Radiation protection drug containing tocopherol or tocotrienol compound ester derivative as active ingredient

1. A method for treating or reducing side effects caused by exposure to radiotherapy or radiodiagnosis, which comprises administering to a patient in need thereof, a therapeutically effective amount of a compound represented by the general formula (I) or a pharmaceutically acceptable salt thereof:

wherein Q is a group represented by formula

R 1 is a methyl group;

R 2 is a group (i) represented by general formula:

(R) 2 N(CH 2 ) 1 CO—

(wherein each of the two Rs, which may be the same or different, is a hydrogen atom or a C 1-4 alkyl group, and l is 1 to 4), or

(R 5 ) 2 N(CH 2 ) m CO—  (3)

(wherein each of the two R 5 s, which may be the same or different, is a hydrogen atom or a C 1-4 alkyl group, and m is 0 to 3);

a group (ii) represented by general formula:

(wherein n is 0 to 2, R is as defined above, and R′ is a side chain of an amino acid selected from the group consisting of alanine, arginine, valine, leucine, isoleucine, asparagine, aspartic acid, glutamine, glutamic acid, phenylalanine, methionine, cysteine, serine, threonine, tyrosine, proline, hydroxyproline, histidine and lysine); or

a group (iii) represented by general formula:

(wherein each of the two Ys, which may be the same or different, is —OH, —O − , or —OA wherein A is an alkali metal); and

each of R 3 and R 4 , which may be the same or different, is a hydrogen atom or a C 1-4 alkyl group.

2. The method as claimed in claim 1 , wherein said compound represented by the general formula (I) is d-α-tocopherol N,N-dimethylglycine ester, d-γ-tocotrienol N,N-dimethylglycine ester, d-α-tocotrienol N,N-dimethylglycine ester, d-γ-tocopherol phosphate disodium salt, dl-α-tocopherol phosphate disodium salt, or d-γ-tocopherol N-methyl-L-proline ester.