Enantioselective Syntheses of Ring-C Precursors of Vitamin B12. Substrate Control. A Novel Si-Assisted Elimination of Vinyl Bromides
摘要:
[GRAPHICS]Homochiral ring-C precursors 34 of Vitamin B-12 have been prepared by Ireland-Claisen rearrangement of allyl esters 32, followed by a novel Si-assisted elimination of HBr.
This invention relates to novel prostacyclin derivatives, their acceptable acid addition salts, solvates, hydrates and polymorphs thereof. The invention also provides compositions comprising a compound of this invention and the use of such compositions in methods of treating diseases and conditions beneficially treated by prostacyclin, and in particular those diseases and conditions beneficially treated by dilators of systemic and pulmonary arterial vascular beds or by platelet aggregation inhibitors.
Enantioselective Syntheses of Ring-C Precursors of Vit. B<sub>12</sub>. Reagent Control
作者:Peter A. Jacobi、Yongkai Li
DOI:10.1021/ol0275116
日期:2003.3.1
[GRAPHICS]Enelactones of the general structure S-(-)-I were prepared in three steps from alcohol 21 and acids 22 (ee approximate to 85%). Lactones S-(-)-I are versatile precursors to enelactams II of the type found in Vitamin B-12.
Enantioselective Syntheses of Ring-C Precursors of Vitamin B<sub>12</sub>. Substrate Control. A Novel Si-Assisted Elimination of Vinyl Bromides
作者:Peter A. Jacobi、Carlos Tassa
DOI:10.1021/ol036061u
日期:2003.12.1
[GRAPHICS]Homochiral ring-C precursors 34 of Vitamin B-12 have been prepared by Ireland-Claisen rearrangement of allyl esters 32, followed by a novel Si-assisted elimination of HBr.