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Chromosome region maintenance 1 (CRM1) is the sole nuclear exporter of several tumor suppressor, a growth regulatory protein as an attractive cancer drug target. In the present work, a novel CRM1 degrader was discovered from newly synthesized α, β-unsaturated-δ-lactone based on a natural product Goniothalamin. It induces apoptosis of both MGC803 and HGC27 cell lines via degrading CRM1. Selective inhibition was observed for the proliferation of gastric cancer cell lines MGC803, HGC27 comparing to Human Gastric Mucosal Epithelial Cell Line (GES1). For the first time, CRM1 inhibitor or degrader inducing apoptosis in gastric carcinoma was investigated.

The scope and limitations of metal tetrafluoroborates have been studied for epoxide ring-opening reaction with amines, and Zn(BF4) 2?xH2O has been found to be a mild and efficient catalyst affording high yields under solvent-free conditions at rt with excellent chemo-, regio-, and stereoselectivities. The catalytic efficiency followed the order Zn(BF4)2?xH2O ? Cu(BF4)2?xH2O > Co(BF4) 2?6H2O ? Fe(BF4)2? 6H2O > LiBF4 for reactions with cyclohexene oxide and Zn(BF4)2?xH2O ? Co(BF4) 2?6H2O ? Fe(BF4)2? 6H2O > Cu(BF4)2?xH2O for stilbene oxide, but AgBF4 was ineffective. For reaction of styrene oxide with aniline, the metal tetrafluoroborates exhibited comparable regioselectivity (1:99-7:93) with preferential reaction at the benzylic carbon of the epoxide ring. A reversal of regioselectivity (91:1-69:31) in favor of the reaction at the terminal carbon of the epoxide ring was observed for reaction with morpholine. The regioselectivity was dependent on the electronic and steric factors of the epoxide and the pKa of the amine and independent of amine nucleophilicity. The role of the metal tetrafluoroborates is envisaged as "electrophile nucleophile dual activation" through cooperativity of coordination, charge-charge interaction, and hydrogen-bond formation that rationalizes the catalytic efficiency, substrate reactivity, and regioselectivity. The methodology was used for synthesis of cardiovascular drug metoprolol as racemic and enriched enantiomeric forms.

The kinetic resolution of 1-chloro-3-[4-(2-methoxyethyl)phenoxy]-2-propanol rac-4 with Novozym 435 and vinyl stearate, a key step in the gram-scale synthesis of (2S)-2-[[(2R)-2-hydroxy-3-[4-(2-methoxyethyl)phenoxy]propyl]amino]-1-butanol (R,S)-1 a potent antihypertensive agent currently under investigation, is reported here. Our approach differs from the previously reported synthesis, which involves a tedious and poorly effective fractional crystallization of (R,S)-1. This novel approach incorporates an enzymatic resolution for the efficient preparation of the oxirane precursor (R)-3. The two main advantages arising from this strategy are the high enantioselectivity of the enzymatic process and the facilitated recovery of the hydrophobic stearate intermediate (S)-5.

The ring opening of epoxides with nucleophiles such as TMSN3 and isopropylamine takes place enantioselectively in the presence of β- cyclodextrin under extremely mild conditions and the azido alcohols and amino alcohols are formed as (S)-isomers. (C) 1999 Published by Elsevier Science Ltd.

Kinetic resolution of (±)-aryl glycidyl ethers using (R,R)-salen Co(III)OAc and water provided enantiomerically pure arylglycidyl ether and 1-arylglycerol derivatives with high enantiomeric excess. Application of this approach to (S)-metoprolol has been d