Improvement in the method for the preparation of N-(3,4-dimethoxyphenylethyl)-3′,4′-dimethoxyphenylacetamide
The synthesis of I was first described in 1909 [i]. At present several methods are known for the preparation of this compound, starting from 3,4-dimethoxyphenylethylamine (If) and 3,4-dimethoxyphenylacetic acid (III) or its acid chloride (IV) [2-4]. The use of IV makes it possible to obtain I in a yield of up to 95% [5, 6], but this method cannot be used industrially because of considerable complications of the industrial process.
Practical preparation of coralyne chloride.
Abstract Coralyne chloride was prepared by a convenient process which can be adapted to large-scale synthesis of this antileukemic alkaloid.
Total synthesis of ( )-bisnorargemonine.
(±)-Bisnorargemonine (I) was synthesized by two alternate but similar routes, differing only in the relative positions of the methoxy and benzyloxy groups on the aromatic rings of the 1-benzylisoquinoline-derived moieties. Both the standard Bischler-Napieralski procedure and the Pictet-Gams modification were employed in the construction of the needed isoquinoline intermediates. Conversion of the latter to the methiodide followed by partial reduction to the N-methyl-1,2-dihydro form and, finally, acid-catalyzed cyclization provided (±)-I, which was identical with natural (-)-I except for melting point and optical rotatory power.