110171-23-8Relevant articles and documents
Oxysterols: 27-hydroxycholesterol and its radiolabeled analog
D'Ambra, Thomas E.,Javitt, Norman B.,Lacy, James,Srinivasan, Puliyur,Warchol, Tadeusz
, p. 401 - 407 (2007/10/03)
We describe a convenient and stereoselective route to the synthesis of 27-hydroxycholesterol. Also its radiolabeled analog, 22, 23 di [3H]-27-hydroxycholesterol with high specific radioactivity (55 Ci/mmol) was synthesized by this method. Julia
Total synthesis of (-)-ircinianin and (+)-wistarin
Uenishi, Jun'ichi,Kawahama, Reiko,Yonemitsu, Osamu
, p. 1691 - 1701 (2007/10/03)
(-)-Ircinianin (1), a cyclic furanosesterterpenetetronic acid isolated from a marine sponge (genus Ircinia), is synthesized in 17 steps from (S)-2-methylpropane-1,3-diol mono THP ether 10 and 3-furfural. The key step involves a NiCl2-CrCl2-mediated coupling reaction of iodotriene 9 with chiral aldehyde 8 in DMSO and subsequent intramolecular Diels-Alder reaction in one pot. Both reactions proceed very smoothly at room temperature and eventually give the cyclic product 30A possessing the desired cyclic skeleton of 1 in 60% yield. The structure of 30A is determined by X-ray crystallographic analysis. The stereochemistry of Diels-Alder reactions of 7A and another acyclic precursor 7B are discussed. The first total synthesis of (+)-wistarin (2) is accomplished in 55% yield by iodoether ring formation of 1 and hydrogenolysis of the iodide 33A. Based on the coupling constant in the proton NMR spectrum of 33A, the reported structure 2A is revised to 2B.
On the Mechanism of Lewis Acid Promoted Ene Cyclizations of ω-Unsaturated Aldehydes
Marshall, James A.,Andersen, Marc W.
, p. 5851 - 5856 (2007/10/02)
The diastereomerically labeled d1 enals 1 and 2 were prepared from (S)-3-bromo-2-methylpropanol 5 by a sequence involving homologation to the allylic alcohol 13 and Sharpless epoxidation to either the α- or the β-epoxide diastereomers 14 or 15.Reduction w