TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation: No general preparation is given. Preferred Solvent: The halogen containing solvent is halogen-containing hydrocarbon, and contains chlorine atom or fluorine atom, preferably chlorine atom. Preferably, the solvent is methylene chloride, chloroform, carbon tetrachloride, dichloroethane, trichloroethane, chlorobenzene, dichlorobenzene or trichlorobenzene. Preferred Definitions:    A=monovalent group of formula (II-V);    B'=group of formula (II'-V');    C',C''=group of formula (II''-V'');    A'=bivalent group of formula (II'''-V''');    B''=bivalent group of formula (II''''-V'''');    R20, R26, R35, R20', R26', R35', R20'', R26'', R35'', R20''', R26''', R35''', R20'''', R26'''', R35''''=1-12C hydrocarbyl;    R21, R22, R21', R22', R21'', R22'', R21''', R22''', R21'''', R22''''=H or 1-12C hydrocarbyl;    R23-R25, R27-R34,R36-R39, R23'-R25', R27'-R34',R36'-R39', R23'''-R25''', R27'''-R34''', R36'''-R39''', R23''''-R25'''', R27''''-R34'''', R36''''-R39''''=H, or 1-12C hydrocarbyl optionally having oxy group or amino group;    R23''-R25'', R27''-R34'', R36''-R39''=H, 1-12C hydrocarbyl or group having -CO2H, -SO3H or -PO3H2, 1 or more of R23''-R25'', R27''-R30''and R36''-R39''are group having -CO2H, -SO3H or -PO3H2, preferably -CO2H, -SO3H or -PO3H2;    X,X',X'',X''',X''''=carbon atom, trivalent or tetravalent nitrogen atom, divalent or trivalent sulfur atom, divalent or trivalent oxygen atom, or divalent or trivalent selenium atom;    R4-R7=O-;    o=0;and    p=1.    . When X is trivalent nitrogen atom, R21 does not exist. When X is divalent or trivalent oxygen atom, divalent or trivalent sulfur atom or divalent or trivalent selenium atom, R21 and R22 do not exist. When X'is trivalent nitrogen atom, R22'does not exist. When X'is divalent or trivalent oxygen atom, divalent or trivalent sulfur atom or divalent or trivalent selenium atom, R21'and R22'do not exist. When X''is trivalent nitrogen atom, R22''does not exist. When X''is divalent or trivalent oxygen atom, divalent or trivalent sulfur atom or divalent or trivalent selenium atom, R21''and R22''do not exist. When X'''is trivalent nitrogen atom, R22'''does not exist. When X'''is divalent or trivalent oxygen atom, divalent or trivalent sulfur atom or divalent or trivalent selenium atom, R21'''and R22'''do not exist. When X''''is trivalent nitrogen atom, R22''''does not exist. When X''''is divalent or trivalent oxygen atom, divalent or trivalent sulfur atom or divalent or trivalent selenium atom, R21''''and R22''''do not exist.    SPECIFIC COMPOUNDS - 23 Specific conjugated compounds such as 1-butyl-2-(((1E)-3-((2E)-1-butyl-2-(((3E)-3-((3-butyl-2,3-dihydro-1,3-benzothiazol-3-ium-2-yl)methylidene)-2-oxido-4-oxocyclobut-1-en-1-yl)methylidene)-3,3-dimethyl-2,3-dihydro-1H-indol-5-yl)-2-oxido-4-oxocyclobut-2-en-1-ylidene)methyl)-5-carboxy-3,3-dimethyl-3H-indol-1-ium of formula (Ia-I-6), 1-butyl-2-((3-(1-butyl-2-((3-((1-butyl-3,3-dimethyl-3H-indol-1-ium-2-yl)methylidene)-2-oxido-4-oxocyclobut-1-en-1-yl)methylidene)-3,3-dimethyl-2,3-dihydro-1H-indol-5-yl)-2-oxido-4-oxocyclobut-2-en-1-ylidene)methyl)-5-carboxy-3,3-dimethyl-3H-indol-1-ium, 3-butyl-2-((3-((1-butyl-5-(3-((1-butyl-3,3,5-trimethyl-3H-indol-1-ium-2-yl)methylidene)-2-oxido-4-oxocyclobut-1-en-1-yl)-3,3-dimethyl-2,3-dihydro-1H-indol-2-ylidene)methyl)-2-oxido-4-oxocyclobut-2-en-1-ylidene)methyl)-1,3-benzothiazol-3-ium, 1-butyl-2-((3-(3-butyl-2-((3-((3-butyl-1,3-benzothiazol-3-ium-2-yl)methylidene)-2-oxido-4-oxocyclobut-1-en-1-yl)methylidene)-2,3-dihydro-1,3-benzothiazol-6-yl)-2-oxido-4-oxocyclobut-2-en-1-ylidene)methyl)-5-carboxy-3,3-dimethyl-3H-indol-1-ium, and 3-butyl-2-((3-(3-butyl-2-((3-((3-butyl-1,3-benzothiazol-3-ium-2-yl)methylidene)-2-oxido-4-oxocyclobut-1-en-1-yl)methylidene)-2,3-dihydro-1,3-benzothiazol-6-yl)-2-oxido-4-oxocyclobut-2-en-1-ylidene)methyl)-6-carboxy-1,3-benzothiazol-3-ium are disclosed.    EXAMPLE - 3-Butyl-2-(((1E)-3-(((2E)-1-butyl-5-(3,4-dioxo-2-(propan-2-yloxy)cyclobut-1-en-1-yl)-3,3-dimethyl-2,3-dihydro-1H-indol-2-ylidene)methyl)-2-oxido-4-oxocyclobut-2-en-1-ylidene)methyl)-2,3-dihydro-1,3-benzothiazol-3-ium (in g) (1.6), tetrahydro furan (150 ml) and 3.6% hydrochloric acid (50 ml) were dispersed, to obtain 3-butyl-2-(((1E)-3-(((2E)-1-butyl-5-(2-hydroxy-3,4-dioxocyclobut-1-en-1-yl)-3,3-dimethyl-2,3-dihydro-1H-indol-2-ylidene)methyl)-2-oxido-4-oxocyclobut-2-en-1-ylidene)methyl)-2,3-dihydro-1,3-benzothiazol-3-ium. The obtained compound (0.1) and 1-butyl-5-carboxy-2,3,3-trimethyl indolenium iodide (0.08) were dissolved in n-butanol (4 ml) and benzene (1 ml) and reacted in presence of quinoline as catalyst at 70 degrees C for 3 hours. The solvent was distilled off. The obtained solid was purified and recrystallized to obtain conjugated compound of formula (Ia-I-6), a yield rate of 30%.