Regiochemically Flexible Substitutions of Di-, Tri-, and Tetrahalopyridines: The Trialkylsilyl Trick
摘要:
2,4-Difluoropyridine, 2,4-dichloropyridine, 2,4,6-trifluoropyridine, 2,4,6-trichloropyridine and 2,3,4,6-tetrafluoropyridine react with standard nucleophiles exclusively at the 4-position under halogen displacement. However, the regioselectivity can be completely reversed if a trialkylsilyl group is introduced in the 5-position of the 2,4-dihalopyridines or in the 3-position of the 2,4,6-trihalopyridines or 2,3,4,6-tetrahalopyridine. Then only the halogen most remote from the bulky silyl unit (at the 2-position in the case of the 2,4-halopyridines, at the 6-position with the other substrates) gets involved in the exchange process. After removal of the silyl protective group the nucleophile is invariably found to occupy the nitrogen-neighboring position.
The present invention relates to compounds of formula I,
wherein A, R
1
to R
7
are defined in the description, and to pharmaceutically acceptable salts thereof. The present invention also relates to the manufacture of such compounds or their pharmaceutically acceptable salts, pharmaceutical compositions containing them and their use as medicaments for the treatment and/or prophylaxis of diseases which can be treated with HDL-cholesterol raising agents, such as dyslipidemia, atherosclerosis and cardiovascular diseases.
[EN] N-PYRIDIN-3-YL OR N-PYRAZIN-2-YL CARBOXAMIDES<br/>[FR] N-PYRIDIN-3-YL- OU N-PYRAZIN-2-YL-CARBOXAMIDES
申请人:HOFFMANN LA ROCHE
公开号:WO2012049190A1
公开(公告)日:2012-04-19
The present invention relates to compounds of the formula I wherein A, R1 to R7 are defined in the description, and to pharmaceutically acceptable salts thereof, their manufacture, pharmaceutical compositions containing them and their use as medicaments for the treatment and/or prophylaxis of diseases which can be treated with HDL-cholesterol raising agents, such as particularly dyslipidemia, atherosclerosis and cardiovascular diseases.
The present invention is directed to a process for making 2-substituted pyridopyrimidones. In particular, 2-substituted pyridopyrimidones are made through the single step reaction of suitable acid derivatives with desired derivatives of amidines.
[EN] RADIOLABELLED FLUMAZENIL DERIVATIVES<br/>[FR] DÉRIVÉS RADIOMARQUÉS DE FLUMAZÉNIL
申请人:GE HEALTHCARE LTD
公开号:WO2012131037A1
公开(公告)日:2012-10-04
A novel 18F- labelled compound suitable for use as a PET tracer for imaging GABA receptors is provided as well as a precursor compound for use in its synthesis and methods for its preparation. Also disclosed herein is an in vivo imaging method comprising administration of said 18F- labelled compound, which finds use in the diagnosis of conditions in which expression of the GABAA receptor is abnormal, or in the monitoring of such conditions.
The present invention relates to compounds of formula I,
wherein A, R1 to R7 are defined in the description, and to pharmaceutically acceptable salts thereof. The present invention also relates to the manufacture of such compounds or their pharmaceutically acceptable salts, pharmaceutical compositions containing them and their use as medicaments for the treatment and/or prophylaxis of diseases which can be treated with HDL-cholesterol raising agents, such as dyslipidemia, atherosclerosis and cardiovascular diseases.