375826-91-8Relevant academic research and scientific papers
Total synthesis of the polyene macrolide dermostatin A
Sinz, Christopher J,Rychnovsky, Scott D
, p. 6561 - 6576 (2007/10/03)
Herein we provide full details of studies which culminated in the first total synthesis of the polyene macrolide dermostatin A, confirming our earlier stereochemical assignment. A highly convergent synthesis was developed, featuring the cyanohydrin acetonide method for polyol construction and a Stille approach to polyene introduction. The strategies and tactics developed en route should be of value for the preparation of other members of the polyene macrolide class, as well as analogs of the dermostatins.
The exceptional chelating ability of dimethylaluminum chloride and methylaluminum dichloride. The merged stereochemical impact of α- and β-stereocenters in chelate-controlled carbonyl addition reactions with enolsilane and hydride nucleophiles
Evans,Allison,Yang,Masse
, p. 10840 - 10852 (2007/10/03)
A systematic investigation of the stereoselectivity in Lewis acid-promoted (Mukaiyama) aldol reactions of achiral unsubstituted enolsilanes and chiral β-hydroxy aldehydes proceeding under conditions favoring chelation control is presented. Good stereocontrol can be realized for enolsilane aldol reactions of β-alkoxy and β-silyloxy aldehydes bearing only an α- or a β-stereogenic center. Examination of the chelated intermediates for α,β-disubstituted aldehydes concludes that the syn aldehyde diastereomer possesses the arrangement of stereocenters wherein the α- and β-substituents impart a reinforcing facial bias upon the aldehyde carbonyl. Aldol reactions of syn aldehydes were thus observed to proceed with uniformly excellent diastereofacial selectivity. Aldol reactions of the corresponding anti aldehydes containing opposing stereocontrol elements at the α- and β-positions exhibit variable and unpredictable selectivity.
