Color primary pathways

Macrocycle 8.5b is formally a non-aromatic system that contains 40 n-elec-trons in its primary conjugation pathway. In spite of this, the molecule is brightly colored and displays a strong absorbance band in the visible spectrum at 642 nm (g = 312 500 M cm in CH2CI2) (Figure 8.1.1). In fact, the beautiful turquoise color displayed by organic solutions of 8.5 led the original authors to name this class of expanded porphyrins turcasarins . 

The presence of phenoloxidase in all phyla of living organisms demonstrates that their origin is very early in the history of life. It is involved in the biosynthesis of melanins and other polyphenolic compounds. Depending on the species, phenoloxidases are involved in the primary immune response, wound healing, sclerotization, and coloring processes. In mammals, L-tyrosine is the initial substrate in the pathway leading to the final products of black-brown eumelanins, red-yellow pheomelanins, or a mixture of pheo-and eumelanins.Ti ... 

Plant cells produce far more chemical compounds than is necessary for their basic functions i.e., biochemical pathways for survival and propagation. Basic or primary metabolism refers to all biochemical processes for the normal anabolic and catabolic pathways, which result in assimilation, respiration, transport, and differentiation. Basic or primary metabolism is shared by all cells, while secondary metabolism generates diverse and seemingly less essential or nonessential byproducts called secondary products. The secondary products are the colors, flavors, and smells, which are the sources of fine chemicals such as drugs, insecticides, dyes, flavors, and fragrances, and plant-growth regulators found in medicinal plants. 

Essaka, D. C. Prendergast, J. Keithley, R. B. Palcic, M. M. Hindsgaul, O. Schnaar, R. L. Dovichi, N. J. Metabolic cytometry Capillary electrophoresis with two-color fluorescence detection for the simultaneous study of two glycosphingolipid metabolic pathways in single primary neurons. Anal. Chem. 2012, 84, 2799-2804. 

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