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A novel procedure for the synthesis of enantiomeric (S)- and (R)-SRI 834 is described. The scheme involves the asymmetrization of prochiral tetrahydrofuran-2,2-dimethanol by the enantiopos-differentiating hydrolysis of dibutyrate. The formed enantioriched synthon was used as a common intermediate for the preparation of the enantiopure target compounds.

The enantiospecific synthesis of optically pure dodecyl-methylenecyclopropane acetic acid provides the material for a study of the toxicity of hypoglycine A. The process involves double nucleophilic displacement of the sulfate group in dodecyl-1, 2-cyclic sulfate with the lithium salt of beta-(trimethylsilyl)ethyl phenyl sulfone, followed by oxidation to form the acid in 65% yield. The cyclic sulfate is derived by epoxidation of trans-pentenol with chiral diethyl tartrate, followed by coupling with undecynyllithium.

Vinylformylation of 3-(3- 4-fluorophenyl -1- 1-methylethyl -1H-indole) using 3-(N-methyl-N-phenylamino)acrolein and POCl3 led to the formation of the alpha,beta-unsaturated aldehyde, 3-(3- 4-fluorophenyl -1- 1-methyletheyl -1H-indol-2-yl)-2(E)-propenal, in good yield. The reaction utilized a propeniminium salt easily derived from the reaction of oxalyl chloride in acetonitrile with N-methylformanilide and butyl vinyl ether. Moreover, the reaction can be used in converting aminoacrolein intermediates into substituted indoles via POCl3-activation.

A practical synthetic strategy is described for a chiral azabicyclooctanyl derivative, a potent DPP-4 inhibitor, starting from a commercially available nortropine. The stereogenic center of this derivative is established by using a modified protocol of Ellman's diasteroselective addition of a benzylic nucelophile to tert-butanesulfinimine.

A nonenzymatic method of synthesizin the enantiomerically pure phospholipids (R)- and (S)-tetrahydro-2-( octadecyloxy methyl)-2-furanmethanol is introduced. The procedure involves the enantiodifferentiating functionalization of prochiral tetrahydrofuran-2,2-dimethanol 'using l-menthone as the chiral template.' It generates chiral intermediates which are transformed into the final products via alkylation with octadecyl bromide and elimination of the chiral auxiliary with trifluoroacetic acid.