结构结构多样的γ-和δ-内酯是利用粘质沙雷氏菌(Sm CR V4)中的一种工程化羰基还原酶有效地立体选择性合成的。与野生型酶相比,Sm CR V4表现出更高的活性(最高达500倍)和对14种γ-/δ-酮酸和酯的热稳定性,催化效率提高了110倍(k cat / K m)对4-氧代十二烷甲酸甲酯。证明了烷基和芳香族γ-和δ-内酯的制备合成,其ee率为95%-> 99%,收率为78%-90%。最高时空产量为1175 g L -1 d -1,达到了(R)-γ-癸内酯
A Convenient Approach to Enantioenriched
Cyclopropanes Bearing Electron-Withdrawing Functionalities
作者:Henryk Krawczyk、Katarzyna Wąsek、Jacek Kędzia
DOI:10.1055/s-0028-1088034
日期:——
1,2-Disubstituted cyclopropanes with different electron-withdrawing groups were accessed stereospecifically from similarly functionalized γ-hydroxy-α,β-unsaturated compounds.
An enantioselective access to (−)-indolizidine alkaloids167B, 209D, 239AB, 195B and (−)-monomorine from a new chiral synthon is described. The use of (S)-3-(Cbz-amino)-4-(tert-butyldimethylsilyloxy)butanal, obtained from l-aspartic acid, has provided efficient access of the indolizidine frame work through a Horner–Wadsworth–Emmons reaction and reductive cyclization as the key steps.
A simple and efficient synthesis of Hagen's gland lactones was achieved using a sequential α-aminoxylation/oxa-Michael approach in a highly diastereoselective manner with assignment of relative configurations. This method was found to be applicable to the synthesis of various other isomers of Hagen's gland lactones.
The present invention relates to a compound of the Formula (I)):
or pharmaceutically acceptable salt thereof, wherein the symbols are as defined in the specification; a pharmaceutical composition comprising the same, a method for treating or preventing viral infections, inflammation, dry eye, central nervous disorders, cardiovascular diseases, cancer, obesity, diabetes, muscular dystrophy, and hair loss.
Enantioselective Synthesis of <i>syn</i>/<i>anti</i>-1,3-Amino Alcohols via Proline-Catalyzed Sequential α-Aminoxylation/α-Amination and Horner−Wadsworth−Emmons Olefination of Aldehydes
作者:Vishwajeet Jha、Nagendra B. Kondekar、Pradeep Kumar
DOI:10.1021/ol100856u
日期:2010.6.18
A novel and general method for asymmetric synthesis of both syn/anti-1,3-amino alcohols is described. The method uses proline-catalyzed sequential alpha-aminoxylation/alpha-amination and Horner-Wadsworth-Emmons (HWE) olefination of aldehydes as the key step. By using this method, a short synthesis of a bioactive molecule, (R)-1-((S)-1-methylpyrrolidin-2-yl)-5-phenylpentan-2-ol, is also accomplished.