159292-67-8Relevant academic research and scientific papers
TOTAL SYNTHESIS OF TRIOXACARCIN DC-45-A2 AND PREPARATION OF TRIOXACARCIN ANALOGS
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, (2016/07/05)
In one aspect, the present invention provides novel derivatives of trioxacarin analogs of the formula (I) wherein the variables are as defined herein. The application also provides compositions, methods of treatment, and methods of synthesis thereof.
Total synthesis of trioxacarcin DC-45-A2
Nicolaou, K. C.,Cai, Quan,Qin, Bo,Petersen, Mette T.,Mikkelsen, Remi J. T.,Heretsch, Philipp
, p. 3074 - 3078 (2015/07/01)
An enantioselective total synthesis of trioxacarcin DC-45-A2 (1) featuring a novel Lewis acid-induced cascade rearrangement of epoxyketone 6 to forge the polyoxygenated 2,7-dioxabicyclo[2.2.1]heptane core of the molecule is described.
Chiral lithium amide base-mediated rearrangement of bis-protected meso-4,5-dihydroxy cyclohexene oxides: Enantioselective synthesis of (4R,5S) and (4S,5R)-4,5-bis(tert-butyldimethylsilyloxy)cyclohex-2-enone
O'Brien, Peter,Poumellec, Pierre
, p. 2435 - 2441 (2007/10/03)
The asymmetric synthesis of (4R,5S)- and (4S,5R)-4,5-bis(tert-butyldimethylsilyloxy)cyclohex-2-enone are described. Such bis-protected enones are useful intermediates in synthesis, and compounds with (4S,5R)-stereochemistry have previously been prepared from D-(-)-quinic acid. This paper reports the first synthesis of enones with (4R,5S)-stereochemistry. The route to the bis-protected enones involves chiral base-mediated rearrangement of meso-cyclohexene oxides to allylic alcohols followed by PDC oxidation. Two new chiral base reactions are described: rearrangement of a trans-epoxide generates an allylic alcohol of 76% ee (93% yield) whilst that of a cis-epoxide produces an allylic alcohol of 92% ee (38% yield); suggestions for the observed differences in yield and enantioselectivities are proposed.
Chiral base-mediated rearrangement of meso-cyclohexene oxides to allylic alcohols
O'Brien, Peter,Poumellec, Pierre
, p. 8057 - 8058 (2007/10/03)
Highly enantiomerically enriched allylic alcohols have been generated by rearranging single diastereomers of meso-cyclohexene oxides using a homochiral lithium amide base. PDC oxidation of each allylic alcohol product affords a different enantiomer of a synthetically useful cyclohexenone.
Simple Designs for the Construction of Complex Trans-Fused Polyether Toxin Frameworks. A Linear Strategy Based on Entropically Favored Oxirane Ring Enlargement in Epoxycycloalkenes Followed by Carbon-Carbon or Carbon-Oxygen Bond-Forming Cyclizations
Alvarez, Eleuterio,Diaz, Maria T.,Perez, Ricardo,Ravelo, Jose L.,Regueiro, Alicia,et al.
, p. 2848 - 2876 (2007/10/02)
A successful design for the construction of trans-fused medium-size cyclic ethers is described.The key features of the synthesis are as follows: (i) intramolecular oxirane ring expansion in cycloalkenes to give bridged oxabicyclic systems and (ii) linear, one- or two-directional synthetic operations which generate external oxocycles in single reaction steps.The general approach involves the intramolecular addition of a stable γ-alkoxy-substituted allylstannane to an aldehyde carbonyl group, and the entire reaction is conducted in a one-pot process which includes the following: (i) vic-diol fragmentation from the bridged oxabicyclic precursor and (ii) Lewis acid-induced cyclization of the resulting aldehyde-allylic tin system.While the present strategy was mostly developed around racemic models, the potential for adoption of enantioselective features is immediate.The versatility, scope, limitations, and potential applications of the present technology are discussed in detail.
