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Review: 49 refs. [ABSTRACT FROM AUTHOR]

Review: recent methodologies for the simultaneous formation of C-CF3 and C-C or C-heteroatom bonds by formal addition reactions to alkenes; 70 refs. [ABSTRACT FROM AUTHOR]

Review: 139 refs. [ABSTRACT FROM AUTHOR]

Reaction of cyclic β-diketones with aliphatic aldehydes provides an efficient access towards disubstituted chromenones, e.g. (III), (V) and (VII). [ABSTRACT FROM AUTHOR]

The asymmetric cyclization of cyclic β-diketones with α,β-unsaturated aldehydes is efficiently catalyzed by diarylprolinol silyl ethers to afford hydroxychromenone derivatives, e.g. (III), in good yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

Epoxide-opening cascades offer the potential to construct complex polyether natural products expeditiously and in a manner that emulates the biogenesis proposed for these compounds. Herein we provide a full account of our development of a strategy that addresses several important challenges of such cascades. The centerpiece of the method is a trimethylsilyl (SiMe3) group that serves several purposes and leaves no trace of itself by the time the cascade has come to an end. The main function of the SiMe3 group is to dictate the regioselectivity of epoxide opening. This strategy is the only general method of effecting endo-selective cascades under basic conditions. [ABSTRACT FROM AUTHOR]

The reaction affords α-aryl-βtrifluoromethylamides with a quaternary stereocenter or trifluoromethylated oxindoles from the N-aryl or N-alkyl substrates of the types (I) or (X), respectively. [ABSTRACT FROM AUTHOR]

Two series of enantiopure azobenzenes with a p-tolylsulfoxide at the ortho or meta position with respect to the azo group, have been regioselectively synthesized. Both can act as enantiopure molecular switches showing different structural features owing to the presence of the stereogenic sulfur. The photoisomerization process, studied by UV-vis, circular dichroism (CD), NMR, and chiral HPLC evidenced a double role of the sulfoxide. A transfer of chirality from the sulfoxide to the azo system was observed by CD in both cis and trans-isomers of the meta sulfinyl derivatives 3, whereas this perturbation was evident for the ortho sulfinyl series 7 only in the cis isomer. The NMR study evidenced that the s-cis rigid conformation of the bisaromatic sulfoxide was fixing a different orientation of the overall system in each series both in the trans and cis isomers, by forcing a final U-shaped structure in cis-3 and an S-shaped structure in cis-7. Very different values of specific optical rotations were measured in both trans and cis isomers, also reflecting the existence of distinct chiral entities in the photostationary states. The easy and reversible changes occurring between different contormational states could find applications in the photocontrol of several molecular switches. [ABSTRACT FROM AUTHOR]

Cyanide is a hazardous and detrimental chemical that causes the inactivation of the respiration system through the inactivation of cytochrome c oxidase. Because of the limitation in the number of cyanide-degrading enzymes, there is a great demand to design and introduce new enzymes with better functionality. This study developed an integrated method of protein-homology-modelling and ligand-docking protein-design approaches that reconstructs a better active site from cyanide hydratase (CHT) structure. Designing a mutant CHT (mCHT) can improve the CHT performance. A computational design procedure that focuses on mutation for constructing a new model of cyanide hydratase with better activity was used. In fact, this study predicted the three-dimensional (3D) structure of CHT for subsequent analysis. Inducing mutation on CHT of Trichoderma harzianum was performed and molecular docking was used to compare protein interaction with cyanide as a ligand in both CHT and mCHT. By combining multiple designed mutations, a significant improvement in docking for CHT was obtained. The results demonstrate computational capabilities for enhancing and accelerating enzyme activity. The result of sequence alignment and homology modeling show that catalytic triad (Cys-Glu-Lys) was conserved in CHT of Trichoderma harzianum. By inducing mutation in CHT structure, MolDock score enhanced from −18.1752 to −23.8575, thus the nucleophilic attack can occur rapidly by adding Cys in the catalytic cavity and the total charge of protein in pH 6.5 is increased from −6.0004 to −5.0004. Also, molecular dynamic simulation shows a stable protein-ligand complex model. These changes would help in the cyanide degradation process by mCHT. [ABSTRACT FROM AUTHOR]

Two highly stereoselective radical-mediated syntheses of densely functionalized indanes and dibenzocycloheptadienes from ortho-vinyl- and ortho-vinylaryl-substituted N-(arylsulfonyl)-acrylamides, respectively, are presented. [ABSTRACT FROM AUTHOR]

A variety of N-(arylsulfonyl)acrylamides are used as substrates for the title reactions. [ABSTRACT FROM AUTHOR]

Bu4NI is able to activate Togni reagent (II) to generate a highly reactive iodine (III) species, which smoothly reacts with alkenes to form a new C-CF3 bond. [ABSTRACT FROM AUTHOR]