porphyrins


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Related to porphyrins: porphyria, Apolipoproteins

por·phy·rins

(pōr'fi-rinz),
Pigments widely distributed throughout nature (for example, heme, bile pigments, cytochromes) consisting of four pyrroles joined in a ring (porphin) structure. They are substitution products of porphin (porphyrin) and comprise several varieties, differing for the most part in the side chains (for example, methyl, ethyl, vinyl, formyl, carboxyethyl, carboxymethyl) present at the eight available positions on the pyrrole rings. Depending on the nature of the side chains, the prefixes deutero-, etio-, meso-, proto-, etc., are attached to porphyrins. Distribution within each class is by types I, II, III, or IV. Porphyrins combine with various metals (for example, iron, copper, magnesium) to form metalloporphyrins, and with nitrogenous substances.

por·phy·rins

(pōr'fir-inz)
Pigments widely distributed throughout nature (e.g., heme, bile pigments, cytochromes) consisting of four pyrroles joined in a ring (porphin) structure.
References in periodicals archive ?
Manganese(III) tetrakis(1-methyl-4-pyridyl) porphyrin, a superoxide dismutase mimetic, reduces disease severity in in vitro and in vivo models for dry-eye disease.
The optical and catalytic properties are based on one hand on porphyrin redox versatility and on the other hand on the redox chemistry of Co(II) that can be converted into a more nucleophilic Co(I) species by single-electron reduction process [19].
As depicted in Figure 2A, the benzoate arms of quadrangular porphyrin ligand TCPP were fully deprotonated to coordinate to four Y ions, making TCPP to serve as a tetra-dentate linker.
indicated that dicationic porphyrins having two cations in adjacent meso-phenyl had a highly polarized charge distribution increasing its amphiphilicity property [47].
Encouraged by the multitude of analytical applications of manganese porphyrins for the detection of active biological molecules, we investigated a metallated porphyrin, chloro[5,10,15,20-tetrakis-(4-methylphenyl) porphyrinato manganese(III)], both alone and in complex with gold colloid for the detection of [beta]-carotene.
Guillen et al., "Optical detection of amine vapors using ZnTriad porphyrin thin films," Sensors and Actuators B: Chemical, vol.
"First-principles quantum chemical studies of porphyrins." Acc.
In the past, porphyria testing was performed using the Watson-Schwartz test, which used Ehrlich's reagent to precipitate porphyrins in a urine sample, (4) and was used as a "bedside" test.
Metalloporphyrin are compounds formed by a combination of porphyrin and metal ions, playing important roles in catalysis, fluorescence, sensing, optical imaging, electronics, photochemistry, and biological applications [1-6].
This cationic porphyrin contains a large [pi]-planar structure and cationic functional groups providing strong [pi]-[pi] stacking and electrostatic interactions with G-quartets and phosphate groups on the G4 DNA.
After admission, we performed a urine porphyrin test based on his acute porphyria-like symptoms.
Clinical manifestations are predominantly visceral or cutaneous, depending on the affected enzyme and what step of the pathway is compromised, resulting in both the accumulation of some certain porphyrins and the deficit of others.