np8b00319_si_001.cif (20.5 kB)
Confirmation of the Revised Structure of Samoquasine A and a Proposed Structural Revision of Cherimoline
dataset
posted on 2018-07-18, 18:22 authored by Francis Dhoro, Jesse Parkin-Gibbs, Matthew McIldowie, Brian W. Skelton, Matthew J. PiggottThe identity of the natural product
samoquasine A has remained
obscure since its isolation from custard apple seeds in 2000. One
of the proposed structures, benzo[f]phthalazin-4(3H)-one, was prepared in two steps by regioselective ortho-lithiation/formylation of N,N-diisopropyl-2-naphthylamide, followed by cyclization
with hydrazine, but was shown to be different from the natural product.
Perlolidine, another candidate structure, was synthesized by a novel
route involving a β-selective Heck reaction of butyl vinyl ether.
Both perlolidine and samoquasine A are converted by trimethylsilyldiazomethane
into the same N-methyl derivative. In addition, the 13C NMR spectra of perlolidine and another structurally mis-assigned
natural product, cherimoline, are almost identical. Thus, both samoquasine
A and cherimoline are actually perlolidine.