Synthesis and physical performance of indole and benzimidazole cyanine dyes

Abstract

Nine indole and benzimidazole cyanine dyes, used as green-sensitizing dyes in photographic emulsions, are synthesized. The compounds are characterized from mass spectrometric and NMR spectroscopic data, and elemental analysis. FAB mass spectrometry proved to be an efficient method for determining the structure of the compounds. From UV-VIS data of the compounds the sensitizing properties of the cyanine dyes are predicted. The reflection spectrum of Gs2-9 coated in photographic emulsions showed J-aggregation behaviour at A = 560 nm. Unsymmetric benzimidazole-indole cyanine dyes showed good to excellent green sensitizing properties in photographic emulsions, whereas symmetric indole cyanine dyes showed heavy residual colour and no sensitizing properties.

In vitro fermentability and antioxidant capacity of the indigestible fraction of cooked black beans (Phaseolus vulgaris L.), lentils (Lens culinaris L.) and chickpeas (Cicer arietinum L.)

“…We studied the effect of varying the anion on the charge and discharge cycles of the battery. Figure shows the chemical structures of the parent cyanine dye 1 ,7 and dendronised versions 2 (with an iodide anion), and 3 (with a hexafluorophosphate anion). The first generation dendrimer with the iodide anion, 2 , was prepared in two steps from 5‐bromo‐1,2,3,3‐tetramethyl‐3 H ‐indolium iodide 4 8 ( Scheme ).…”

Interactions of AsCy3 with Cysteine-Rich Peptides

“…These values compare well with those in methanol, where an absorbance maximum at 549 nm (ε 549 = 120,000 M –1 cm –1 ) was reported. 19 Both the absorbance and emission maxima of AsCy3 are red-shifted relative to Cy3; under identical conditions AsCy3 exhibited maximal absorbance at 564 nm (ε 564 = 103,000 M –1 cm –1 ) and maximal emission at 575 nm ( Figure S1 in Supporting Information ). These values differ slightly from those reported: λ max = 560 nm (absorbance, ε 560 = 180,000 M –1 cm –1 ); λ max = 568 nm (emission).…”

Photo‐Rechargeable Battery Effect in First Generation Cationic‐Cyanine Dendrimers

“…Figure 1 shows the chemical structures of the parent cyanine dye 1 , [ 7 ] and dendronised versions 2 (with an iodide anion), and 3 (with a hexafl uorophosphate anion). The fi rst generation dendrimer with the iodide anion, 2 , was prepared in two steps from 5-bromo-1,2,3,3-tetramethyl-3 H -indolium iodide 4 [ 8 ] ( Scheme 1 ).…”