The preparation of a selection of novel opioid alkaloids based on alteration at the 1, 3 and 6 positions of codeine and morphine has been achieved. Herein we present the synthetic methodology, structural characterisation and biological evaluation of these novel opioid species.
A range of opioid derivatives with modification at the 6 position to form linked bis-opioid species were successfully synthesised. The derived compounds contain both ester and ether linked moieties. A selection of derivatives with modification at the 1 position of codeine were also generated through Heck, Stille and Suzuki palladium catalysed carbon-carbon coupling. A combination of both synthetic approaches has led to a variety of opioid species with modification at both the 1 and 6 positions.
A selection of the opioid species generated were analysed for their binding affinity to the mu opioid receptor through radioligand binding techniques. Binding affinities of a variety of the opioid species to a selection of metals were also assessed by metal picrate extraction studies.