An efficient de novo synthesis of uronic acid building blocks is described. The synthetic strategy relies on the stereoselective elongation of thioacetal protected dialdehydes 12 a and 17. The dialdehydes are prepared from D-xylose, a cheap and commercially available source. A highly stereoselective MgBr(2)OEt(2)-mediated Mukaiyama aldol addition to C4-aldehyde 12 a is performed to obtain D-glucuronic acid building block 16, whereas L-iduronic acid building block 22 is prepared by MgBr(2)OEt(2)-mediated cyanation of C5-aldehyde 17. Synthesis of a heparin disaccharide demonstrates the utility of the de novo strategy for the assembly of glycosaminoglycan oligosaccharides.

Two antiglaucoma drugs, bimatoprost and latanoprost, which are analogues of the prostaglandin, PGF2α, have been synthesized in just 7 and 8 steps, respectively. The syntheses employ an organocatalytic aldol reaction that converts succinaldehyde into a key bicyclic enal intermediate, which is primed for attachment of the required lower and upper side chains. By utilizing the crystalline lactone, the drug molecules were prepared in >99% ee.

The controversy over the absolute configuration of (+)-erythro-mefloquine, the less psychosis-causing enantiomer of the anti-malarial drug Lariam, has been resolved by Mosher ester crystallization. The configuration determined previously by physical methods is correct, whereas the configuration determined by three enantioselective syntheses is wrong.

C-Glycosides are carbohydrates that bear aC ÀC bond to an aglycon at the anomeric center.D ue to their high stability towardsc hemical and enzymatic hydrolysis,t hese compounds are widely used as carbohydrate mimics in drug development. Herein, we report ag eneral and exclusively bselective method for the synthesis of anaturally abundant acyl-C-glycosidic structural motif first found in the scleropentaside natural product family.ACorey-Seebachu mpolung reaction as the key step in the synthesis of scleropentaside Aa nd analogues enables the b-selective construction of the anomeric C À Cb ond starting from unprotected carbohydrates in only four steps.T he one-pot approach is highly atom-efficient and avoids the use of toxic heavy metals.

Re‐investigation of the l‐proline catalyzed double aldol cascade dimerization of succinaldehyde for the synthesis of a key bicyclic enal intermediate, pertinent in the field of stereoselective prostaglandin synthesis, is reported. The yield of this process has been more than doubled, from 14 % to a 29 % isolated yield on a multi‐gram scale (32 % NMR yield), through conducting a detailed study of the reaction solvent, temperature, and concentration, as well as a catalyst screen. The synthetic utility of this enal intermediate has been further demonstrated through the total synthesis of Δ12‐prostaglandin J3, a compound with known anti‐leukemic properties.