- PROCESS FOR THE PREPARATION OF PYRAZOLE CARBOXYLIC ACID DERIVATIVES
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The present invention relates to a novel process for the preparation of a pyrazole carboxylic acid derivative of the formula wherein R1 is C1-7-alkyl and R3 is C1-7-alkyl which is optionally substituted with halogen or C1-4-alkoxy. The pyrazole carboxylic acid derivative of the formula I can be used as building block in the preparation of pharmaceutically active principles e.g. for compounds acting as phosphodiesterase (PDE) inhibitors, particularly PDE10 inhibitors. PDE10 inhibitors have the potential to treat psychotic disorders like schizophrenia.
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- PROCESS FOR THE PREPARATION OF PYRAZOLE CARBOXYLIC ACID DERIVATIVES
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The present invention relates to a novel process for the preparation of a pyrazole carboxylic acid derivative of the formula (I) wherein R1 is C1-7-alkyl and R3 is C1-7-alkyl which is optionally substituted with halogen or C1-4-alkoxy. The pyrazole carboxylic acid derivative of the formula I can be used as building block in the preparation of pharmaceutically active principles, e.g. for compounds acting as phosphodiesterase (PDE) inhibitors, particularly PDE10 inhibitors. PDE10 inhibitors have the potential to treat psychotic disorders like schizophrenia (Int. Patent Publication WO 2011/117264). A synthetic approach to the pyrazole carboxylic acid derivative of the formula I has been described in scheme 3 of the Int. Patent Publication WO 2011/117264 applying a method disclosed in Hanzlowsky et al, J. Heterocyclic Chem. 2003, 40(3), 487-489. However, under the acid-catalyzed cyclocondensation conditions described, besides of the desired isomer, also a substantial amount of the undesired N-1 substituted isomer was formed. In many cases, especially on larger scale, this undesired isomer is the major product in the reaction mixture with ratios of up to 70:30 in favor of the undesired isomer, leading to isolated yields of ca. 30% of the undesired isomer, along with ca. 25% of the desired isomer.
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Page/Page column 13; 14
(2014/03/22)
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- NOVEL IMIDAZOPYRIDINES
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The invention is concerned with novel imidazopyridine derivatives of formula (I) wherein R1, R2, R3, R4, R5 and A are as defined in the description and in the claims, as well as physiologically accept
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Page/Page column 15
(2011/04/18)
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- IMIDAZOPYRIMIDINE DERIVATIVES
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The invention is concerned with novel imidazopyrimidine derivatives of formula (I) wherein R1, R2 and R8 are as defined in the description and in the claims, as well as physiologically acceptable salts and esters thereof. These compounds inhibit PDE10A and can be used as pharmaceuticals.
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Page/Page column 24-25
(2011/10/12)
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- N-(IMIDAZOPYRIMIDIN-7-YL)-HETEROARYLAMIDE DERIVATIVES AND THEIR USE AS PDE10A INHIBITORS
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The invention is concerned with novel imidazopyrimidine derivatives of formula (I) wherein R1, R2 and R8 are as defined in the description and in the claims, as well as physiologically acceptable salts and esters thereof. These compounds inhibit PDEIOA and used as medicaments.
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Page/Page column 69
(2011/10/13)
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- IMIDAZOPYRIDINE OR IMIDAZOPYRIMIDINE DERIVATIVES AS PHOSPHODIESTERASE 10A INHIBITORS
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The invention is concerned with novel imidazopyridine derivatives of formula (I) wherein R1, R2, R3, R4, R5 and A are as defined in the description and in the claims, as well as physiologically accept
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Page/Page column 40-41
(2011/04/24)
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