A new short strategy to prepare the spiroketal fragment of calyculins is presented. A novel Seyferth–Gilbert type homologation of hindered lactols to the corresponding alkynes has been achieved for the first time. The spirocyclization was achieved efficiently via a DIHMA (double intramolecular hetero-Michael addition) process of this hindered ynone. The spirocyclization rate is not dependent on...

Four glycoglycerolipids with different head groups have been synthesized and their physicochemical properties studied. The lengths of the head groups from a mono-saccharide to a trisaccharide, in addition to the anomeric stereochemistry for the smaller glycoglycerolipids, have been modified. The synthesis has been optimized to avoid glycerol epimerization and to allow up-scaling. The physicoche...

The synthesis of (+/-)-1'-epi-stegobinone has been accomplished in ten steps and 17% overall yield from a recently reported silacyclopropane-derived diol. All stereocenters of the final product were established relative to the stereochemistry of the initial silacyclopropane. This synthesis represents the first time silacyclopropane reactivity has been employed in a target-directed synthesis.

The perfluoro- and perprotiopentaphenylboroles 1 and 2 react with dihydrogen to effect H-H bond cleavage and formation of boracyclopentene products. The mechanism of this reaction has been studied experimentally through evaluation of the kinetic properties of the slower reaction between 2 and H(2). The reaction is first-order in both [borole] and [H(2)] with activation parameters of ΔH(‡) = 34(...

The second-generation synthesis of 3'-hydroxypacidamycin D (2) has been accomplished via an Ugi-four component reaction at a late stage of the synthesis. This approach provided ready access to a range of analogues including diastereomers of the diaminobutylic acid residue and hybrid-type analogues of mureidomycins. Biological evaluations of these analogues indicated that the stereochemistry at ...

On the occasion of 70th birthday Franco Cozzi (Università degli Studi di Milano), a selection articles by his friends, colleagues, and former students, who are among leading researchers in field Organic Chemistry Italy, Europe, overseas, covering entire spectrum synthetic organic, bioorganic, physical-organic chemistry organic stereochemistry, is presented.