Total Synthesis of the Boron-Containing Ion Carrier Antibiotic Macrodiolide Tartrolon B
作者:Johann Mulzer、Markus Berger
DOI:10.1021/jo035391p
日期:2004.2.1
The first totalsynthesis of the boron-containing macrodiolide antibiotic tartrolonB is reported in full detail. Two convergent approaches to the target compound are described, the first of which eventually failed, due to sensitive functionality. In the second, successful route the key step was a stereoselective boron-mediated aldol addition of a bicyclic acetonide protected ketone to a diene-aldehyde
Stereoselective construction of quaternary chiral centers using Ti(III)-mediated opening of 2,3-epoxy alcohols: studies directed toward the synthesis of penifulvins
作者:Tushar Kanti Chakraborty、Amit Kumar Chattopadhyay、Rajarshi Samanta、Ravi Sankar Ampapathi
DOI:10.1016/j.tetlet.2010.06.076
日期:2010.8
A trisubstituted α,β-unsaturated ester moiety was suitably placed in a molecule also bearing an epoxy alcohol moiety at its other end to intramolecularly trap the intermediate radical, which was formed when the molecule was treated with Cp2Ti(III)Cl to regio- and stereoselectively open its epoxy ring, giving rise to a quaternary chiral center. The method was subsequently used in an attempt to construct
Total Synthesis of (+)-Calyculin A and (−)-Calyculin B: Asymmetric Synthesis of the C(9−25) Spiroketal Dipropionate Subunit
作者:Amos B. Smith、Gregory K. Friestad、Joseph Barbosa、Emmanuel Bertounesque、Kenneth G. Hull、Makoto Iwashima、Yuping Qiu、Brian A. Salvatore、P. Grant Spoors、James J.-W. Duan
DOI:10.1021/ja992134m
日期:1999.11.1
An asymmetricsynthesis of the stereochemically fully endowed C(9−25) spiroketal fragment (+)-BC of the calyculins (1−8) is described. Highlights of the synthesis include: a highly diastereoselective IBr-induced iodocarbonate cyclization to introduce the C(21) stereocenter in epoxide (+)-18, fragment unions exploiting the reaction of acyl anion equivalents with epoxides to construct masked advanced
Evolution of a Gram-Scale Synthesis of (+)-Discodermolide
作者:Amos B. Smith、Thomas J. Beauchamp、Matthew J. LaMarche、Michael D. Kaufman、Yuping Qiu、Hirokazu Arimoto、David R. Jones、Kaoru Kobayashi
DOI:10.1021/ja0015287
日期:2000.9.1
stereocontrolled total synthesis of the potent antimitotic agent (+)-discodermolide (1) has been achieved on gram scale. Key elements of the successful strategy include (1) elaboration of three advanced fragments from a common precursor (CP) which embodies the repeating stereochemical triad of the discodermolide backbone, (2) σ-bond installation of the Z trisubstituted olefin, exploiting a modifiedNegishi cross-coupling
作者:Amos B. Smith、Yuping Qiu、David R. Jones、Kaoru Kobayashi
DOI:10.1021/ja00153a030
日期:1995.12
formulae (2) and (13> and the enantiomeric and diastereoisomeric forms thereof are disclosed as are methods for their preparation and novel intermediates used in such methods. Their use in the totalsynthesis of a compound of formula (1> and enantiomeric and diastereoismeric forms thereof is disclosed. Also claimed are various intermediates prepared in synthesising (1) from (2) and (13).