Hydrochloric Acid → N-(3-carboxypropyl)-N-methyl-L-valyl-N-[(3R,4S,5S)-3-methoxy-1-{(2S)-2-[(1R,2R)-1-methoxy-2-methyl-3-{[(2S)-1-(1-naphthylmethoxy)-1-oxo-3-phenylpropane-2-yl]amino}-3-oxopropyl]pyrrolidin-1-yl}-5-methyl-1-oxoheptan-4-yl]-N-methyl-L-valinamide

Participants

Reaction Conditions

Reaction Steps

24 mg (24 μmol) of N-methyl-L-valyl-N-[(3R,4S,5S)-3-methoxy-1-{(2S)-2-[(1R,2R)-1-methoxy-2-methyl-3-{[(2S)-1-(1-naphthylmethoxy)-1-oxo-3-phenylpropane-2-yl]amino}-3-oxopropyl]pyrrolidin-1-yl}-5-methyl-1-oxoheptan-4-yl]-N-methyl-L-valinamide sodium trifluoroacetate (intermediate 21) and 31.5 μl of 15% aqueous amber aldehyde acid solution (49 μmol) were dissolved in 900 μl of a 1:1-dioxane/water composition and heated for 1 hour at a temperature of 100° C. After a short cooling period 1.7 mg (27 μmol) of sodium cyanoborohydride were added. The reaction composition was formulated with 0.1 of N hydrochloric acid to pH 3 and heated for 2 hours at a temperature of 100° C. It was reheated again for 2 hours at 100° C. after the same amounts of amber aldehyde acid solution, sodium cyanoborohydride, and hydrochloric acid had been added once again. Afterwards, the reaction composition had been separated directly by means of preparative HPLC. The yield was 20.1 mg (86% o. th.) of the title compound.

Provenance & Evidence