Catalytic amounts of 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) are used in combination with [bis(acetoxy)iodo]benzene (BAIB) as a stoichiometric oxidant in the conversion of primary and secondary alcohols to carbonyl compounds. This procedure works efficiently at room temperature in almost all common solvents and neat in some cases. This process exhibits a very high degree of selectivity for the oxidation of primary alcohols to aldehydes, without any noticeable overoxidation to carboxyl compounds, and a high chemoselectivity in the presence of either secondary alcohols or of other oxidizable moieties. This procedure allows an easy, convenient, high-yielding method for the oxidation of alcohols starting from commercially available compounds.

The structure and absolute configuration of the marine antithrombotic product dysinosin A was confirmed by total synthesis. The strategy involved disconnections to three subunits, of which two were synthesized from the readily available l-glutamic acid, d-leucine, and d-mannitol. The Grubbs olefin metathesis carbocyclization reaction was utilized to prepare two intermediates.

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We describe the synthesis, chromatographic purification, and isolation of the epothiloneÀfolic acid conjugate BMS-753493, an investigational new drug candidate for the treatment of cancer. The main challenges for process development were the instability of BMS-753493 in aqueous solution, the design and optimization of the preparative chromatography, and the removal of phosphate salts and water from the purified material. The operating conditions of the batch chromatographic purification were optimized using a column adsorption model. The free-salt active pharmaceutical ingredient was isolated via the precipitation of its zwitterion following a careful determination of the isolation parameters that controlled thermal and pH-related decomposition. This process enabled the manufacturing of several batches (10À30 g) of cGMP quality BMS-753493.