4-{N-[2-(1,3-Dioxo-1,3-dihydroisoindol-2-yl)-3-phenylpropionyl]anilino}-1-phenethylpiperidinium chloride methanol disolvate.

The structure of the title compound, a fentanyl derivative with formula C(36)H(36)N(3)O(3) (+)·Cl(-)·2CH(3)OH, crystallizes as a racemic mixture. The organic cation has an extended conformation and the structure displays O-H⋯O, O-H⋯Cl and N-H⋯Cl hydrogen bonding.

Synthesis and evaluation of 3-aminopropionyl substituted fentanyl analogues for opioid activity.

An enkephalin analogue coupled to 'aminofentanyl' has been synthesized and tested for biological activities at the mu and delta opioid receptors. Aminofentanyl which represents a structural derivative of fentanyl has been synthesized by acylation of 1-(2-phenethyl)-4-(N-anilino)piperidine with phthaloyl protected beta-alaninyl chloride in the presence of DIPEA, followed by deprotection with hydrazine hydrate. Aminofentanyl has also been successfully acylated with ethyl isocyanate, various acid anhydrides, to further investigate structure-activity relationships of these new fentanyl derivatives.