A highly concise and convergent synthesis of HCV polymerase inhibitor Deleobuvir (BI 207127): application of a one-pot borylation-Suzuki coupling reaction.

A highly concise and convergent synthesis of HCV polymerase inhibitor Deleobuvir (BI 207127, 1) was achieved, featuring efficient Pd-catalyzed one-pot borylation-Suzuki coupling where TFP was identified as the unique ligand effective for these transformations.

Synthesis and configurational assignment of the amino alcohol in the eastern fragment of the GE2270 antibiotics by regio- and stereoselective addition of 2-metalated 4-bromothiazoles to alpha-chiral electrophiles.

A synthesis of the eastern fragment of the thiazole peptide GE2270 A (1) has been developed. The synthetic approach relies on the regioselective functionalization of 2,4-dibromothiazole (5) via metalation and nucleophilic addition (at C2) or palladium-mediated cross-coupling (at C2 or C4). The stereochemistry at the N-bearing stereocenter was established by coupling of 2-metalated 4-bromothiazoles (4) to enantiomerically pure mandelic acid derivatives.

Diastereoselective hydroformylation of 2-substituted allylic o-DPPB-esters-on the origin of 1,2-asymmetric induction.

2-Substituted secondary alcohol o-DPPB esters (o-DPPB=ortho-diphenylphosphanylbenzoyl) have been prepared and their o-DPPB-directed diastereoselective hydroformylation examined. It was found that the diastereoselectivity increased as a function of the steric demand of the substituents both at the stereogenic center and in the alkene 2-position. Hydrolytic cleavage of the o-DPPB group afforded-via the lactols 29-the corresponding lactones 30, the relative configurations of the vicinal stereogenic centers of which were ascertainable by 2D-NOESY spectroscopy.

Cyclotrimethylenetriphosphinic Acid.

The cyclotrimethylenetriphosphinic acid (1), isoelectronic to the cyclotriphosphoric acid, is formed in the hydrolysis of 1,1,3,3,5,5-hexakis(dimethylamino)-1λ ,3λ ,5λ -[1,3,5]triphosphinine. Compound 1 is stable to acids and bases. On heating for a longer period of time in D O each of the three methylene groups is monodeuterated.