To provide a new compound absorbing the light in a near infrared region, and to provide a method for producing the compound.

There are provided the compound represented by general formula (1) (wherein, R1, R2 and R3 are each independently hydrogen, an aromatic ring group which may have a substituent, or a 0-20C nonaromatic ring substituent, with the proviso that R1 and R2 or R2 and R3 present on the same azulene ring may form a ring by being bonded to each other, and R1s, R2s and R3s each present on the different azulene rings may be each different from each other; M is two hydrogens or a divalent cationic atom; with the proviso that when the cationic atom has tri- or more valent, the molecule may have a ≤20C counter anion more), the isomer thereof, and the method for producing them.

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