NEW MATERIAL:A platinum complex expressed by formula I and optically active isomer thereof.

USE: A synthetic intermediate for carcinostatic agents.

PREPARATION: A platinum (II) potassium chloride expressed by the formula K2PtCl4 and potassium thiocyanate expressed by the formula KSCN in a molar amount of preferably 4 times based on the platinum (II) potassium chloride are dissolved in water and reacted at 0W100°C, preferably 20W80°C, normally for 0.5W5hr while stirring to give a reaction product. 2-Aminomethylpyrrolidine expressed by formula II or an optically active isomer thereof in an amount equimolar with the above-mentioned platinum compound and the reaction mixture is stirred, preferably at 0W100°C for 0.5W10hr to collect the resultant solid by filtration. The solid is then washed with water and dried at 0W80°C under reduced pressure.