17092-07-8Relevant academic research and scientific papers
Total synthesis with a chirogenic opening move demonstrated on steroids with estrane or 18a-homoestrane skeleton
Quinkert,Del Grosso,Doring,Doring,Schenkel,Bauch,Dambacher,Bats,Zimmermann,Durner
, p. 1345 - 1391 (2007/10/02)
A concept of first choice for the synthesis of the title compounds had been proposed by Dane in the late 1930s. It was soon turned down, because the opening move - a chirogenic Diels-Alder reaction - did not work. With Lewis acids as mediators, however, a successful start has been achieved now. With Ti complexes of chelating ligands (Seebach's TADDOLs (= α,α,α',α'-tetraaryl-1,3-dioxolane-4,5-dimethanols)), enantioselective formation of the desired adducts does occur. Efficient total syntheses of 2 and 3a have been accomplished.
N,S-DIMETHYL-S-PHENYLSULFOXIMINE. A REAGENT FOR THE OPTICAL RESOLUTION OF KETONES
Johnson, Carl R.,Zeller, James R.
, p. 1225 - 1234 (2007/10/02)
The addition of the α-lithio derivative of (+)- or (-)-N,S-dimethyl-S-phenylsulfoximine to selected dl-ketones was carried out at -78 deg C in tetrahydrofuran followed by acid quench at that temperature to produce mixtures of diastereomeric β-hydroxysulfoximines.The optically-active diastereomers were chromatographically separated on silica gel.The purified diastereomers were thermolyzed at ca. 130 deg to produce optically-active ketones and the optically-active sulfoximine which could be recycled.
Synthesis of A-ring aromatic steroids
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, (2008/06/13)
Total synthesis of steroids of the estrone and equilenin series involving conjugate 1,4-addition of a meta-substituted benzyl organometallic reagent to a C/D bicyclic methylene ketone. An aromatization of the B-ring of Δ 9(11) estrone derivatives.
