PURPOSE: To obtain a chemically stable fat emulsion containing PGI2 derivative, a specific ester derivative of prostaglandin I2 (PGI2) and capable of developing pharmacodynamic effects comparable to those of the PGI2 itself.
CONSTITUTION: A fat emulsion containing a PGI2 derivative, e.g. butoxycarbonylmethyl PGI2 ester expressed by formula I (R1 is 1-20C alkyl; R2 is H or lower alkyl; X is formula II). The aforementioned fat emulsion is prepared by reacting PGI2 with an ester compound expressed by formula III (X2 is halogen), e.g. butyl iodoacetate in the presence of a solvent such as an alcohol or tetrahydrofuran at about 0°C to ambient temperature, providing the compound expressed by formula I and using a well-known vegetable oil, a phospholipid, an emulsification assistant, stabilizer, a polymeric substance, an isotonizing agent, etc., according to a well-known means.
NAITO YOICHIRO
YOKOYAMA KAZUMASA
