197771-01-0Relevant academic research and scientific papers
Synthetic studies on a marine natural product, palmerolide A: Synthesis of C1-C9 and C15-C21 fragments
Kaliappan, Krishna P.,Gowrisankar, Parthasarathy
, p. 1537 - 1540 (2008/02/05)
An efficient cross metathesis and Pd-catalyzed allylic rearrangement have been successfully used to construct the northern hemisphere of a cytotoxic marine natural product, palmerolide A. Georg Thieme Verlag Stuttgart.
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.
Studies on the total synthesis of the macrolide antitumor agent rhizoxin. 1. Synthesis of the C3-C13 segment
White, James D.,Nylund, Christine S.,Green, Neal J.
, p. 7329 - 7332 (2007/10/03)
An asymmetric synthesis of the C3-C13 segment of rhizoxin is described in which the relative stereochemistry of C7 and C8 is established through a chelation-controlled allylation followed by Mitsunobu inversion, and the pyran ring is constructed by a phot
Synthetic Studies on the Rhizoxins. 1. Two Stereoselective Routes to a Functionalized C1-C9 Subunit
Keck, Gary E.,Park, Min,Krishnamurthy, Dhileepkumar
, p. 3787 - 3788 (2007/10/02)
Two syntheses of a potential C1-C9 subunit of rhizoxin are described.In the first, chelation-controlled allylstannane addition to optically pure aldehyde 3, conversion to unsaturated ester 7, and stereoselective intramolecular Michael addition is used to
