threo- and erythro- β-Hydroxy-DL-aspartic acids

The preferred conformation of erythro- and threo-1,2-difluorocyclododecanes

Cyclododecane adopts a square-like structure with corner and edge CH(2) groups. In this study erythro- and threo-1,2-difluorocyclododecanes were prepared to explore whether the two vicinal C-F bonds, with different relative configurations, preferably locate at corner/edge or edge/edge locations. Conformational analysis comparing the diastereoisomers was explored by using a combination of (19)F{...

THE SYNTHESIS OF D-ERYTHRO- AND D-THREO-a-AMINO-

In 1931 Klenk and Diebold (1) reported that sphingosine, upon oxidative degradation, gave rise to myristic acid and an optically active dihydroxyaminobutyric acid, [o(]A3 = 33.4”, which these authors characterized as an cY-amino-p ,r-dihydroxy-n-butyric acid. 5 years later Fischer and Feldmann (2), starting from D-glyceric aldehyde, synthesized an optically active oc-amino-p ,r-dihydroxy-n-buty...

Antiproliferative Activity of β-Hydroxy-β-Arylalkanoic Acids

Article describes the synthesis of fifteen β-hydroxy-β-arylalkanoic acids by Reformatsky reaction using the 1-ethoxyethyl-2-bromoalkanoates, aromatic or cycloalkyl ketones or aromatic aldehydes. The short survey of previously reported synthetic procedures for title compounds, is given. The majority of obtained compounds exert antiproliferative activity in vitro toward human: HeLa, Fem-X cells, ...

Total synthesis of stereospecific sphingosine and ceramide.

A small-scale synthesis of the four sphingosine stereoisomers (d-erythro, l-erythro, d-threo, and l-threo) and lignoceroyl d- and l-erythro-sphingosines, which is suitable for synthesis of tritium-labeled compounds, is described. Ethyl dl-erythro-2-acetamino-3-hydroxy-4t-octadecenoate was esterified with l(+)-acetylmandeloyl chloride and the two diastereomers obtained were separated from each o...

Stereoselective Disposition of Bupropion and Its Three Major Metabolites: 4-hydroxybupropion, Erythro-dihydrobupropion, and Threo- Dihydrobupropion