Reactions of Morphine Derivatives with Phenyliodo(III)Diacetate (PIDA) Synthesis of New Morphine Analogues+,++

The reactions of morphine and its derivatives with phenyliodo(III)diacetate (PIDA) have been studied. This methodology has not been introduced to morphine alkaloids, despite the fact that such a strategy would ensure dearomatization of the electrophilic aromatic ring of morphine derivatives leading to nucleophilic ortho-quinoidal structures with potential pharmacological interest. The products, formed in regio- and diastereoselective or diastereospecific reactions, carry mixed-acetal or 1,3-dioxolane moieties. At low concentrations 6a has μ-opioid agonist character but in higher concentrations showed a non receptorial antagonist effect on isolated mouse vas deferens.