Abstract: The present invention relates to a process for the preparation of a 4,5-diamino shikimic acid derivative of formula and pharmaceutically acceptable addition salts thereof wherein R1, R1? are independent of each other H or alkyl, R2 is an alkyl and R3, R4 are independent of each other H or an alkanoyl, with the proviso that not both R3 and R4 are H. 4,5-diamino shikimic acid derivatives of formula I, especially the (3R,4R,5S)-5-amino-4-acetylamino-3-(1-ethyl-propoxy)-cyclohex-1-ene-carboxylic acid ethyl ester and its pharmaceutically acceptable additional salts are potent inhibitors of viral neuraminidase.

Abstract: The present invention relates to a process for the preparation of a 4,5-diamino shikimic acid derivative of formula and pharmaceutically acceptable addition salts thereof wherein R1, R1? are independent of each other H or alkyl, R2 is an alkyl and R3, R4 are independent of each other H or an alkanoyl, with the proviso that not both R3 and R4 are H. 4,5-diamino shikimic acid derivatives of formula I, especially the (3R,4R,5S)-5-amino-4-acetylamino-3-(1-ethyl-propoxy)-cyclohex-1-ene-carboxylic acid ethyl ester and its pharmaceutically acceptable additional salts are potent inhibitors of viral neuraminidase.

Abstract: The invention provides a multistep process for preparing 1,2-diamino compounds and pharmaceutically acceptable addition salts thereof from 1,2-epoxides.

Abstract: The present invention is concerned with mixed anhydrides. The mixed anhydrides are prepared by adding an adjuvant base to a mixture of acid and reactive acid derivative. The mixed anhydrides play an role primarily in activating and coupling reactions.

Abstract: The present invention is concerned with an improved process for the manufacture of mixed anhydrides. The process comprises adding an adjuvant base to a mixture of acid and reactive acid derivative. It is especially suitable for use in the synthesis of peptides and/or for the manufacture of pharmaceutically active substances or corresponding intermediates.

Abstract: The invention provides a multistep process for preparing 1,2-diamino compounds of formula wherein R1, R1′, R2, R2′, R3 and R4 have the meaning given in the specification and pharmaceutically acceptable addition salts thereof, from 1,2-epoxides of formula wherein R1, R′, R2 and R2′ have the meaning given in the specification.

Abstract: The invention provides a multistep process for preparing 1,2-diamino compounds and pharmaceutically acceptable addition salts thereof from 1,2-epoxides.

Abstract: The present invention is concerned with an improved process for the manufacture of mixed anhydrides. The process comprises adding an adjuvant base to a mixture of acid and reactive acid derivative. It is especially suitable for use in the synthesis of peptides and/or for the manufacture of pharmaceutically active substances or corresponding intermediates.

Abstract: The invention provides a multistep synthesis for the preparation of 4,5-diamino shikimic acid derivatives of formula wherein R1, R2, R3 and R4 are defined in the specification, starting from furan. 4,5-Diamino shikimic acid derivatives are potent inhibitors of viral neuraminidase.

Abstract: The invention provides a multistep synthesis for the preparation of 4,5-diamino shikimic acid derivatives of formula 1

Abstract: A process for preparing a compound of formula (I) or a phamaceutically-acceptable salt thereof, comprising: 1) reacting a compound. of formula (III), in which R is a straight or branched chain alkyl having from one to four carbon atoms, with an alkali metal hydroxide in an aqueous medium at a temperature of about 80.degree. to 120.degree. C. and time of about 20 to 100 hours to form a reaction product; 2) cyclizing the reaction product of step 1) with formic acid and formaldehyde to form a formiate compound; and 3) neutralizing the formiate compound of step 2) with an aqueous base.

Abstract: A catalytic process for the manufacture of optically active compounds of the formula ##STR1## wherein R.sup.1 and R.sup.2 are alkyl, which is optionally interrupted by an O atom in a position other than the .alpha.-or .beta.-position, or optionally substituted benzyl,R.sup.3 is hydrogen, lower alkyl, optionally substituted benzyl, --CO--R.sup.4, --COOR.sup.4 or --CONR.sub.2.sup.4, andR.sup.4 is lower alkyl or aryl,comprising asymmetrically hydrogenating a compound of the formula ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 have the above significance, in the presence of a complex of an optically active, preferably atropisomeric, diphospine ligand with a metal of Group VIII.

Abstract: The invention relates to a novel process for producing a compound having the formula ##STR1## wherein R.sup.1, R.sup.2 and X are described herein, via corresponding .beta.-keto- and .beta.-hydroxy-.delta.-lactones, as well as novel intermediates which occur in the process.

Abstract: The invention relates to a novel process for producing a compound having the formula ##STR1## wherein R.sup.1, R.sup.2 and X are described herein, via wherein R corresponding .beta.-keto- and .beta.-hydroxy-.delta.-lactones, as well as novel intermediates which occur in the process.

Abstract: Methyl 4-dimethylamino-3,5-dimethoxybenzoate, an intermediate in the preparation of the antibacterially active aditoprim, is obtained from 4-amino-3,5-dibromobenzoic acid by replacement of the bromine atoms by methoxy groups and subsequent methylation.