PURPOSE: To provide an opioid decomposing enzyme-inhibiting agent containing a specific γ-lactone type organic germanium compound as an active ingredient and exhibiting a strong inhibiting action on a specific opioid-decomposing enzyme even in an extremely low concentration.
CONSTITUTION: This opioid decomposing enzyme-inhibiting agent contains an organic germanium compound of formula (1) [R1 is alkyl such as methyl or ethyl; R2-R4 are H, R1, (substituted)phenyl] (e.g. compounds of formulas 6, 7 and 8) as an active ingredient. The opioid decomposing enzyme-inhibiting agent is an excellent medicine permitting to effectively utilize administered morphine, etc., in vivo and further reduce the dosage of the strongly addictive morphine, etc. The organic germanium compound is obtained e.g. by reacting a trihalogenogermylpropionic acid derivative of formula (2) with a Grignard reagent of formula (3), reacting the produced compound of formula (4) with bromine, etc., to cut the Ge-R1 bond and simultaneously brominating the Ge, and finally hydrolyzing the produced monobromo compound of formula (5).
KATAYAMA TAKASHI
HASATO TADAHIKO
MORI MASATO
