Effects of Extended Aryl-Substituted Bisoxazoline Ligands in Asymmetric Synthesis - Efficient Synthesis and Application of 4,4′-Bis(1-Naphthyl)-, 4,4′-Bis(2-Naphthyl)- and 4,4′-Bis(9-Anthryl)-2,2′-isopropylidenebis(1,3-oxazolines)
作者:Hester L. van Lingen、Floris L. van Delft、Roy P. M. Storcken、Koen F. W. Hekking、Anouk Klaassen、Jan J. M. Smits、Patrycja Ruskowska、Jadwiga Frelek、Floris P. J. T. Rutjes
DOI:10.1002/ejoc.200500566
日期:2005.12
The steric influence of extended aryl substituents on 2,2′-bis(1,3-oxazoline) ligands was investigated in a series of asymmetric catalytic reactions such as Mukaiyama aldol and Michael reactions, hetero-Diels–Alder processes, and allylic alkylation reactions. 4,4′-(2-Naphthyl)- and 4,4′-(9-anthryl)-substituted isopropylidene-bridged 2,2′-bis(1,3-oxazolines) were synthesized and their enantioselective
The present invention related to a compound of the formula :
wherein R1 is hydrogen, isonitrile or an organic residue bonded through nitrogen ; R is hydrogen, alkyl ' which may be substituted, alkylthio in which sulfur atom may be oxidized or azido, or forms a double bond together with the adjacent carbon atom; provided that when R1 is an organic residue bonded through nitrogen, R is not hydrogen; R2 is carboxyl or a group derivable therefrom, and a salt thereof, and a method for producing the same.
The Compound (I) of the present invention has, among others, an excellent anitimicrobial activity and is useful as an antimicrobial agent, etc.
Hybrid Catalysis of 8-Quinolinecarboxaldehyde and Brønsted Acid for Efficient Racemization of α-Amino Amides and Its Application in Chemoenzymatic Dynamic Kinetic Resolution
The combination of 8-quinolinecarboxaldehyde and benzoic acid proved to be an effective catalyst system for the racemization of N-unprotected α-aryl- or α-alkyl-substituted α-amino amides. Application of this system to chemoenzymatic dynamic kineticresolution provided an efficient access to enantiomerically pure N-acetyl-α-amino amides in good to high yields.
Antibiotic isoxazole derivatives, their production and use
申请人:Takeda Chemical Industries, Ltd.
公开号:EP0191989A1
公开(公告)日:1986-08-27
The compounds of the formula:
wherein R1 is amino or an organic residue bonded through nitrogen; R2 is carboxy or a group derivable therefrom; X is hydrogen, methoxy or formylamino, provided that when R' is acetylamino or amino and X is hydrogen, R2 is not paranitrobenzyloxycarbonyl or benzhydryloxycarbonyl or salts thereof exhibit excellent antimicrobial activity, and are utilized as antimicrobial agents.
The compound represented by the formula:
where R' stands for amino or an organic residue bonded through nitrogen; R2 stands for carooxyl ora group derivable therefrom; R3, R4, R5, R6, R7 and R8 independently stand for hydrogen or an organic residue, including the case where R5 or R6 forms a chemical bond or a ring with R7 or R8: X stands for hvdrogen, methoxy or formylamino; or a salt thereof, pro- duceaole by the present method. exnibits excellent antimicrobial activity, and is utilized as antimicrobial agents.