Synthesis Of Chiral 2,3-dihydroflavonol Derivatives And The Key Intermediate Of Salinospoamide A

The development of efficient methods for the important chiral intermediates is significant in medicinal synthesis optically key chiral intermediates are among the most versatile buildingblocks for access to several natural products and pharmaceu ticals. This thesis synthsized important chiral intermediates and completed the following two aspects of the research:1.A series of chiral p-OMOM-α,β-epoxy ketone intermediate were prepared in one-pot reaction from the the aromatic aldehyde and ketone. In the presence of trifluoromethanesulfonic acid, p-OMOM-α,β-epoxyketones undergo decyclization and rearrangement to afford a series of chiral dihydroflavonol derivatives.(1).The results obtained showed that in a homogeneous system, the chiral catalyst [3-apmim] Cl-PLL possessed the good catalytic activity,the yield and optical purity were 85% and 89%.(2).In THF/H2O=3/1 solution system, trifluoromethanesulfonic acid catalyzed rearrangement of p-OMOM-α,β-epoxy ketone intermediate to afford dihydroflavonol with the yield 82% and optical purity 89%.(3).Chiral dihydroflavonol was synthesized in one-pot reaction from the the benzaldehyde and p-OMOM acetophenone, the yield and optical purity were 37.8% and 87%.(4). A series of chiral dihydroflavonol derivatives were synthesized with good reaction yield, which makes it possible to obtain ideal stereoselectivity with modified catalyst in two-step reaction.2. Proteasome inhibitors salinospoamide A intermediate was synthesized according to choose L-serine methyl ester hydrochloride as the starting material in 9 steps routine,which make it possible to prepare salinospoamide A derivatives rapidly and stably.