Purification of a Water-Sensitive Natural Product with an Aprotic CPC Solvent System

Abstract

The partition coefficients of arachidonic acid (AA), prostaglandin (PG) H₂ and PGE₂ in the binary acetonitrile-hexane two-phase solvent system can be favorably modified by addition of diethyl ether. In the ternary two-phase solvent system acetonitrile-hexane-diethyl ether the partition coefficients of AA and the prostaglandins diverge as the ratio of ether to acetonitrile-hexane (1:1) is increased from 0.00 to 0.15 while the partition coefficients of PGH₂ and PGE₂ diverge as the ratio of ether to acetonitrile-hexane (1:1) is increased from 0.15 to 0.30. Isolation by CPC of PGH₂ from the AA bioconversion reaction mixture is described.