628328-75-6Relevant academic research and scientific papers
Syntheses of arnottin i and arnottin II
Moschitto, Matthew J.,Anthony, David R.,Lewis, Chad A.
, p. 3339 - 3342 (2015)
Short total syntheses of arnottin I and II were accomplished in 5 and 6 steps, respectively. A sesamol-benzyne cycloaddition with a 3-furyl-benzoate followed by regiospecific lactonization provided rapid, large-scale access to the core of arnottin I. Saponification of arnottin I and hypervalent iodide mediated spirocyclization provided an efficient and direct preparation of racemic arnottin II.
Total synthesis of 12-methoxydihydrochelerythrine and anti-tumour activity of its quaternary base: toward an efficient synthetic route for 12-alkoxybenzo[c]phenanthridine bases via naphthoquinone monooxime from 2-benzofuranyl-1-tetralone derivative.
Watanabe, Toshiko,Ohashi, Yoshiaki,Yoshino, Rie,Komano, Naoko,Eguchi, Miyuki,Maruyama, Sakiko,Ishikawa, Tsutomu
, p. 3024 - 3032 (2007/10/03)
A concise total synthesis of 12-methoxydihydrochelerythrine (6), isolated from Bocconia integrifolia, is described. The synthesis features an efficient route to a 12-alkoxybenzo[c]phenanthridine skeleton via naphthoquinone monooxime 11 as a key compound. Starting from 7-methoxy-2-methylbenzo[b]furan (9), 3-aryl-1-tetralone 10 was synthesised, followed by aromatisation to 3-aryl-1-naphthol 17. After oxidative cleavage of the furan ring, basic nitrosation of naphthol 22 gave the naphthoquinone 11. The benzo[c]phenanthridine skeleton was formed by reductive cyclisation of 11. Deoxygenation of the lactam moiety in 23 afforded nor-base 32 and methylation of 32 under reductive conditions gave the target dihydro base 6 (23 steps from benzofuran 9 in 10% overall yield). The corresponding quaternary base 7 showed moderate anti-tumour activity against cancer cell lines; on NCI-H460: IC50 4.5 microM and on MDA-MB-231: IC50 1.2 microM. Introduction of a methoxy group into the 12-position of the benzo[c]phenanthridine skeleton could cause enhanced activity against MDA-MB-231 by comparison of 7 with chelerythrine (35) (IC50 5.3 microM).
