The TiCl4-catalyzed reaction of aromatic carbonyl compounds with (dialkylamino)dimethylsilanes gave tertiary amines in moderate to high yields. The reductive amination of aliphatic aldehydes was effectively catalyzed by ZnI2. Methyl N-(dimethylsilyl)carbamate as well could be used for reductive amination of carbonyl compounds in the presence of Ph3CClO4.
Xanthine derivatives, the preparation thereof and their use as pharmaceutical compositions
申请人:——
公开号:US20020198205A1
公开(公告)日:2002-12-26
The present invention relates to substituted xanthines of general formula
1
wherein R
1
to R
4
are defined as in claim 1, the tautomers and the stereoisomers thereof, mixtures thereof, the prodrugs and the salts thereof which have valuable pharmacological properties, particularly an inhibiting effect on the activity of the enzyme dipeptidylpeptidase-IV (DPP-IV).
LIGAND COMPOUND, CATALYST SYSTEM FOR OLEFIN OLIGOMERIZATION, AND METHOD FOR OLEFIN OLIGOMERIZATION USING THE SAME
申请人:LG CHEM, LTD.
公开号:US20160207946A1
公开(公告)日:2016-07-21
This disclosure relates to a ligand compound, a catalyst system for olefin oligomerization, and a method for olefin oligomerization using the same. The catalyst system for olefin oligomerization according to the present invention has excellent catalytic activity, and yet, exhibits high selectivity to 1-hexene or 1-octene, thus enabling more efficient preparation of alpha-olefin.
Xanthine derivatives,production and use thereof as medicament
申请人:——
公开号:US20040077645A1
公开(公告)日:2004-04-22
The present invention relates to substituted xanthines of general formula
1
wherein R
1
to R
4
are defined as in claim 1, the tautomers and the stereoisomers thereof, mixtures thereof, the prodrugs and the salts thereof which have valuable pharmacological properties, particularly an inhibiting effect on the activity of the enzyme dipeptidylpeptidase-IV (DPP-IV).
XANTHINE DERIVATIVES, THE PREPARATION THEREOF AND THEIR USE AS PHARMACEUTICAL COMPOSITIONS
申请人:Himmelsbach Frank
公开号:US20060247226A1
公开(公告)日:2006-11-02
The present invention relates to substituted xanthines of general formula
wherein R
1
to R
4
are defined as in claim 1, the tautomers and the stereoisomers thereof, mixtures thereof, the prodrugs and the salts thereof which have valuable pharmacological properties, particularly an inhibiting effect on the activity of the enzyme dipeptidylpeptidase-IV (DPP-IV).