An ink set includes: a magenta ink composition; a cyan ink composition; a yellow ink composition; and a black ink composition, in which the magenta ink composition contains at least one compound represented by the general formula (1) as defined herein, the cyan ink composition contains at least one compound represented by the general formula (2) as defined herein, the yellow ink composition contains at least one compound selected from the group Y as defined herein, and the black ink composition contains at least one black pigment dispersion liquid including carbon black.

An ink set includes a magenta ink composition; a cyan ink composition; a yellow ink composition; and a black ink composition, in which the magenta ink composition contains at least one compound represented by the general formula (1) as defined herein, the cyan ink composition contains at least one compound represented by the general formula (2) as defined herein, the yellow ink composition contains at least one compound selected from the group Y as defined herein, and the black ink composition contains at least one compound selected from the group BK as defined herein.

An ink set includes a magenta ink composition; a cyan ink composition; a yellow ink composition; and a black ink composition, in which the magenta ink composition contains at least one compound represented by the general formula (1) as defined herein, the cyan ink composition contains at least one compound represented by the general formula (2) as defined herein, the yellow ink composition contains at least one compound selected from the group Y as defined herein, and the black ink composition contains at least one compound selected from the group BK as defined herein.

[Problem to be Solved] To provide a fluorescent probe for ALDH3A1 detection that can be used in flow cytometry adaptable to live cells.

[Means of Resolution] A compound represented by general formula (I) or a salt thereof, wherein the compound or salt thereof has a retention time on an HPLC chromatogram measured under the following conditions of longer than 6.9 minutes when said compound is in aldehyde form and of 6.9 minutes or less when said compound is in carboxylic acid form.

[Problem to be Solved] To provide a fluorescent probe for ALDH3A1 detection that can be used in flow cytometry adaptable to live cells.

[Means of Resolution] A compound represented by general formula (I) or a salt thereof, wherein the compound or salt thereof has a retention time on an HPLC chromatogram measured under the following conditions of longer than 6.9 minutes when said compound is in aldehyde form and of 6.9 minutes or less when said compound is in carboxylic acid form.

A method of quenching excited state energy from a photodegradable pigment that has been excited by absorption of light having a wavelength in the wavelength range of 290-800 nm, comprising reacting a pigment with a conjugated fused tricyclic compound having electron withdrawing groups of Formula (II) or a salt thereof: ##STR00001## wherein: A is selected from the group consisting of O, S, CO, CS, ##STR00002## B.sup.1, B.sup.2, D.sup.1 and D.sup.2 are each independently selected from the group consisting of F, Cl, Br, I, CF.sub.3, CC13, NR33+, NO2, CN, C(O)R4, C(O)OR, SO2R5, aryl, and CCHR6; each m independently is 0, 1, 2, 3, or 4; a is 0 or 1; each R is independently selected from the group consisting of LI, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl; R.sup.2 is selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, alkynyl, and aryl; each R.sup.3 is independently selected from the group consisting of H and C.sub.1-C.sub.6 alkyl; each R.sup.4 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl; each R.sup.5 is independently selected from the group consisting of H, O, OH, NH.sub.2, and Cl; and each R.sup.6 is-independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl.

A method of quenching excited state energy from a photodegradable pigment that has been excited by absorption of light having a wavelength in the wavelength range of 290-800 nm, comprising reacting a pigment with a conjugated fused tricyclic compound having electron withdrawing groups of Formula (II) or a salt thereof: ##STR00001## wherein: A is selected from the group consisting of O, S, CO, CS, ##STR00002## B.sup.1, B.sup.2, D.sup.1 and D.sup.2 are each independently selected from the group consisting of F, Cl, Br, I, CF.sub.3, CC13, NR33+, NO2, CN, C(O)R4, C(O)OR, SO2R5, aryl, and CCHR6; each m independently is 0, 1, 2, 3, or 4; a is 0 or 1; each R is independently selected from the group consisting of LI, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl; R.sup.2 is selected from the group consisting of H, alkyl, cycloalkyl, alkenyl, alkynyl, and aryl; each R.sup.3 is independently selected from the group consisting of H and C.sub.1-C.sub.6 alkyl; each R.sup.4 is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl; each R.sup.5 is independently selected from the group consisting of H, O, OH, NH.sub.2, and Cl; and each R.sup.6 is-independently selected from the group consisting of alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and aryl.

[Problem]

A problem addressed by the present invention is to provide a novel fluorescent probe having excellent tissue permeability that is capable of detecting the peptidase activity expressed at a high level in cancer cells and the like as a response of long-wavelength red fluorescence.

[Solution]

A compound represented by formula (I) or a salt thereof:

##STR00001##

[In the formula, A represents a ring structure selected from the group consisting of a thiophene ring, a cyclopentene ring, a cyclopentadiene ring, and a furan ring; X represents a C.sub.0-C.sub.3 alkylene group; Y represents O, S, C(O)O, or NH, Z represents O, C(R.sup.a) (R.sup.b), Si(R.sup.a) (R.sup.b), Ge(R.sup.a) (R.sup.b), Sn(R.sup.a) (R.sup.b), Se, P(R.sup.c), or P(R.sup.c) (O) (where R.sup.a and R.sup.b each independently represent a hydrogen atom or an alkyl group, and R.sup.c represents a hydrogen atom, an alkyl group, or an aryl group); R.sup.1 and R.sup.2 each independently represent from one to three of the same or different substituents selected from the group consisting of a hydrogen atom, a hydroxyl group, a halogen atom, and an alkyl group, a sulfo group, a carboxyl group, an ester group, an amide group, and an azide group each of which may be substituted; R.sup.3 represents an acyl residue derived from an amino acid (where the acyl residue is a residue obtained by removing an OH group from a carboxyl group of the amino acid); R.sup.4 and R.sup.5 each independently represent a hydrogen atom or an alkyl group (where when R.sup.4 or R.sup.5 is an alkyl group, the R.sup.4 or R.sup.5, together with R.sup.2, may form a ring structure comprising a nitrogen atom to which R.sup.4 and R.sup.5 are bonded).]

A near-infrared fluorescent probe has fluorescence in the near-infrared region. Like CaSiR-1, the probe has rhodamines as the fluorescent mother nucleus and accumulates in the cytoplasm. The probe makes it possible to visualize concentration fluctuations in metal ions, such as calcium ions, within the body. The fluorescent probe includes a compound represented by the following general formula or a salt of the compound:

##STR00001##

The present specification relates to a method for preparing a colorant composition comprising dissolving a first xanthene-based dye having the same number of positive charges and negative charges and a second xanthene-based dye having more negative charges than positive charges by one or more in a first solvent; and precipitating the dissolved first xanthene-based dye and the dissolved second xanthene-based dye in a second solvent, and a colorant composition, a colorant dispersion, a photosensitive resin composition, a color filter and a liquid crystal display device.