77152-88-6Relevant articles and documents
Asymmetric total synthesis of sperabillins B and D via lithium amide conjugate addition
Davies, Stephen G.,Haggitt, Jane R.,Ichihara, Osamu,Kelly, Richard J.,Leech, Michael A.,Mortimer, Anne J. Price,Roberts, Paul M.,Smith, Andrew D.
, p. 2630 - 2649 (2007/10/03)
Diastereoselective conjugate addition of homochiral lithium (R)-N-allyl-N-α-methylbenzylamide to methyl (2E,5E)-hepatadienoate, followed by protecting group manipulation and subsequent iodocyclocarbamation allows a concise route to the core fragment, methyl (3R,5R,6R)-3,6-diamino-5- hydroxyheptanoate, of sperabillins B and D. Differentiation between the C-3 and C-6 primary amino groups of this core amino acid was readily achieved by treatment with acetone, giving the 5,6-isopropylidene and C-3-imine protected diamine, with subsequent regioselective acylation of the C-6-nitrogen facilitating the total synthesis of sperabillin D in 10.8% overall yield, and the first asymmetric synthesis of sperabillin B in 5.8% overall yield.