Abstract: The invention relates to a process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R2, R3 and R4 are as defined in the specification, comprising the steps of a) catalytic asymmetric hydrogenation of an enamine of the formula wherein R1 is lower alkyl, in the presence of a transition metal catalyst containing a chiral diphosphane ligand, b) introduction of an amino protecting group Prot and c) amidation of the ester to form an amide of formula wherein R2, R3, R4 and Prot are as defined in the specification.

Abstract: This invention relates to a process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R1, R2, R3 and R4 are defined in the specification, comprising the optical resolution of an enamine of the formula wherein R1 is lower alkyl, in the presence of an optical active resolving agent to form an (S)-enamine salt of the formula wherein RCO2? is the conjugate base of the resolving agent.

Abstract: The invention relates to a process for the preparation of pyrido[2,1-a] isoquinoline derivatives of the formula wherein R2, R3 and R4 are as defined in the specification, comprising the steps of a) catalytic asymmetric hydrogenation of an enamine of the formula wherein R1 is lower alkyl, in the presence of a transition metal catalyst containing a chiral diphosphane ligand, b) introduction of an amino protecting group Prot and c) amidation of the ester to form an amide of formula wherein R2, R3, R4 and Prot are as defined in the specification.

Abstract: The invention relates to a process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R2, R3 and R4 are as defined in the specification, comprising the steps of a) catalytic asymmetric hydrogenation of an enamine of the formula wherein R1 is lower alkyl, in the presence of a transition metal catalyst containing a chiral diphosphane ligand, b) introduction of an amino protecting group Prot and c) amidation of the ester to form an amide of formula wherein R2, R3, R4 and Prot are as defined in the specification.

Abstract: This invention relates to a process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R1, R2, R3 and R4 are defined in the specification, comprising the optical resolution of an enamine of the formula wherein R1 is lower alkyl, in the presence of an optical active resolving agent to form an (S)-enamine salt of the formula wherein RCO2? is the conjugate base of the resolving agent.

Abstract: The present invention relates to a novel process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R2, R3 and R4 are each independently selected from the group consisting of hydrogen, halogen, hydroxy, lower alkyl, lower alkoxy and lower alkenyl, wherein lower alkyl, lower alkoxy and lower alkenyl may optionally be substituted by a group consisting of lower alkoxycarbonyl, aryl and heterocyclyl, and the pharmaceutically acceptable salts thereof. The pyrido[2,1-a]isoquinoline derivatives of the formula I are useful for the treatment and/or prophylaxis of diseases which are associated with DPP IV.

Abstract: This invention relates to a process for the preparation of pyrido[2,1-a] isoquinoline derivatives of the formula wherein R1, R2, R3 and R4 are defined in the specification, comprising the optical resolution of an enamine of the formula wherein R1 is lower alkyl, in the presence of an optical active resolving agent to form an (S)-enamine salt of the formula wherein RCO2? is the conjugate base of the resolving agent.

Abstract: The present invention relates to a novel process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R2, R3 and R4 are each independently selected from the group consisting of hydrogen, halogen, hydroxy, lower alkyl, lower alkoxy and lower alkenyl, wherein lower alkyl, lower alkoxy and lower alkenyl may optionally be substituted by a group consisting of lower alkoxycarbonyl, aryl and heterocyclyl, and the pharmaceutically acceptable salts thereof. The pyrido[2,1-a]isoquinoline derivatives of the formula I are useful for the treatment and/or prophylaxis of diseases which are associated with DPP IV.

Abstract: This invention relates to a process for the preparation of pyrido[2,1-a] isoquinoline derivatives of the formula wherein R1, R2, R3 and R4 are defined in the specification, comprising the optical resolution of an enamine of the formula wherein R1 is lower alkyl, in the presence of an optical active resolving agent to form an (S)-enamine salt of the formula wherein RCO2? is the conjugate base of the resolving agent.

