Rodney A. Fernandes

An asymmetric dihydroxylation route to enantiomerically pure norfluoxetine and fluoxetine

An efficient, practical asymmetric synthesis of (R)-norfluoxetine 1 and (R)-fluoxetine 2 has been achieved. The synthetic strategy features a Sharpless asymmetric dihydroxylation (SAD) route to the common building block 1,3-amino alcohol 9, from which (R)-norfluoxetine, (R)-fluoxetine and other related analogs can be synthesized.

An asymmetric dihydroxylation route to (S)-oxybutynin

An asymmetric synthesis of (S)-oxybutynin 1 is described using the Sharpless asymmetric dihydroxylation of α-cyclohexylstyrene as the key step.

ASYMMETRIC SYNTHESIS OF (S) - MASSOIALACTONE

Abstract An asymmetric synthesis of (S)-(+)-Massoialactone is described using the Sharpless asymmetric dihydroxylation and the regiospecific nucleophilic opening of a cyclic sulfate as key steps.

A Stereoselective Synthesis of Dihydrosphingosine

A highly enantioselective synthesis of D-(+)-erythro-dihydrosphingosine (sphinganine) as its triacetate derivative 10, starting from palmityl alcohol (3) and employing the Sharpless asymmetric dihydroxylation as the key step, is described.

Double stereodifferentiation in asymmetric dihydroxylation: application to the first diastereoselective synthesis of l-xylo-[2R,3S,4S]-C18-phytosphingosine

Abstract The first diastereoselective synthesis of l- xylo-(2R,3S,4S)-C18-phytosphingosine (1) has been achieved by double stereodifferentiation of enantiomerically enriched terminal olefin 14 using (DHQD)2–PHAL ligand in an asymmetric dihydroxylation with a diastereomeric ratio of 83:17. This phytosphingosine was fully characterized by the physical and spectral data of the corresponding tetraacetate 21.

A chiron approach to the total synthesis of (-)-juglomycin A, (+)-kalafungin, (+)-frenolicin B, and (+)-deoxyfrenolicin.

A general, efficient, and common strategy for the synthesis of (-)-juglomycin A, (+)-kalafungin, (+)-frenolicin B, and (+)-deoxyfrenolicin is reported here. The strategy involves the synthesis of a key building block alkyne from a cheap chiral pool material, D-glucono-δ-lactone, Dötz benzannulation, oxa-Pictet-Spengler reaction, and H(2)SO(4)-mediated epimerization.

Total synthesis of (+)-demethoxycardinalin 3.

The total synthesis of (+)-demethoxycardinalin 3 is described. The synthetic strategy features the synthesis of dimeric Fischer carbene and its use in a bidirectional Dötz benzannulation reaction to set the dimeric structure of the cardinalins. The oxa-Pictet-Spengler reaction was used to construct the pyran rings. The synthesis is completed in seven steps and an overall yield of 7%.

A short and efficient stereoselective synthesis of dihydrosphingosine triacetate

Abstract A highly enantiocontrolled synthesis of d -(+)- erythro -dihydrosphingosine (sphinganine) triacetate is described using the Sharpless asymmetric dihydroxylation and the regiospecific nucleophilic opening of a cyclic sulfite as key steps.

A protecting-group-free synthesis of Hagen's gland lactones.

A practical protecting group free synthesis of Hagens gland lactones 1 and 2 is accomplished in four steps and 25.6 and 37.4% overall yields, respectively. The strategy relies on a one-pot conversion of D-glucono-δ-lactone to β-hydroxy-γ-vinyl-γ-lactone, cross-metathesis, and iodocyclization-deiodinization as key steps.

Total Syntheses of All Stereoisomers of Phenatic Acid B

The total syntheses of all stereoisomers of phenatic acid B and determination of their absolute configuration are described. The synthetic strategy is based on an efficient combination of the Sharpless asymmetric dihydroxylation, the Johnson-Claisen rearrangement, and hydroboration-oxidation. It involves 11-12 steps and overall yield of 5-8%.