TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Disclosed): Ketone-type compound of formula (II) is processed in presence of phosphoryl trichloride, dimethylformamide and base to obtain an aldehyde intermediate of formula (III). The obtained aldehyde intermediate (III) is reacted with indole-type compound of formula (IV) in presence of methyl alcohol, acetic anhydride and sodium acetate to obtain cyanine-type compound (I).Y'=chloro or hydroxy;R14,R15=1-10C alkyl, 6-30C aryl or 7-30C arylalkyl;andR14+R15=ring.Preferred Compound: The cyanine-type compound (I) is preferably of formula (V), more preferably of formula (VI). SPECIFIC COMPOUNDS - 28 Cyanine-type compounds e.g. 1-butyl-2-((1E,3Z)-5-(1-butyl-1H-benzo(cd)indol-(2E)-ylidene)-3-(4-fluoro-phenyl)-penta-1,3-dienyl)-benzo(cd)indole of formula (IA), 1-butyl-2-((1E,3Z)-5-(1-butyl-1H-benzo(cd)indol-(2E)-ylidene)-3-(4,5-dimethoxy-cyclohexa-1,5-dienyl)-penta-1,3-dienyl)-benzo(cd)indole, 1-butyl-2-((1E,3Z)-5-(1-butyl-1H-benzo(cd)indol-(2E)-ylidene)-3-(4-fluoro-phenyl)-penta-1,3-dienyl)-benzo(cd)indole, 1-butyl-2-((1E,3Z)-5-(1-butyl-1H-benzo(cd)indol-(2E)-ylidene)-3-(3-fluoro-phenyl)-penta-1,3-dienyl)-benzo(cd)indole, and 1-butyl-2-((1E,3Z)-5-(1-butyl-1H-benzo(cd)indol-(2E)-ylidene)-3-(4-methoxy-phenyl)-penta-1,3-dienyl)-benzo(cd)indole are disclosed.    EXAMPLE - Dimethylformamide (0.12 mol) and phenylacetic acid chloride (0.08 mol) were heated at 70 degrees C, and phosphorus oxychloride (0.24 mol) was added. The obtained mixture was stirred at 70 degrees C for 3 hours, cooled to room temperature, and potassium carbonate was added until pH was set to 10. Toluene (70.1 g) was added to the obtained mixture, refluxed for 3 hours, and cooled to room temperature to obtain aldehyde intermediate. The obtained aldehyde intermediate (0.015 mol), sodium acetate (0.027), methanol (48.5 g), and acetic anhydride (0.12 mol) were reacted for 3 hours, and cooled to room temperature. The precipitate is filtered from the obtained mixture, recrystallized, washed and dried to obtain cyanine-type compound (I).