An adenine compound useful as a medicine represented by the following formula (1):
[wherein R
1
is halogen atom, optionally substituted alkyl group, optionally substituted aryl group, etc.;
X is oxygen atom, sulfur atom, a single bond, etc.;
A
1
is optionally substituted and optionally saturated 4 to 8 membered heterocyclic group containing 1 to 2 hetero atoms selected from 1 to 3 nitrogen atoms, 0 to 1 oxygen atom, and 0 to 1 sulfur atom;
A
2
is optionally substituted 6 to 10 cyclic aromatic hydrocarbon group or optionally substituted 5 to 10 membered heterocyclic aromatic group;
L
1
and L
2
are independently, substituted straight or branched alkylene or a single bond, etc.;
L
3
is optionally substituted straight or branched alkylene, etc.;
R
2
is hydrogen atom, optionally substituted alkyl group.]
or its pharmaceutically acceptable salt.