The first stereoselective synthesis of (+)-nuciferol and (+)-nuciferal

Enantioselective synthesis of (+)-nuciferal, (+)-(E)-nuciferol and (+)-α-curcumene by chiral hydrogenesterification reaction

Using chiral hydrogenesterification reaction as the key step, the stereoselective synthesis of (+)-nuciferal 1, (+)-(E)-nuciferol 2 and (+)-a-curcumene 3 has been achieved.

Application of Meldrum's Acid in Natural Product Synthesis. Synthesis of Ar-Turmerone and α-Curcumene

Meldrum's acid (1) is employed in the synthesis of ar-turmerone (6) and α-curcumene (12). 1-( p-Tolyl)ethyl Meldrum's acid (3), synthesised by three different routes, was the key intermediate in these syntheses.

Convergent synthesis of trisubstituted Z-allylic esters by Wittig-Schlosser reaction

β-Lithiooxyphosphonium ylides, generated in situ from aldehydes and Wittig reagents, react readily with halomethyl esters to form trisubstituted Z-allylic esters. The methodology was applied to a total synthesis of the geranylgeraniol-derived diterpene (6S,7R,Z)-7-hydroxy-2-((E)-6-hydroxy-4-methylhex-4-enylidene)-6,10-dimethylundec-9-enyl acetate (12).

Stereospecific Pd(0)-Catalyzed Arylation of an Allylic Hydroxy Phosphonate Derivative: Formal Synthesis of (S)-(+)-ar-Turmerone

Reaction of the (1S)-allylic hydroxy phosphonate 1(S) with methyl chloroformate in pyridine yields the corresponding carbonate 3(S). The carbonate 3(S) undergoes a palladium-catalyzed arylation with p-tolyl tributylstannane to give both the 1E and 1Z vinyl phosphonates 6 (85:15). The E and Z vinyl phosphonates 6 were shown to have the opposite configuration at C-3. The major vinyl phosphonate isomer (3S,1E), was converted to (3S)-3-(p-tolyl)-butanal 8(S), completing a formal total synthesis of (S)-ar-turmerone 5a.

A diastereocontrolled synthesis of (+)-febrifugine: a potent antimalarial piperidine alkaloid

A diastereocontrolled synthesis of (+)-febrifugine, a potent antimalarial piperidine alkaloid, has been achieved using a chiral block having a bicyclo[3.2.1]octane framework which exhibits inherent convex-face selectivity.