Phosphoric Acid → HCID 67340740, compound

Participants

Reaction Conditions

Reaction Steps

Analogously as described for Example 35 acidic acid (2R,4aR,10bR)-6-(6-cyano-pyridin-3-yl)-9-ethoxy-8-methoxy-1,2,3,4,4a,10b-hexahydro-phenanthridin-2-yl ester (compound 172) is converted in a first step into the corresponding imino ester 5-((2R,4aR,10bR)-9-ethoxy-2-hydroxy-8-methoxy-1,2,3,4,4a,10b-hexahydro-phenanthridin-6-yl)-pyridine-2-carboximidic acid methyl ester. In a second step, 443 mg (1.08 mmol) of 5-((2R,4aR,10bR)-9-ethoxy-2-hydroxy-8-methoxy-1,2,3,4,4a,10b-hexahydro-phenanthridin-6-yl)-pyridine-2-carboximidic acid methyl ester are dissolved in 3 ml of THF. A solution of 51 mg (2.16 mmol) LiOH.H2O is added and the solution stirred at 60° C. for 18 hrs. The pH is adjusted to 5 using phosphoric acid and Disodiumhydrogenphosphate. The solvent is removed and the solid residue extracted with chloroform/methanol. After filtering off and re-moving the volatiles 350 mg (82%) of the title compound are obtained.

Provenance & Evidence