A regioselective 6-endo reductive cyclization of 2-indolylacyl radicals constitutes the key step of a straightforward synthetic entry to the olivacine skeleton, illustrated by a total synthesis of the tetrahydropyridine alkaloid guatambuine.
The structure of olivacine and u-alkaloid C (Guatambuine)
作者:Miguel A. Ondetti、Venancio Deulofeu
DOI:10.1016/0040-4020(61)80020-3
日期:1961.1
From A. australe the following alkaloids were isolated: from the aereal bark olivacine and (±) guatambine; from the heartwood, olivacine and a base m.p. 186–188° present in very small amounts; fromrootbark, olivacine, (+) guatambuine (u-alkaloid C), (-) guatambuine and uleine; fromroot heartwood, olivacine. (±) Guatambuine is N-methyl-tetrahydro-olivacine. The products of the Hofmann degradation
known about the biological activities of these compounds. Six synthetic natural alkaloids and five of their derivatives were evaluated for their antiproliferative activity against HCT-116 and HL-60 cells. The activities of variants with the D-reduced ring or without the C(11)-Me group were lower than those of ellipticine. The conformer of guatambuine showed higher activities than guatambuine.