2003

October 20, 2003

Constrained Peptidomimetics: Building Bicyclic Analogs of Pyrazoline Derivatives

Bin Liu, John D Brandt and Kevin D Moeller
Tetrahedron, 2003, 59 (43), 8515-8523

A synthetic route has been developed for incorporating pyrazoline derivatives as proline surrogates in constrained X-Pro peptidomimetics. The route allows for the synthesis of dipeptide building blocks having either a six or seven-membered-ring annulated onto the pyrazoline moiety, as well as for the asymmetric synthesis of analogs having substituents on N-terminal side of the building block.

 

August 15, 2003

Building Functionalized Peptidomimetics: New Electroauxiliaries and the Use of a Chemical Oxidant for Introducing N-Acyliminium Ions into Peptides

Haizhou Sun and Kevin D. Moeller
Org. Lett., 2003, 5 (18), pp 3189–3192

The removal of electroauxiliaries from peptide substrates with chemical oxidants has been examined as a method for inserting N-acyliminium ions into the peptides. To this end, it was found that both 4-methoxyphenyldimethylsilyl and 2,4-dimethoxyphenyldimethylsilyl electroauxiliaries were readily cleaved with the use of ceric ammonium nitrate. Of the two groups, the 2,4-dimethoxyphenyldimethylsilyl electroauxiliary was the most labile under the oxidative conditions. The oxidation reactions were shown to be compatible with the use of a solid-phase substrate.

 

December 5, 2002

Anodic Cyclization Reactions: the Total Synthesis of Alliacol A

John Mihelcic and Kevin D. Moeller
J. Am. Chem. Soc., 2003, 125 (1), pp 36–37

An anodic cyclization−Friedel Crafts alkylation strategy has been used to rapidly assemble the core ring system of alliacol A and to complete a formal total synthesis of the natural product. The anodic cyclization reaction was used to effect the coupling of a nucleophilic furan ring to the normally nucleophilic carbon of a silyl enol ether. The substrate for this initial cyclization reaction contained all of the carbons needed for completing the total synthesis. The electrolysis proceeded in high yield and could be accomplished with the use of a 6 V lantern battery.