PURPOSE: To prepare a new compd. useful as a pharmaceutic for the photodynamic chemotherapy of tumors.

CONSTITUTION: This compd. is expressed by formula I, for example, bis(diphenylcholesteryloxysiloxy)germanium-phthalocyanine. In the formula I, R1, R2 are siloxy such as -[OSi(R5,R6)]m-(O-CH2CH2)n-R7 or the like; R3, R4 are H, lower alkyl, lower alkoxy-substd. 1-26C alkoxy or the like, R5, R6 are lower alkyl or phenyl; R7 is 1-20C alkylthio, 1-20C alkanoyloxy or the like; m is 0 or 1; n is 0 to 200; M is Al, Ge or the like. The compd. expressed by formula I is obtd. by the reaction of a compd. expressed by formula II (R11 is hydroxy or halogen; R12 is same as R11 or not present) and a compd. expressed by R1-H. The obtd. pharmaceutic is suitable for non-oral medication, especially intravenous medication.