(+)-OCTOPINE → HCID 3310216, compound

Participants

Reaction Steps

20 g of D-octopine in 100 ml of 1M NaOH was heated at 100° C. for 12-20 hr. The solution was evaporated to dryness to remove the ammonia and then dissolved in water. The pH was adjusted to 0.89 with 6M HCl and the solution was applied to a column of 200 g of Dowex-50 (H+ -form). The column was washed with water and then developed with 10% (v/v) aqueous ammonium hydroxide. The fractions that contained ninhydrin-positive material after removal of ammonia were combined, evaporated to dryness on a rotary evaporator, and then dissolved in 100 ml of water. The pH was adjusted to 5.2 with 3M HCl. After the addition of 5 volumes of ethanol, the solution was left at 0°-5° C. for 24 to 48 hr. A white solid was collected by filtration in an amount of 11.1 g, and identified as octopinic acid (67% yield, 99% pure). The absence of significant racemization at the chiral carbon atoms is supported by the fact that the product gave a single peak by HPLC in the 80% methanol in water, partisil SAX column solvent system that separates D-octopinic acid from L-allooctopinic acid and by its optical rotation ((α)D22 =20°, C 0.5, H2O; publ. 19°).

Provenance & Evidence