106357-32-8Relevant articles and documents
The stereoselective synthesis of the C6-C18 fragment of scytophycin C employing a novel synthetic methodology
Yadav, Jhillu S.,Sunitha,Subba Reddy, Basi V.,Gyanchander
experimental part, p. 2933 - 2938 (2009/04/07)
A novel synthetic approach towards the stereoselective synthesis of the C6-C18 fragment of the biologically active antitumor agent scytophycin C is described. The synthesis involves Marouka allylation, base-catalyzed intramolecular conjugate addition, Wit
Total synthesis of rhizoxin D, a potent antimitotic agent from the fungus Rhizopus chinensis
White, James D.,Blakemore, Paul R.,Green, Neal J.,Hauser, E. Bryan,Holoboski, Mark A.,Keown, Linda E.,Nylund Kolz, Christine S.,Phillips, Barton W.
, p. 7750 - 7760 (2007/10/03)
Rhizoxin D (2) was synthesized from four subunits, A, B, C, and D representing C3-C9, C10-C13, C14-C19, and C20-C27, respectively. Subunit A was prepared by cyclization of iodo acetal 21, which set the configuration at C5 of 2 through a stereoselective addition of the radical derived from dehalogenation of 21 at the β carbon of the (Z)-α,β-unsaturated ester. Aldehyde 29 was obtained from phenylthioacetal 24 and condensed with phosphorane 30, representing subunit B, in a Wittig reaction that gave the (E,E)-dienoate 31. This ester was converted to aldehyde 33 in preparation for coupling with subunit C. The latter in the form of methyl ketone 55 was obtained in six steps from propargyl alcohol. An aldol reaction of 33 with the enolate of 55 prepared with (+)-DIPCl gave the desired β-hydroxy ketone 56 bearing a (13S)-configuration in a 17-20:1 ratio with its (13R)-diastereomer. After reduction to anti diol 57 and selective protection as TIPS ether 58, the C15 hydroxyl was esterified to give phosphonate 59. An intramolecular Wadsworth-Emmons reaction of aldehyde 62, derived from δ-lactone 60, furnished macrolactone 63, which was coupled in a Stille reaction with stannane 68 to give 2 after cleavage of the TIPS ether.
Synthesis of the C1-C13 fragment of leucascandrolide A.
Crimmins,Carroll,King
, p. 597 - 599 (2007/10/03)
[reaction: see text] The synthesis of the C1-C13 fragment 3 of leucascandrolide A has been completed utilizing a stereoselective and regioselective reductive cleavage of a highly functionalized spiroketal to incorporate the cis-2,6-disubstituted tetrahydropyan. The spiroketal was constructed by addition of a lithiated pyrone 5 to aldehyde 6.
