Macrolactonizations in the Total Synthesis of Natural Products

In 2003, bortezomib, a first-in-class therapeutic, gained approval from the US Federal Drug Administration for the treatment of relapsed multiple myeloma and mantle cell lymphoma. Approval in the UK, for multiple myeloma, followed in 2006. Bortezomib contains a boronic acid, a functional group that has become increasingly more commonplace within the medicinal chemistry literature. The introduction of this drug has sparked a renewed interest in the investigation of boronic acids as drugs for a wide range of diseases. This review will guide the reader through the most recent developments in this field, by considering in turn, the biological target's amenable to the action of boronic acids.

Boronic acids in medicinal chemistry: anticancer, antibacterial and antiviral applications

The role of 1,3-dithianes in natural product synthesis

Products A. Parenty,† X. Moreau,†,§ Gilles Niel,‡ and J.-M. Campagne*,†,‡ †Institut de Chimie des Substances Naturelles, Avenue de la Terrasse, F-91198 Gif sur Yvette, France Institut Lavoisier de Versailles, UMR CNRS 8180, Universite ́ de Versailles-Saint-Quentin-en-Yvelines, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France ‡Institut Charles Gerhardt, UMR5253, Ecole Nationale Supeŕieure de Chimie, 8 rue de l’Ecole Normale, F-34296 Montpellier, France

Update 1 of: macrolactonizations in the total synthesis of natural products.

Efficient total syntheses of the C2-symmetric (−)-cylindrocyclophanes A and F (1a and 1f) have been achieved. The initial strategy featured the use of a common advanced intermediate to assemble in stepwise fashion the required macrocycle of 1f, exploiting in turn a Myers reductive coupling followed by ring-closing metathesis. In a second-generation strategy, a remarkable cross olefin metathesis dimerization cascade was discovered and exploited to assemble the requisite [7,7]-paracyclophane macrocycles of both 1a and 1f from dienyl monomers. The successful syntheses also featured the effective use of the Danheiser annulation to construct substrates for both the Myers reductive coupling and the metathesis dimerizations strategies. Finally, the Kowalski two-step chain homologation of esters to siloxyalkynes proved superior over the original one-step protocol.

Total Synthesis of (−)-Cylindrocyclophanes A and F Exploiting the Reversible Nature of the Olefin Cross Metathesis Reaction

Total synthesis of aplasmomycin

Methods for the interconversion of protective groups. Transformation of mem ethers into isopropylthiomethyl ethers or cyanomethyl ethers

Synthetic studies on boron containing antibiotics

The preparation of two fragments containing the backbone of the antibiotic boromycin is described.

Steven P. Seitz

Papers

Total synthesis of aplasmomycin

Methods for the interconversion of protective groups. Transformation of mem ethers into isopropylthiomethyl ethers or cyanomethyl ethers

Synthetic studies on boron containing antibiotics

Total synthesis of aplasmomycin

Synthetic Studies on Boron Containing Antibiotics.