HCID 178435494, compound → HCID 178435492, compound

Participants

Reaction Steps

To a solution of methyl pheophorbide-a (25 g, 42.5 mmol) in pyridine (1 L) was added distilled water (10 mL, 556 mmol, 13 equiv., 1% v/v) and the mixture was refluxed under argon with stirring. The reaction was monitored by HPLC (hexane-acetone, 90:10-mobile phase, LiChrospherCN-column, detection at 425 and 410 nm). An HPLC of the reaction aliquot after 9 hours of reflux showed 99% completion (by peak area). The solution was cooled to room temperature after 10 hours of reflux and solvent removed under reduced pressure. The residue was precipitated first from methylene chloride-hexane and then methylene chloride/methanol. The solid collected was then purified on a silica gel column, eluted with 2% acetone/methylene chloride. The desired fraction was collected and precipitated from methylene chloride/methanol to give methyl pyropheophorbide-a (20.3 g, 91%).

Provenance & Evidence