Bayer Aktiengesellschaft

Bayer Cropscience Ag

Bayeraktiengesellschaft

Kai Van Laak

Peter Fey

Rudolf Schohe-Loop

Bodo Junge

Joachim Mittendorf

Heinrich Meier

Johannes Kaulen

Wolfram Sirges

Paul Naab

Jan-Bernd Lenfers

Detlef Wollweber

Jörn Stölting

Armin Heyn

Torsten Taschner

The present invention relates to a process for the preparation of compounds of the formula (I)by reacting compounds of the formula (II)in which

Method for producing 1,3-disubstituted 2-nitroguanidines

The invention relates to a process and intermediates for the preparation of enantiomerically pure cycloalkanoindolecarboxylic acids and azaindolecarboxylic acids and pyrimido&lsqb;1,2a&rsqb;indolecarboxylic acids and their activated derivatives, characterized in that the tolyl acetic acid is first esterified with a chiral alcohol, then diastereoselective substitution at &agr;-carbon atoms is carried out and this product is halogenated in the tolyl group and then reacted with appropriate cycloalkanoindoles, cycloalkanoazaindoles or pyrimido&lsqb;1,2a&rsqb;indoles. It is possible by this method to prepare specifically, in high purity, the enantiomerically pure carboxylic acids which are intermediates for valuable medicaments.

Process for the preparation of enantiomerically pure cycloalkano-indol -and azaindol -and pyrimido &lsqb;1,2A&rsqb;indolcarbocyclic acids and their activated derivatives

The present invention relates to a novel process for the preparation of N-methyl-N&prime;-nitroguanidine by reacting nitroguanidine with aqueous methylamine solution buffered by the addition of inorganic or organic acids.

Method for producing N-methyl-N&prime;-nitroguanidine

Method for production of 1,3-disubtituted 2-nitroguanidines

The invention relates to a process and intermediates for the preparation of enantiomerically pure cycloalkanoindolecarboxylic acids and azaindolecarboxylic acids and pyrimido�1,2a!indolecarboxylic acids and their activated derivatives, characterized in that the tolyl acetic acid is first esterified with a chiral alcohol, then diastereoselective substitution at .alpha.-carbon atoms is carried out and this product is halogenated in the tolyl group and then reacted with appropriate cycloalkanoindoles, cycloalkanoazaindoles or pyrimido�1,2a!indoles. It is possible by this method to prepare specifically, in high purity, the enantiomerically pure carboxylic acids which are intermediates for valuable medicaments.

Process for the preparation of enantiomerically pure cycloalkano-indol

The present invention relates to a new highly selective process for the preparation of enantiomerically pure halogeno-phenyl-substituted 1,4-dihydropyridine-3,5-dicarboxylic esters of the general formula (I) ##STR1## in which R.sup.1 to R.sup.3 have the meanings given in the description.

Highly selective process for the preparation of enantiomerically pure

This invention relates to benzolididene compounds of the formula ##STR1## in which R.sup.2 represents the radical ##STR2## in which R.sup.4 and R.sup.5 are identical or different and denote halogen, cyano, ethinyl, trifluoromethoxy, methylthio, nitro, trifluoromethyl or straight-chain or branched alkyl, alkenyl, alkinyl or alkoxy having up to 4 carbon atoms, and one of the substituents optionally represents hydrogen, or a salt thereof.

Pyrrolidine compounds and process of preparing

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Kö'ln, Germany

Kai Van Laak