyrazine derivatives

1,4,5,6-tetrahydropyrazine-2-carboxamides of formula: wherein R.sup.1 is hydrogen, alkyl, cycloalkyl or arylalkyl; R.sup.2 is alkyl, aryl, or arylalkyl and R.sup.3, R.sup.4 and R.sup.5 are hydrogen, acyl, aryl or arylalkyl or R.sup.2 forms an alicyclic system with R.sup.3 or R.sup.4 and the adjacent carbon atom(s), R.sup.6 being hydrogen or a group of formula R.sup.7 --C(.dbd.O)-- wherein R.sup.7 is hydrogen or alkyl. These compounds can be used in the production of piperazine carboxamides.

1,4,5,6-tetrahydropyrazine-2-carboxamides

A process for preparing alkoxypyrazine derivatives of the general formula: ##STR1## These alkoxypyrazine derivatives are obtained by reacting a glyoxal derivative of the general formula: ##STR2## and an aminomidiate of the general formula: ##STR3## The alkoxypyrazine derivatives are important intermediates for preparing pharmaceutically active compounds.

A novel process for the preparation of malononitrile which involves subjecting a (2-cyano-N-alkoxy)acetimidoyl halide to a high-temperature treatment.

Process for the preparation of malononitrile

A process for preparing 3-alkoxy-5-alkylpyrazin-2-amines of the general formula: ##STR1## wherein R.sup.1 is a C.sub.1-4 -alkyl group or an aryl group and R.sup.2 is a C.sub.1-4 -alkoxy group or an aryloxy group, starting either from aminomalononitrile or from aminoacetonitrile.

Process for preparing 3-alkoxy-5-alkypyrazin-2-amines

A novel process for the preparation of malononitrile, which involves subjecting an isonitrile, optionally in the presence of a nitrile, to a high-temperature treatment.

Optically active piperazine-2-carboxylic acid derivatives of the general formula: ##STR1## in which X is alkoxy or a (substituted) amino group, are prepared by asymmetric hydrogenation of the corresponding pyrazinecarboxylic acid derivatives, catalyzed by optically active rhodium complexes. The compounds of the formula I are intermediates for the preparation of pharmaceutical active substances, for example, HIV protease inhibitors.

Process for the preparation of optically active piperazine-2-carboxylic

Process for the production of 1,4,5,6-tetrahydropyrazine-2-carboxylic

Optically active piperazine-2-carboxylic acid derivatives of the general formula: ##STR1## wherein R.sup.1 and R.sup.2 are inter alia hydrogen, alkyl or acyl and X is alkoxy or a (substituted) amino group, are prepared by asymmetric hydrogenation of the corresponding 1,4,5,6-tetrahydropyrazines, catalyzed by optically active rhodium, ruthenium or iridium complexes. The compounds of the Formula 1 are intermediates for the preparation of pharmaceutical active ingredients, for example, HIV protease inhibitors.

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Sion, Switzerland

Rudolf Fuchs