112837-17-9Relevant articles and documents
Total synthesis of branimycin: An evolutionary approach
Enev, Valentin S.,Felzmann, Wolfgang,Gromov, Alexey,Marchart, Stefan,Mulzer, Johann
, p. 9651 - 9668 (2012/09/21)
The first total synthesis of the macrolactone antibiotic branimycin (4) has been described. The key disconnection leads to a cis-dehydrodecalone core and a polyketide side chain which are connected via organometallic addition. The dehydrodecalone core was targeted via altogether five different approaches featuring various kinds of chiral elements and ring-closing methodology. In the end the most successful method starting from diepoxynaphthalene 109 was chosen to carry on with the synthesis. Thus the oxygen functions and carbon appendages were introduced via organometallic desymmetrization reactions to generate epoxy ketone 107, to which vinyl iodide 11 was added after conversion into the organolithium species. The synthesis was completed by introducing the ester side chain via Michael addition and subsequent macrolactonization. Competitive approach: The first total synthesis of the macrolactone antibiotic branimycin is described (see figure). The dehydrodecalin core was targeted via five competing approaches featuring various kinds of chiral elements and ring-closing methodology. In this "Darwinian" struggle the most successful route emerged and led to the completion of the synthesis. Copyright
Convenient new syntheses of R-(+)-5-benzyloxymethyl-5H-furan-2-one- a building block en route to L-nucleosides
Fazio, Fabio,Maliakal, Davis,Schneider, Manfred P.
, p. 1323 - 1328 (2007/10/03)
R-(+)-5-Benzyloxymethyl-5H-furan-2-one (R-(1)) was obtained from commercially available R-(-)-2-benzyloxymethyl oxirane (R-(2)) in two and three steps, respectively. Key steps are a) the nucleophilic ring opening of the oxirane moiety with dianions derived from either PhSeCH2CO2H or PhSCH2CO2H; b) oxidation to the corresponding 1-oxides and c) concomitant or thermally induced syn-elimination. R-(1) was obtained with ≥97% ee and ≥95% ee, respectively.
Synthesis of Optically Active Butenolides and γ-Lactones by the Sharpless Asymmetric Dihydroxylation of β,γ-Unsaturated Carboxylic Esters
Harcken, Christian,Brueckner, Reinhard
, p. 2750 - 2752 (2007/10/03)
Keywords: asymmetric synthesis; butenolides; dihydroxylations; furanones; lactones