Chromene compound

A chromene compound represented by the following general formula (1),

• 60
• wherein R1 is a substituted amino group, a substituted or unsubstituted heterocyclic group having a nitrogen atom, as a hetero atom, bonded to a naphthopyran ring or a condensed heterocyclic group in which said heterocyclic group is condensed with an aromatic hydrocarbon ring or an aromatic heterocyclic ring,
• R2 is an alkyl group, an alkoxyl group, an aralkoxyl group, an aralkyl group, a substituted amino group, a cyano group, a substituted or unsubstituted aryl group, a halogen atom, a substituted or unsubstituted heterocyclic group having, as a hetero atom, a nitrogen atom, bonded to the naphthopyran ring, or a condensed heterocyclic group in which said heterocyclic group is condensed with an aromatic hydrocarbon ring or an aromatic heterocyclic ring,
• “a” is an integer of 0 to 3,
• X1 is a group represented by the following formula (2),
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• wherein each of R3, R4 and R5 is a hydrogen atom, a substituted amino group, a substituted or unsubstituted heterocyclic group having a nitrogen atom, as a hetero atom, bonded to a benzene ring, or a condensed heterocyclic group in which said heterocyclic group is condensed with an aromatic hydrocarbon ring or an aromatic heterocyclic ring, but R3, R4 and R5 are not hydrogen atoms simultaneously, and
• X2 is a group represented by the following formula (3),
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• wherein R6 is a hydrogen atom;
• an electron attractive group selected from the group consisting of a trifluoromethyl group, a trifluoromethoxy group, a cyano group, a sulfonyl group, an alkylsulfonyl group, an arylsulfonyl group and a nitro group;
• or an alkoxyl group,
• each of R7 and R8 is (i) a hydrogen atom, an aliphatic hydrocarbon group having not less than three carbon atoms, a halogen atom, a trifluoromethyl group, a trifluoromethoxy group, a cyano group, a sulfonyl group, an alkylsulfonyl group, an arylsulfonyl group or a nitro group when R6 is not a hydrogen atom, or (ii) a hydrogen atom, a halogen atom, a trifluoromethyl group or a trifluoromethoxy group when R6 is a hydrogen atom,
• each of R9 and R10 is a hydrogen atom, a cyano group, an alkoxyl group having 1 to 5 carbon atoms, a fluorine atom or a chlorine atom,
• wherein, when R4 in the group represented by the above formula (2) is the substituted amino group, the substituted or unsubstituted heterocyclic group or is the condensed heterocyclic group, R6 is not an alkoxyl group, and R6, R7, R6, R9 and R10 are not hydrogen atoms simultaneously.