Synthesis of the C(21)-C(26) fragment of superstolide A: concerning the stereochemistry of (E)-crotylboration reactions of alaninal derivatives.
A stereoselective synthesis of the C(21)-C(26) fragment of superstolide A has been completed. The absolute and relative stereochemistry of intermediate 14 has been conclusively proven by NMR and X-ray diffraction methods. In the course of this work, it was found that the stereochemistry of 3 had been misassigned in our previously reported synthesis of the C(18)-C(26) segment. This error stems from the unexpected diastereoselectivity in the double asymmetric reaction of N-acetyl-d-alaninal 1 and the tartrate ester modified (E)-crotylboronate (R,R)-2.
Department of Chemistry, University of Michigan, Ann Arbor 48109, USA.
Neal A
NA
Yakelis
William R
WR
Roush
D000409:Alanine / Q000031:analogs & derivatives* / Q000737:chemistry*; D002384:Catalysis; D007202:Indicators and Reagents; D018942:Macrolides / Q000138:chemical synthesis*; D015394:Molecular Structure; D013237:Stereoisomerism; D013764:Tetrahydronaphthalenes / Q000138:chemical synthesis*; D014961:X-Ray Diffraction
D007202:Indicators and Reagents; D018942:Macrolides; D013764:Tetrahydronaphthalenes; C091984:superstolide A; D000409:Alanine