Disclosed herein is a method for the preparation of diarylmethane dyes and triarylmethane dyes, such as Isosulfan Blue, using electrochemistry. Further disclosed is Isosulfan Blue prepared from a process employing electrochemistry, compositions comprising the same, and use of the prepared Isosulfan Blue as an imaging agent.

Disclosed herein is a method for the preparation of diarylmethane dyes and triarylmethane dyes, such as Isosulfan Blue, using electrochemistry. Further disclosed is Isosulfan Blue prepared from a process employing electrochemistry, compositions comprising the same, and use of the prepared Isosulfan Blue as an imaging agent.

There is provided a compound having a structure represented by the following Formula (1),

##STR00001## in Formula (1), R.sub.1 and R.sub.2 each independently represent a phenyl group having a substituent or an unsubstituted phenyl group, R.sub.3 and R.sub.4 each independently represent a C2-C12 alkyl group having a substituent or an unsubstituted C2-C12 alkyl group, a cyano group, a trifluoromethyl group, or a halogen atom, R.sub.5 and R.sub.6 each independently represent a hydrogen atom or an alkyl group, R.sub.7 represents a phenyl group having a substituent, an unsubstituted phenyl group, or a heteroaromatic group having a specific structure, and X.sup.− represents an anion, and in a case where at least one anionic substituent is included in a molecule, X.sup.− may not be present.

The present invention relates to process for preparation of Isosulfan blue (Formula I) substantially free from desethyl impurity.

The present invention relates to process for preparation of Isosulfan blue (Formula I) substantially free from desethyl impurity.

The present invention relates to process for preparation of Isosulfan blue (Formula I) substantially free from desethyl impurity.

The present invention relates to process for preparation of Isosulfan blue (Formula I) substantially free from desethyl impurity.

A colored composition is provided having higher heat resistance as compared with a conventional colored composition using triarylmethane derivative.

The present invention relates to a compound represented by the following general formula (1), and a polymer having a monomer unit derived from the compound, and the like.

##STR00001##

(wherein R.sub.1 to R.sub.4 each independently represent an alkyl group or the like; R.sub.5 to R.sub.7 each independently represent a hydrogen atom or a methyl group; n pieces of R.sub.8 each independently represent a halogen atom, an alkyl group, an aryl group, a hydroxy group, a nitro group, a sulfo group, an alkoxy group, or the like; and n represents an integer of 0 to 4. A.sub.1 represents an alkylene group, or the like; A.sub.2 represents NH or O. An.sup. represents an anion containing an aryl group having an electron-withdrawing substituent, a sulfonyl group having an electron-withdrawing substituent, or a halogenated alkyl group.)

A colored composition is provided having higher heat resistance as compared with a conventional colored composition using triarylmethane derivative.

The present invention relates to a compound represented by the following general formula (1), and a polymer having a monomer unit derived from the compound, and the like.

##STR00001##

(wherein R.sub.1 to R.sub.4 each independently represent an alkyl group or the like; R.sub.5 to R.sub.7 each independently represent a hydrogen atom or a methyl group; n pieces of R.sub.8 each independently represent a halogen atom, an alkyl group, an aryl group, a hydroxy group, a nitro group, a sulfo group, an alkoxy group, or the like; and n represents an integer of 0 to 4. A.sub.1 represents an alkylene group, or the like; A.sub.2 represents NH or O. An.sup. represents an anion containing an aryl group having an electron-withdrawing substituent, a sulfonyl group having an electron-withdrawing substituent, or a halogenated alkyl group.)