Studies on the Syntheses of 7, 8-Disubstituted 1-Benzylisoquinoline and Related Compounds. (2). Syntheses of dl-Cularimine and dl-Cularine

Abstract

Bischler-Napieralski reaction of phenolic amide (V), which was obtained by condensation of 3-benzyloxy-4-methoxyphenethylamine and methyl 2-bromo-4, 5-dimethoxyphenyl-acetate followed by bromination, afforded the isoquinoline derivative (VI), which was further reduced with sodium borohydride to the 1, 2, 3, 4-tetrahydroisoquinoline compound (III). Intramolecular Ullmann reaction of III in the presence of potassium carbonate and cupric oxide in pyridine gave the expected compound (VII) which, on debromination with lithium aluminum hydride, gave dl-cularimine. Similarly, dl-cularine was synthesized from III by subsequent N-methylation, Ullmann reaction, and debromination.