Abstract: A compound represented by the following general formula (I) or a salt thereof [R1 represents hydrogen atom, or a C1-12 alkyl group; R2 represents a C1-12 alkyl group having one or more maleimide groups, an aryl group having two or more maleimide groups, a group represented by the formula (A): —(CH2)n—CO—N(R11)(R12) (R11 and R12 represent hydrogen atom, a C1-12 alkyl group, a C1-12 alkyl group having one or more maleimide groups, or an aryl group having one or more maleimide groups, and n represents an integer of 1 to 6), or a group represented by the formula (B): —(CH2)m—NH—CO—R13 (R13 represents a C1-12 alkyl group having one or more maleimide groups, or an aryl group having one or more maleimide groups, and m represents an integer of 1 to 6); R3 and R5 represent hydrogen atom, or a halogen atom; R4 represents hydroxyl group, a C1-12 acyloxy group, a C1-12 acyloxymethyloxy group, or an amino group], which is useful as a novel fluorescent labeling agent having a property of emitting intense fluorescence only

Abstract: A compound represented by the following general formula (I) or a salt thereof: [wherein R1 and R2 represent hydrogen atom, a C1-6 alkyl group, or a group represented by the following formula (A): [wherein X1 and X2 represent hydrogen atom, or a group represented as —N(R3)(R4) (R3 and R4 represent hydrogen atom, a C1-6 alkyl group, a C1-6 alkylcarbonyl group, or a C1-6 alkyloxycarbonyl group); and n represents an integer of 1 to 6], provided that R1 and R2 do not simultaneously represent hydrogen atom), which is a novel luciferin derivative that serves as a luciferase substrate.

Abstract: A photodegradable protective group comprising a benzyl group which is bound with a light capturing moiety that can absorb light of around 470 nm and having one or more nitro groups on the benzene ring.

Abstract: A compound represented by the formula (I) wherein R1 and R2 represent amino groups that substitute at adjacent positions on the benzene ring, wherein one of the amino groups may have one alkyl group; R3 and R4 represent hydrogen atom, a C1-6 alkyl group, or a C1-6 alkoxy group, R5 and R8 independently represent a C1-6 alkyl group, R6 and R9 represent a carboxy-substituted C1-6 alkyl group, an alkoxycarbonyl-substituted C1-6 alkyl group, a sulfo-substituted C1-6 alkyl group, or an alkyl sulfonate-substituted C1-6 alkyl group, and R7 and R10 represent a C1-6 alkyl group, an aryl group, a C1-6 alkoxycarbonyl group, a vinyl group, a thienyl group, or a pyrrolyl group, and an agent for measurement of nitrogen monoxide containing the compound. Said compound can give a fluorescent substance that is free from change in fluorescence intensity in a wide pH range.

Abstract: A reagent for measuring peroxynitrite comprising a compound represented by the following general formula (I): wherein R1 represents an amino group, or hydroxy group; R2 represents a 2-carboxyphenyl group; and X1 and X2 independently represent hydrogen atom, or a halogen atom (e.g., 2-[6-(4?-hydroxy)phenoxy -3H-xanthen-3-on-9-yl]benzoic acid, or 2-[6-(4?-amino)phenoxy-3H-xanthen-3-on-9-yl]benzoic acid) or a salt thereof, which does not react with superoxide or nitrogen monoxide, a precursor of peroxynitrite, and specifically reacts with peroxynitrite.

Abstract: A compound represented by general formula (I) or (II) or a salt thereof and an agent for measurement of a reactive oxygen comprising said compound or a salt thereof: wherein R1 and R2 independently represent an aryl group which may be substituted, e.g., a phenyl group substituted with an amino group or a hydroxy group, and R3 represents a 2-carboxyphenyl group which may be substituted.

Abstract: A fluorescent probe which is represented by the following formula (I): (wherein, R1 and R2 represent hydrogen atom, or a substituent for trapping proton, a metal ion, or an active oxygen species, or the like; R3 represents a monovalent substituent; R4 and R5 represent hydrogen atom or a halogen atom; R6 represents hydrogen atom, an alkylcarbonyl group, or an alkylcarbonyloxymethyl group, provided that a combination of R1, R2, and R3 provides (1) substantially high electron density of the benzene ring to which said groups bind, so that the compound represented by the formula (I) is substantially no fluorescent before the trapping of proton, or the like, and (2) substantially reduced electron density of the benzene ring to which said groups bind, so that a compound after the trapping, which is derived from the compound represented by the formula (I) is substantially highly fluorescent after the trapping of proton or the like). A fluorescent probe having an excellent fluorescence property is provided.

Abstract: Compounds useful as agents for measurement of singlet oxygen, which are represented by the following general formula (I): wherein R1, R2, R3, R4, R5, and R6 independently represent a hydrogen atom, a halogen atom, a C1-6 alkyl group, or a C1-6alkoxyl group, R7 and R8 independently represent a C1-4alkyl group, and R9 represents a hydrogen atom, a C1-12 alkanoyl group, or acetoxymethyl group, or salts thereof.

Abstract: A method for measuring hypochlorite ion, which comprises the steps of:

Abstract: Compounds useful as agents for measurement of singlet oxygen, which are represented by the following general formula (I): 1

Abstract: A compound represented by general formula (I) or (II) or a salt thereof and an agent for measurement of a reactive oxygen comprising said compound or a salt thereof: 1