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A diastereoselective mono-allylation reaction at the α-position of symmetric cyclic ketones by using tert-butanesulfinamide as a chiral auxiliary is explored. Excellent yields and high diastereomeric ratios were achieved under palladium(0) catalysis in the presence of a readily available achiral phosphine ligand.

A direct multi-component coupling of (2S,4R,5S)-N-tosyl-4-methyl-5-phenyl-1,2,3-oxathiozolidine-2-oxide with mesityl magnesium bromide, LHMDS and a range of aldehydes produces chiral sulfinimines in essentially optically pure form in an operationally simple single pot procedure.

A synthesis of the spirocyclic core structure of halichlorine, an inhibitor of the induced expression of VCAM-1 and the pinnaic acids, inhibitors of PLA 2 , is presented. A two-directional strategy is employed, in conjunction with a tandem oxime formation/Michael addition/cycloaddition to form the key azaspirocyclic skeleton in a very direct manner.

Synthesis of a range of chiral non-racemic vinyl aziridines with varying substitutions on the alkene has been achieved by the reaction of ( S S )- tert -butylphenylsulfinimine with a range of ylides derived by deprotonation of substituted allyltetrahydrothiophenium salts. Yields of the substituted vinyl aziridines range from 0% to 90%, with trans:cis ratios between 1:1 and 0:100 and diastereomeric excesses of up to 99%.

A 6-step synthesis of the potent anthelmintic SB-201561 is described. The key stage of the synthesis is a novel Beckmann type oxime fragmentation to give a lactone, followed by a 2-step reassembly of the spirolcetal moiety.

The formal synthesis of (±)-histrionicotoxin and (±)-histrionicotoxin 235A using a two-directional strategy has been accomplished. The key feature of the synthesis is a tandem oxime formation/Michael addition/nitrone cycloaddition sequence, which form the azaspiro[5.5]undecane skeleton in two operations from an acyclic symmetrical precursor.

A two-directional synthesis strategy and a tandem deprotection/double intramolecular Michael addition provides a very direct route to the 4,6-disubstituted quinolizidine 4.