Abstract: The invention relates to a process for the preparation of pyrido[2,1-a] isoquinoline derivatives of the formula wherein R2, R3 and R4 are as defined in the specification, comprising the steps of a) catalytic asymmetric hydrogenation of an enamine of the formula wherein R1 is lower alkyl, in the presence of a transition metal catalyst containing a chiral diphosphane ligand, b) introduction of an amino protecting group Prot and c) amidation of the ester to form an amide of formula wherein R2, R3, R4 and Prot are as defined in the specification.

Abstract: The invention is concerned with (S)-1-{[2-(5-Methyl-2-phenyl-oxazol-4-yl)-ethylamino]-acetyl}-pyrrolidine-2-carbonitrile mesylate and crystalline polymorphs of this compound. This compound and its polymorphic forms exhibits superior properties compared to the previously known compounds and can be used as medicament for the treatment of disorders which are associated with DPP-IV.

Abstract: This invention relates to a process of the preparation of the novel intermediate (S)-4-fluoromethyl-dihydro-furan-2-one of the formula and with its use for the manufacture of pyrido[2,1-a]isoquinoline derivatives of the formula which are useful for the treatment and/or prophylaxis of diseases which are associated with DPP IV.

Abstract: The present invention relates to a novel process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R2, R3 and R4 are each independently selected from the group consisting of hydrogen, halogen, hydroxy, lower alkyl, lower alkoxy and lower alkenyl, wherein lower alkyl, lower alkoxy and lower alkenyl may optionally be substituted by a group consisting of lower alkoxycarbonyl, aryl and heterocyclyl, and the pharmaceutically acceptable salts thereof. The pyrido[2,1-a]isoquinoline derivatives of the formula I are useful for the treatment and/or prophylaxis of diseases which are associated with DPP IV.

Abstract: The invention relates to a process for the preparation of pyrido[2,1-a] isoquinoline derivatives of the formula wherein R2, R3and R4 are as defined in the specification, comprising the steps of a) catalytic asymmetric hydrogenation of an enamine of the formula wherein R1 is lower alkyl, in the presence of a transition metal catalyst containing a chiral diphosphane ligand, b) introduction of an amino protecting group Prot and c) amidation of the ester to form an amide of formula wherein R2, R3, R4 and Prot are as defined in the specification.

Abstract: This invention relates to a process for the preparation of pyrido[2,1-a]isoquinoline derivatives of the formula wherein R1, R2, R3 and R4 are defined in the specification, comprising the optical resolution of an enamine of the formula wherein R1 is lower alkyl, in the presence of an optical active resolving agent to form an (S)-enamine salt of the formula wherein RCO2? is the conjugate base of the resolving agent.

Abstract: This invention relates to a process of the preparation of the novel intermediate (S)-4-fluoromethyl-dihydro-furan-2-one of the formula and with its use for the manufacture of pyrido[2,1-a]isoquinoline derivatives of the formula which are useful for the treatment and/or prophylaxis of diseases which are associated with DPP IV.

Abstract: The invention is concerned with (S)-1-{[2-(5-Methyl-2-phenyl-oxazol-4-yl)-ethylamino]-acetyl}-pyrrolidine-2-carbonitrile mesylate and crystalline polymorphs of this compound. This compound and its polymorphic forms exhibits superior properties compared to the previously known compounds and can be used as medicament for the treatment of disorders which are associated with DPP-IV.

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: The invention is concerned with a new process for the preparation of compounds of formula ##STR1## wherein R is hydrogen, lower alkyl, lower alkoxy, cycloalkyl, cycloalkenyl, cycloalkyl-lower alkyl, lower alkenyl, lower alkynyl, aryl, aryl-lower alkyl, heterocyclyl or heterocyclyl-lower alkyl; the lower alkyl, cycloalkyl, lower alkenyl, cycloalkenyl, lower alkynyl, aryl-lower alkyl, aryl and the heterocyclyl moieties being unsubstituted or substituted with at least one group selected from carboxy, amino, carbamoyl, nitro, cyano, lower alkyl, lower alkoxy, hydroxy, halogen, aminomethyl, mercapto, trifluoromethyl and trichloroethyl.The compounds prepared according to above mentioned process are useful in the preparation of cephem, isoxacephem and carbacephem derivatives.