作者:Guncheol Kim、Margaret Y. Chu-Moyer、Samuel J. Danishefsky、Gayle K. Schulte
DOI:10.1021/ja00054a005
日期:1993.1
The first totalsynthesis of racemic indolizomycin (1) has been achieved. Initial investigations provided the functionalizcd indolizidine, 31, via (i) stereospecific intramolecular vinylsilane/carbinol amide cyclization (15→16), (ii) rhodium(II) acetate mediated diazoacetate insertion into thioamide 17, and (iii) epoxide introduction (25→27→29). Although subsequent attempts to fully elaborate 31 into
Treatment of 3-(9-methylundeca-7,9-dienyl)-9-methylene-2,8-dioxabicyclo[4.3.0]nonane-5,7-dione (3) with SnCl4 in CH2Cl2 at -80-degrees-C produced intramolecular [2+2] cycloadducts (6a-d) rather than intramolecular Diels-Alder adducts.
Collective total syntheses of cytochalasans and merocytochalasans
Stereoselective preparation of vinyl sulfones by protodesilylation of allyl silanes
作者:Raymond L. Funk、Joy Umstead-Daggett、Kay M. Brummond
DOI:10.1016/s0040-4039(00)60467-7
日期:1993.4
Allyl sulfones can be conjugated to furnish vinyl sulfones via allyl silane intermediates. The stereoselectivity observed in the protodesilylation step provides a new method for stereoselective preparation of (E)-di-and trisubstituted vinyl sulfones.