Crown Ether-Derived Chiral BINOL: Enantioselective Michael Addition of Alkenyl Boronic Acids to α,ß-Unsaturated Ketones.

A new class of aza-crown ether-derived chiral BINOL catalysts were designed, synthesized, and applied in the asymmetric Michael addition of alkenylboronic acids to α,ß-unsaturated ketones. It was found that introducing aza-crown ethers to the BINOL catalyst could achieve apparently higher enantioselectivity than a similar BINOL catalyst without aza-crown ethers did, although the host-guest complexation of alkali ions by the aza-crown ethers could not further improve the catalysis effectiveness. Under mediation of the aza-crown ether-derived chiral BINOL and in the presence of a magnesium salt, an array of chiral γ,δ-unsaturated ketones were furnished in good enantioselectivities (81-95% ees).

Self-assembly of chiral BINOL cages via imine condensation.

Condensation of an (S)- or (R)-BINOL-derived dialdehyde and tris(2-aminoethyl)amine produced chiral [2+3] imine cages, which were further reduced to furnish more stable chiral amine cages and applied in the enantioselective recognition of (1R,2R)- and (1S,2S)-1,2-diaminocyclohexane.

Chiral Metallacycles as Catalysts for Asymmetric Conjugate Addition of Styrylboronic Acids to α,ß-Enones.

Introducing self-assembly strategies into the construction of catalysts has been proven to have great advantages in asymmetric catalysis. We constructed two chiral metalla-triangles by highly efficient coordination-driven self-assembly from a chiral 3,3'-dipyridyl-substituted BINOL donor. They were successfully applied in asymmetric conjugate addition of a series of α,ß-unsaturated ketones with trans-styrylboronic acids. The use of these metalla-triangles as supramolecular catalysts is obviously conducive to the enhancement of catalytic activity and stereoselectivity in the presented addition reactions. Under induction of the chiral metalla-triangles, an array of α,ß-enones were converted to chiral γ,δ-unsaturated ketones in medium to quantitative yields (40-98%) with high enantioselectivities (87-96% ee).

[Evaluation of the clinical efficacy and the safety of salmeterol/fluticasone propionate accuhaler compared to budesonide turbuhalar in the control of adult asthma].

OBJECTIVE: To evaluate the efficacy and the safety of low dose salmeterol/fluticasone (SM/FP) combination therapy as compared to morate dose of budesonide (BUD) in the management of adult asthma. METHODS: A multicentre, randomised, open-label, parallel-group, 6-week treatment study was conducted. 398 patients (18 - 70 years) were given SM/FP (50/100 microg) twice daily via Accuhaler or BUD 400 microg twice daily via Turbuhaler. RESULTS: The morning and the evening peak expiratory flow (PEF) measurements both increased significantly (P < 0.01) in the SM/FP group, and the increase was greater than that in the BUD group. The significant benefit of SM/FP was evident from the first week. SM/FP led to a more significant reduction in the use of rescue medication and in the day- and night-time asthma symptom scores, as compared to budesonide. Both treatments were well tolerated, and the adverse reactions showed no significant difference between the two groups. CONCLUSIONS: Combination use of low doses of SM/FP is a better choice for the control of asthma. The addition of a low-dose long-acting beta(2) agonist is superior to the simple increase of the dosage of inhaled corticosteroids.