Narcotine and Related Compounds

A facile conversion of (—)-a-narcotine to the alkaloid nornarceine involves Hofmann elimination of A-benzyl-( —)-a-narcotinium bromide (21) followed by ethanolysis. The resulting ester 22 was debenzylated and saponified in good yield.  

In similar fashion, (—)-j8-hydrastine (23) is a source of the amino acid 24 which has been taken to the aporhoeadane 25  

When ( —)-a-narcotine 7V-oxide is allowed to stand in chloroform or is pyrolyzed, the product is a crystalline material which was erroneously labeled anhydro-A -oxynornarceine. This compound has now been shown to possess structure 26 through X-ray analysis of the bromo derivative 27. (—)-j3-Hydra-stine iV-oxide undergoes a similar rearrangement.  

Thermal decomposition of narceine imide methiodide in the presence of 30% potassium hydroxide yields the Hofmann products 28 and 29, as well as the aporhoeadane derivative 30 which can be further reduced to 31 and 32  

In contrast, thermal decomposition of narceine imide methohydroxide gives a 55% yield of 28 and 29, as well as a small amount of the rearranged lactam 33.  

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