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A full account of our studies toward reverse-prenylated indole alkaloids that contain a bicyclo[2.2.2]core is described. A divergent route is reported which has resulted in the synthesis of preparaherquamide, (+)-VM-55599, and premalbrancheamide. An intramolecular Dieckmann cyclization between an enolate and isocyanate was used to forge the bicyclo[2.2.2]diazaoctane core that is characteristic of these molecules. The pentacyclic indole scaffold was constructed through a one-pot Hofmann rearrangement followed by Fischer indole synthesis. The utilization of our previously reported indole peripheral functionalization strategy also led to natural products including malbrancheamides B, C, stephacidin A, notoamides F, I and R, aspergamide B, and waikialoid A. Ultimately, the divergent route that we devised provided access to a wide range of prenylated indole alkaloids that are differently substituted on the cyclic amine core.

Trifluoromethyl-substituted arenes and heteroarenes are widely prevalent in pharmaceuticals and agrochemicals. As a result, the development of practical methods for the formation of aryl–CF3 bonds has become an active field of research. Over the past five years, transition-metal-catalyzed cross-coupling between aryl–X (X = halide, organometallic, or H) and various ‘CF3’ reagents has emerged as a particularly attractive approach to generating aryl– CF3 bonds. Despite many recent advances in this area, current methods generally suffer from limitations such as poor generality, harsh reaction conditions, the requirement for stoichiometric quantities of metals, and/or the use of costly CF3 sources. This Account describes our recent efforts to address some of these challenges by: (1) developing aryltrifluoromethylation reactions involving high oxidation state Pd intermediates, (2) exploiting AgCF3 for C–H trifluoromethylation, and (3) achieving Cu-catalyzed trifluoromethylation with photogenerated CF3•. 1 Introduction 2 Part 1. Aryltrifluoromethylation via High-Valent Palladium 3 Part 2. Aryltrifluoromethylation Using AgCF3 4 Part 3. Cu-Catalyzed Aryltrifluoromethylation with CF3• 5 Outlook [ABSTRACT FROM AUTHOR]

A mild and practical protocol for the copper-mediated trifluoromethylation of aryl and heteroaryl boronic acids using NaSO2CF3(Langlois’ reagent) and TBHP is described. The reaction proceeds at room temperature under ambient conditions, and the products can be readily purified by extraction or column chromatography. [ABSTRACT FROM AUTHOR]

Copper plays a dual role: to coordinate both the aryl and fluoride ligands and to serve as an oxidant generating the reactive Cu(III) key intermediate. [ABSTRACT FROM AUTHOR]

Various important (hetero)aromatic structural motifs are available under mild conditions. [ABSTRACT FROM AUTHOR]

This article describes the rational design of first generation systems for oxidatively induced Aryl-CF(3) bond-forming reductive elimination from Pd(II). Treatment of (dtbpy)Pd(II)(Aryl)(CF(3)) (dtbpy = di-tert-butylbipyridine) with NFTPT (N-fluoro-1,3,5-trimethylpyridinium triflate) afforded the isolable Pd(IV) intermediate (dtbpy)Pd(IV)(Aryl)(CF(3))(F)(OTf). Thermolysis of this complex at 80 °C resulted in Aryl-CF(3) bond-formation. Detailed experimental and computational mechanistic studies have been conducted to gain insights into the key reductive elimination step. Reductive elimination from this Pd(IV) species proceeds via pre-equilibrium dissociation of TfO(-) followed by Aryl-CF(3) coupling. DFT calculations reveal that the transition state for Aryl-CF(3) bond formation involves the CF(3) acting as an electrophile with the Aryl ligand serving as a nucleophilic coupling partner. These mechanistic considerations along with DFT calculations have facilitated the design of a second generation system utilizing the tmeda (N,N,N',N'-tetramethylethylenediamine) ligand in place of dtbpy. The tmeda complexes undergo oxidative trifluoromethylation at room temperature., (© 2011 American Chemical Society)

A(2A) adenosine receptor (A(2A)AR) antagonists are considered to be useful in cancer immunotherapy and vaccines and as potential drugs for the treatment of Parkinson's disease. To better understand the chemical features responsible for the recognition mechanism and the receptor-ligand interaction, we performed the molecular docking study using selective A(2A)AR antagonists and combined with a pharmacophore based virtual library screening. The putative binding mode for the antagonists served as the templates for pharmacophore modeling and a virtually generated library have been screened for novel A(2A)AR antagonist development.