Cyclization of 1,6-diynes promoted by stoichiometric Ga(III) halides produces vinyl halides in good to excellent yields. Under acidic conditions, initially formed iodocyclization products undergo in situ Friedel–Crafts cyclizations, giving access to iodoindenopyridines. Application of the vinyl halides in cross-coupling reactions has been explored, and mechanistic aspects of the cyclization are discussed.

New indoline alkaloid-type compounds which inhibit HCV production by infected hepatoma cells have been identified. These compounds, dimeric-type compounds of previously known inhibitors, display double digit nanomolar IC50 and EC50 values, with cytotoxicity CC50 indexes higher than 36 μM, thus providing ample therapeutic windows for further development of HCV drugs.

Diels−Alder cycloadditions of highly substituted cyclohexadienes derived from rhodium-mediated [2 + 2 + 2] cyclizations are reported. Reactive heterodienophiles, including singlet oxygen (1O2), 4-substituted-1,2,4-triazoline-3,5-diones (TADs), and aryl- and acylnitroso compounds were employed, yielding novel heterocyclic products.

The asymmetric syntheses of two anticancer natural products, candenatenins B and C, are described, leading to a revision of the originally assigned stereochemistries. The syntheses follow a Diels–Alder/retro-Diels Alder strategy using a chiral anthracene auxiliary to access both targets with 90% ee. The inherent structural qualities of the auxiliary allow for both regio- and diastereoselective transformations.

New small molecule inhibitors of HCV were discovered by screening a small library of indoline alkaloid-type compounds. An automated assay format was employed which allowed identification of dimerization inhibitors of core, the capsid protein of the virus. These compounds were subsequently shown to block production of infectious virus in hepatoma cells.

The Rh(I)-catalyzed inter- and intramolecular [2+2+2] cyclization of diynes with α,β-unsaturated enones proceeds with microwave promotion in good yields. This chemistry was applied to the synthesis of (−)-alcyopterosin I.

The chemistry of 5,6,7,8-tetrahydro-1,6-naphthyridine scaffolds, synthesized by intramolecular cobalt-catalyzed [2 + 2 + 2] cyclizations, has been exploited for library synthesis. Urea, amide, and sulfonamide formations were used in the synthesis of a 101-membered library. Screening of the library for antituberculosis activity revealed three lead compounds.

The platinum-mediated cyclopropane opening of [4 + 2 + 2] homo Diels–Alder cycloadducts has been probed through deuterium-labeling studies. The location of the deuterium in the olefinic products strongly supports an α-elimination mechanism that proceeds through a platinum carbene intermediate. Kinetic isotopic effects provide additional insights into the reaction mechanism, lending support to the platinum carbene formation as the rate-determining step.