184435-75-4Relevant articles and documents
Stereoselective total synthesis of (+)-giganin and its C10 epimer by using late-stage lithiation-borylation methodology
Fletcher, Catherine J.,Wheelhouse, Katherine M. P.,Aggarwal, Varinder K.
, p. 2503 - 2506 (2013/04/10)
The first total synthesis of (+)-giganin and its unnatural diastereoisomer (+)-C10-epi-giganin has been completed in a total of 13 linear steps, and 7 % and 8 % overall yield, respectively (see scheme; (-)-sp= (-)-sparteine, (+)-sps=(+)-sparteine surrogate). Lithiation-borylation methodology has been successfully applied in the key step, to couple together advanced intermediates with very high diastereoselectivity, thus demonstrating its power as a tool for total synthesis. Copyright
Concise syntheses of the natural products (+)-sylvaticin and (+)-cis-sylvaticin
Donohoe, Timothy J.,Harris, Robert M.,Williams, Oliver,Hargaden, Grainne C.,Burrows, Jeremy,Parker, Jeremy
supporting information; experimental part, p. 12854 - 12861 (2010/01/29)
Two concise syntheses of the natural products cis-sylvaticin and sylvaticin are reported, using oxidative cyclization methodology as the key step. A sequential solvolysis/hydride shift/intramolecular reduction cascade was used to establish the trans stereochemistry of one of the THF rings of sylvaticin.
Convergent total synthesis of squamostolide
Quinn, Kevin J.,Smith, Austin G.,Cammarano, Carolyn M.
, p. 4881 - 4886 (2008/02/01)
A convergent total synthesis of the Annonaceous acetogenin squamostolide, in a longest linear sequence of nine steps from d-mannitol, is reported. Central to the efficiency of the synthesis is a highly selective tandem ring-closing/cross metathesis step in which lactone formation and fragment coupling are accomplished.
A modular synthesis of annonaceous acetogenins
Marshall, James A.,Piettre, Arnaud,Paige, Mikell A.,Valeriote, Frederick
, p. 1771 - 1779 (2007/10/03)
A synthesis of four Annonaceous acetogenins, asiminocin, asimicin, asimin, and bullanin, by a modular approach from seven fundamental subunits, A-G, is described. The approach employs a central core aldehyde segment, C, to which are appended an aliphatic terminus, A or B, a spacer subunit, D or E, and a butenolide terminus, F or G. Coupling of the A, B, D, and E segments to the core aldehyde unit is effected by highly diastereoselective additions of enantiopure allylic indium or tin reagents. The butenolide termini are attached to the ACD, BCE, or BCD intermediates by means of a Sonogashira coupling. The design of the core, spacer, and termini subunits is such that any of the C30, C10, or C4 natural acetogenins or stereoisomers thereof could be prepared. IC50 values for the four aforementioned acetogenins against H-116 human colon cancer cells were found to be in the 10-3 to 10-4 μM range. The IC90 activities were ca. 10-3 μM for asimicin and asimin but only 0.1-1 μM for bullanin and asiminocin.
Preparation of (+)-Hamabiwalactone B via Stille coupling of an enantiomerically pure stannylfuranone
Richec?ur, Alexandre M. E.,Sweeney
, p. 389 - 395 (2007/10/03)
An unambiguous and highly enantioselective total synthesis of the naturally occurring 2(5H)-furanone Hamabiwalactone B has been achieved. The key step was a palladium-catalysed cross coupling ('Stille' coupling) of the previously unreported stannylfuranone 2 with (E)-iodoalkene 3. The enantiomeric purity of the synthetic natural product was ≥99%, as judged by chiral HPLC. (C) 2000 Elsevier Science Ltd.
Degradation and Absolute Configurational Assignment to C34-Botryococcene
White, James D.,Somers, Todd C.,Reddy, G. Nagabushana
, p. 4991 - 4998 (2007/10/02)
C34-Botryococcene, the major hydrocarbon constituent of the B race of Botryococcus braunii, was degraded by ozonolysis of its dihydro derivative followed by Baeyer-Villiger oxidation to γ-valerolactone, 2,5-dimethylhexanolactone, and 2-ethyl-2,
SYNTHESIS OF OPTICALLY ACTIVE PROSTAGLANDIN ANALOGUE (8R,11S,12R,15S)-10-OXA-11-METHYL-11-DEOXY-PGE2
Nokami, Junzo,Ono, Toshio,Kajitani, Yasunobu,Wakabayashi, Shoji
, p. 707 - 708 (2007/10/02)
The title compound has been synthesized via "three-component coupling process" which consisted of 1,4-addition of sulfonylcarbanion to a butenolide and alkylation of the resulting enolate with propargylic iodide.
