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An efficient enantioselective Michael addition of 2-naphthols to alkylideneindolenines generated in situ from arenesulfonylalkylindoles has been described. The protocol provides an efficient and convenient access to C-3 alkyl-substituted indole derivatives containing phenolic hydroxyl groups with high yields (up to 96%) and enantioselectivities (up to 98% ee) under mild conditions.

For the first time the highly stereoselective title Michael addition reaction is presented.

The present first Michael addition provides an easy and convenient approach to C-3 alkyl-substituted indole derivatives with high enantioselectivities whereas diastereoselectivity depends on the cyano substrate.

A series of difunctionalized 4-hydroxybenzaldehyde derivatives (I) is designed, synthesized, and evaluated as cholinesterase (AChE, BChE) inhibitors.

19 novel β-carbolines of type (I) with efficient DNA-binding capacity and potent cytotoxicity are prepared.

A series of thiosemicarbazones is designed, synthesized, and evaluated as mushroom tyrosinase inhibitor.

A series of hydroxy- or methoxy-substituted phenylmethylenethiosemicarbazones were designed, synthesized and evaluated as mushroom tyrosinase inhibitors. The results demonstrated that most of target compounds had remarkable inhibitory activities on mushroom tyrosinase. Interestingly, compound 2h was found to be the most potent tyrosinase inhibitor with IC50 value of 0.18 μM. The possible interaction mode between compound 2h and tyrosinase was proposed. In addition, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of select compounds (IC50

An efficient FeCl3-catalyzed substitution reaction of propargylic acetates with enoxysilanes under mild conditions to afford corresponding γ-alkynyl ketones has been developed. The substitution reaction is followed by a TsOH-catalyzed cyclization without purification of the γ-alkynyl ketone intermediates, offering a straightforward synthetic route to tri- or tetrasubstituted furans.

Six rigid-body parameters (Shift, Slide, Rise, Tilt, Roll, Twist) are commonly used to describe the relative displacement and orientation of successive base pairs in a nucleic acid structure. The present work adapts this approach to describe the relative displacement and orientation of any two planes in an arbitrary moleculespecifically, planes which contain important pharmacophore elements. Relevant code from the 3DNA software package (Nucleic Acids Res. 2003, 31, 5108−5121) was generalized to treat molecular fragments other than DNA bases as input for the calculation of the corresponding rigid-body (or “planes”) parameters. These parameters were used to construct feature vectors for a fuzzy relational clustering study of over 700 conformations of a flexible analogue of the dopamine reuptake inhibitor, GBR 12909. Several cluster validity measures were used to determine the optimal number of clusters. Translational (Shift, Slide, Rise) rather than rotational (Tilt, Roll, Twist) features dominate clusterin...

A novel and efficient procedure for the synthesis of γ-alkynyl ketones by the nucleophilic substitution of propargylic acetates with enoxysilanes in the presence of a catalytic amount of Copper(II) triflate, has been developed. The substitution reaction can be followed by a 4-toluenesulfonic acid-catalyzed cyclization without purification of the γ-alkynyl ketone intermediates, offering a straightforward synthetic route to polysubstituted furans.

The BiCl3‐catalyzed reaction of pyrroles with electron‐deficient olefins generated the corresponding Michael adducts in high yields.

A new eunicellin-type diterpenoid, vigulariol (1), has been isolated from the sea pen Vigularia juncea. Metabolite 1 has been obtained previously as a side product from a chemical reaction; however...

A series of alpha- and beta-1-C-alkyl-1-deoxynojirimycin derivatives was prepared and evaluated as glycosidase inhibitors. Biological assays showed a marked dependence of the selectivity and potency of the inhibitors upon the position of the alkyl chain (alpha-1-C-, beta-1-C- or N-alkyl derivatives). In addition, the efficiency of alpha-1-C-alkyl-1-deoxynojirimycin derivatives as intestinal isomaltase inhibitors increases with the length of the alkyl chain. The strongest inhibition was found for alpha-1-C -nonyl-1-deoxynojirimycin with an IC50=3.5 nM (25x more potent inhibitor than the shorter chain homologue carrying a C8 chain). These results demonstrate that subtle changes in the aglycon fragment may result in remarkable enzyme specificity.