81470-85-1Relevant academic research and scientific papers
Synthesis of Stereopentad Subunits of Zincophorin and Rifamycin-S through Use of Chiral Allenyltin Reagents
Marshall, James A.,Palovich, Michael R.
, p. 3701 - 3705 (2007/10/03)
The anti,anti adduct 3, from addition of the allenic stannane (P)-2 to the a-methyl-β-OBn aldehyde (S)-1 promoted by SnCl4, was converted to the stereopentad 6 by a sequence involving reduction to the (E)-allylic alcohol with Red-Al, Sharpless asymmetric epoxidation, and addition of the higherorder methyl cyanocuprate to the derived epoxide 5. Stereopentad 6 was converted to the acetonide acetal 15, an intermediate in Danishefsky's synthesis of zincophorin. By a similar sequence, adduct ent-4 was converted, via diol 19, to stereopentad 22, an intermediate in Kishi's synthesis of rifamycin-S. An alternative route to diol 19 was achieved from the MOM-protected derivative 28 of epoxy diol 18.
3-METHYL-γ-BUTYROLACTONE AS A SOURCE OF 2-METHYL-3-HYDROXYKETONES AND 2-METHYL-1,3-DIOLS: A SYNTHESIS OF THE C19-C27 FRAGMENT OF RIFAMYCIN S BY LINEAR ITERATION
Ziegler, Frederick E.,Kneisley, Alyssa
, p. 1725 - 1728 (2007/10/02)
3-Methyl-γ-butyrolactone has been employed as a source of 2-methyl-3-hydroxyketones after functioning as a template for the preparation of enantiomerically pure propionate chains.This method is exemplified by the preparation of the C19-C27 propionate frag
