Pharmacological Activity and Stereochemistry

Racemic 5b and 5d exhibited analgesic activity equivalent to that of morphine (sc, MHP) with a significant reduction in overall toxicity. Oral 

A comparison of the absolute configurations of (-)-5b and morphine is not possible because of the difference in the orientation of their aromatic rings. Cochran 7) investigated the absolute configuration of (—)-5-(3-hydroxyphenyl)-2-methylmorphan by single-crystal, X-ray analysis of the HBr salt and found it to be 1R, 5S. He discovered that both rings of the morphan-fused system existed in chair conformations with the 2-methyl and 5-aryl substituents equatorial. 

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