A. Kubo, T. Nakai, Yu-ichi Koizumi
1992
Citations
0
Influential Citations
6
Citations
Journal
Heterocycles
Abstract
A simple and efficient synthesis of 4-cyano-8-methoxy-9-methyl-1,3,4,6,11,11a-hexahydro-2H-benzo[b]quinolizine-7,10-dione (20a) as a simple model compound of saframycin A (1) is described starting from the corresponding lactam (16). Reduction of the lactam (16) with lithium aluminum hydride followed by sodium cyanide treatment afforded the α-amino nitrile (19) as an inseparable mixture in an excellent yield. Oxidative demethylation of compound (19) with 10N HNO 3 gave the title compound (20a) and its C-4 epimer (20b). The structure of 20a was confirmed by 1 H nmr and 13 C nmr spectroscopic analysis