10-Keto opiates

Morphine alkaloids: History, biology, and synthesis

This chapter provides a short overview of the history of morphine since it's isolation by Sertürner in 1805. The biosynthesis of the title alkaloid as well as all total and formal syntheses of morphine and codeine published after 1996 are discussed in detail. The last section of this chapter provides a detailed overview of medicinally relevant derivatives of the title alkaloid.

Chemoenzymatic Total Synthesis of (+)-10-Keto-Oxycodone from Phenethyl Acetate

The total synthesis of (+)-10-keto-oxycodone was attained from phenethyl acetate in a stereoselective manner. Absolute stereochemistry was established via enzymatic dihydroxylation of phenethyl acetate with the recombinant strain JM109 (pDTG601A) that furnished the corresponding cis-cyclohexadienediol whose configuration corresponds to the absolute stereochemistry of the ring C of (+)-10-keto-oxycodone. Intramolecular Heck reaction was utilized to establish the quaternary carbon at C-13, along with the dibenzodihydrofuran functionality. The C-14 hydroxyl and C-10 ketone were installed via SmI₂-mediated radical cyclization, and oxidation of a benzylic alcohol (obtained from an intermediate nitrate azide), respectively. The synthesis of (+)-10-keto-oxycodone was completed in a total of 14 operations (21 steps) and an overall yield of ~2%. Experimental and spectral data are provided for key intermediates and new compounds.

U-50,488 and the kappa receptor: a personalized account covering the period 1973 to 1990

All clinically significant analgesics for severe pain derive from the morphine model. Morphine has provided a fertile area for medicinal chemistry research and received an additional stimulus in the 1970s with the appearance of the opioid receptors. The background for the birth of U-50,488 is described herein. It occurred before the discovery of the kappa receptor and, thus, U-50,488 was classified originally as a non-mu compound, and only later as a kappa agonist. U-50,488 provided a succinct template for structural modifications and they are described for the period up to 1990. A description of the structural classes of kappa agonists is provided including a summary of kappa recognition sites based on known agonists.