Beilstein J. Org. Chem.2020,16, 135–139, doi:10.3762/bjoc.16.15
produce the target dihydropyridinones efficiently and in high yields.
Keywords: amidoallylation; aza-goniothalamin; dihydropyridinones; protecting-group-free; ring-closing metathesis; two-pot procedure; Introduction
Six-membered nitrogen heterocycles are prevalent in many naturally occurring and
right [7][8][9][10][11][12][13].
The relevance of dihydropyridones as lead compounds is exemplified by the detailed investigations into the synthesis and biological evaluation of aza-goniothalamin 1 and its analogues (Figure 1). (R)-(+)-Goniothalamin 2, a natural product isolated in 1967, was shown to
be cytotoxic against human leukaemia, kidney, ovarian and prostate cancer cell lines (IC50 = 25 µM, U251 cell line) [14][15][16]. In an attempt to increase the bioavailability of (R)-(+)-goniothalamin 2, aza-goniothalamin 1 was designed and synthesised; however, aza-goniothalamin 1 was found to have