A compound of the formula: or a pharmacologically acceptable salt thereof, wherein R A represents a hydrogen atom, a halogen atom, NH 2 or NH(C 1-3 alkyl); X 1 represents CH or N; L is a group represented by formula (L-1), (L-2) or (L-3): wherein R L1, R L2 and R L3 each, independently of one another, represents a hydrogen atom, F, Cl; or a (C 1 -C 3)alkyl group, which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; Y 1 and Y 2 each, independently of one another, is NH, O, or S; each " ", independently of one another, represents a single bond or a double bond, wherein at least one " " in the ring of formula (L-3) is a double bond; T 1 is a hydrogen atom; and T 2 represents a hydrogen atom; or an aryl, heteroaryl, aralkyl or heteroaralkyl group, all of which groups may be substituted by one, two or more, identical or different, group(s) selected from: a halogen atom, OH, =O, NH 2, (C 1 -C 3)alkyl which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; (C 1 -C 3)alkoxy which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; and C NR T1 R T2; R T1 and R T2 each, independently of one another, represents a hydrogen atom or a (C 1 -C 3)alkyl group, which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; or T 1 and T 2 both represent O. R A represents a hydrogen atom, a halogen atom, NH 2 or NH(C 1-3 alkyl); X 1 represents CH or N; L is a group represented by formula (L-1), (L-2) or (L-3): wherein R L1, R L2 and R L3 each, independently of one another, represents a hydrogen atom, F, Cl; or a (C 1 -C 3)alkyl group, which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; Y 1 and Y 2 each, independently of one another, is NH, O, or S; each " ", independently of one another, represents a single bond or a double bond, wherein at least one " " in the ring of formula (L-3) is a double bond; R L1, R L2 and R L3 each, independently of one another, represents a hydrogen atom, F, Cl; or a (C 1 -C 3)alkyl group, which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; Y 1 and Y 2 each, independently of one another, is NH, O, or S; each " ", independently of one another, represents a single bond or a double bond, wherein at least one " " in the ring of formula (L-3) is a double bond; T 1 is a hydrogen atom; and T 2 represents a hydrogen atom; or an aryl, heteroaryl, aralkyl or heteroaralkyl group, all of which groups may be substituted by one, two or more, identical or different, group(s) selected from: a halogen atom, OH, =O, NH 2, (C 1 -C 3)alkyl which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; (C 1 -C 3)alkoxy which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; and C NR T1 R T2; R T1 and R T2 each, independently of one another, represents a hydrogen atom or a (C 1 -C 3)alkyl group, which may be substituted by one or more, identical or different, group(s) selected from a halogen atom, OH, =O, and NH 2; or T 1 and T 2 both represent O.