Several novel chiral thiazoline catalysts containing thiazoline, thiourea and proline were efficiently synthesized from commercially available L-cysteine. These ligands were subsequently applied to the asymmetric Mich...Several novel chiral thiazoline catalysts containing thiazoline, thiourea and proline were efficiently synthesized from commercially available L-cysteine. These ligands were subsequently applied to the asymmetric Michael reaction between cyclohexanone and various β-nitrostyrene. The result shows that the optimal catalyst for this reaction is ligand 18d, the organocatalyst with thiazoline, thiourea and chiral proline motif, which efficiently promotes the enantioselective conjugate addition of cyclohexanone to various nitroalkenes to yield the corresponding addition products in high to excellent yields with enantiomeric excess(e.e.) up to 95% and diastereoselectivity ratio(dr.) up to 99:1.展开更多
lbuprofen(IBU) and its derivatives are widely used m treating many diseases, such as depression, glome- rulonephritis, fever caused by common cold or influenza, and rheumatoid arthritis. While in clinical trials, IB...lbuprofen(IBU) and its derivatives are widely used m treating many diseases, such as depression, glome- rulonephritis, fever caused by common cold or influenza, and rheumatoid arthritis. While in clinical trials, IBU was found to have many side effects. To weaken and prevent these side effects, a derivative called ibupro- fen-l-acetoxyethyl ester was synthesized in this paper. The maximum concentration(Cmax) in a shorter time was com- pared with IBU at the same dose.展开更多
文摘Several novel chiral thiazoline catalysts containing thiazoline, thiourea and proline were efficiently synthesized from commercially available L-cysteine. These ligands were subsequently applied to the asymmetric Michael reaction between cyclohexanone and various β-nitrostyrene. The result shows that the optimal catalyst for this reaction is ligand 18d, the organocatalyst with thiazoline, thiourea and chiral proline motif, which efficiently promotes the enantioselective conjugate addition of cyclohexanone to various nitroalkenes to yield the corresponding addition products in high to excellent yields with enantiomeric excess(e.e.) up to 95% and diastereoselectivity ratio(dr.) up to 99:1.
文摘lbuprofen(IBU) and its derivatives are widely used m treating many diseases, such as depression, glome- rulonephritis, fever caused by common cold or influenza, and rheumatoid arthritis. While in clinical trials, IBU was found to have many side effects. To weaken and prevent these side effects, a derivative called ibupro- fen-l-acetoxyethyl ester was synthesized in this paper. The maximum concentration(Cmax) in a shorter time was com- pared with IBU at the same dose.