TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The semiconductor layer comprises a semiconductor material containing titanium oxide or zinc oxide.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation: No general preparation given. Preferred Definitions:    X=carboxy, hydroxy, sulfonic acid group, or phosphonic acid group;and    organic group containing electron-donating substituent=aryl containing electron-donating substituent.    SPECIFIC COMPOUNDS - 192 Compounds (I) are disclosed e.g. 2-(3-cyano-2-(dicyanomethylidene)-4-(1-octyl-1H-indol-3-yl)-5-oxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid of formula (IA), 2-(3-cyano-4-(4-(dibutylamino)phenyl)-2-(dicyanomethylidene)-5-oxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid, 2-(3-cyano-2-(dicyanomethylidene)-4-(4-(dodecyl(methyl)amino)phenyl)-5-oxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid, 2-(3-(4-(bis(2-cyanoethyl)amino)phenyl)-4-cyano-5-(dicyanomethylidene)-2-oxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid, and 2-(3-cyano-2-(dicyanomethylidene)-4-(4-(diethylamino)phenyl)-5-oxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid.    EXAMPLE - (In g) 4-cyano-5-dicyanomethylene-3-hydroxy-2-oxo-3-pyrroline disodium salt (7.5) and N,N-dibutylaniline (8.25) were dissolved in N,N-dimethylformamide (75 ml). Phosphorus oxychloride (15) was dripped and stirred at room temperature. The reaction mixture was poured into ice water (100 ml) and the precipitated crystal was filter-separated and washed with warm water several times. 2-(3-Cyano-4-(4-(dibutylamino)phenyl)-5-oxo-2,5-dihydro-1H-pyrrol-2-ylidene)propanedinitrile (7.06) was obtained by heat-stirring the product in ethanol/acetonitrile and washing, with a yield of 60%. t-Butyl bromoacetate (4.9) and the obtained compound were dissolved in acetonitrile (200 ml). Potassium carbonate (2.29) was added and stirred at 80 degrees C for 3.5 hours, and the mixture was poured into ice water after cooling. The precipitated crystal was filter-separated, heat-stir washed using ethanol (150), to obtain tert-butyl 2-(3-cyano-4-(4-(dibutylamino)phenyl)-2-(dicyanomethylidene)-5-oxo-2,5-dihydro-1H-pyrrol-1-yl)acetate (5.5) with a yield of 68%. The obtained compound (4.5) and p-toluenesulfonic acid monohydrate (2.1) were dissolved in acetonitrile (100 ml), and heat-refluxed for 6 hours. The mixture was poured into ice water (1000 ml) after cooling. The precipitated crystal was filtered and washed with water. The crystal was dissolved in acetone and reprecipitated to obtain 2-(3-cyano-2-(dicyanomethylidene)-4-(1-octyl-1H-indol-3-yl)-5-oxo-2,5-dihydro-1H-pyrrol-1-yl)acetic acid (3) with a yield of 75%. The ( lambda )max of the compound with respect to acetonitrile was 646 nm. The compound provided photoelectric conversion elements having a photoelectric conversion efficiency of 4.3%.