Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Novel bay-functionalized perylene diimides with additional substitution sites close to the perylene core have been prepared by the reaction between 1,7(6)-dibromoperylene diimide 6 (dibromo-PDI) and 2-(benzyloxymethyl)pyrrolidine 5. Distinct differences in the chemical behaviors of the 1,7- and 1,6-regioisomers have been discerned. While the 1,6-dibromo-PDI produced the corresponding 1,6-bis-substituted derivative more efficiently, the 1,7-dibromo-PDI underwent predominant mono-debromination, yielding a mono-substituted PDI along with a small amount of the corresponding 1,7-bis-substituted compound. By varying the reaction conditions, a controlled stepwise bis-substitution of the bromo substituents was also achieved, allowing the direct synthesis of asymmetrical 1,6- and 1,7-PDIs. The compounds were isolated as individual regioisomers. Fullerene (C60) was then covalently linked at the bay region of the newly prepared PDIs. In this way, two separate sets of perylene diimide-fullerene dyads, namely single-bridged (SB-1,7-PDI-C60 and SB-1,6-PDI-C60) and double-bridged (DB-1,7-PDI-C60 and DB-1,6-PDI-C60), were synthesized. The fullerene was intentionally attached at the bay region of the PDI to achieve close proximity of the two chromophores and to ensure an efficient photoinduced electron transfer. A detailed study of the photodynamics has revealed that photoinduced electron transfer from the perylene diimide chromophore to the fullerene occurs in all four dyads in polar benzonitrile, and also occurs in the single-bridged dyads in nonpolar toluene. The process was found to be substantially faster and more efficient in the dyads containing the 1,7-regioisomer, both for the singly- and double-bridged molecules. In the case of the single-bridged dyads, SB-1,7-PDI-C60 and SB-1,6-PDI-C60, different relaxation pathways of their charge-separated states have been discovered. To the best of our knowledge, this is the first observation of photoinduced electron transfer in PDI-C60 dyads in a nonpolar medium.
 ...
PMID:Direct evidence of significantly different chemical behavior and excited-state dynamics of 1,7- and 1,6-regioisomers of pyrrolidinyl-substituted perylene diimide. 2352 50

In this work, the electrophoretic behavior of hydrophobic fullerenes [buckminsterfullerene (C60), C70, and N-methyl-fulleropyrrolidine (C60-pyrr)] and water-soluble fullerenes [fullerol (C60(OH)24); polyhydroxy small gap fullerene, hydrated (C120(OH)30); C60 pyrrolidine tris acid (C60-pyrr tris acid); and (1,2-methanofullerene C60)-61-carboxylic acid (C60CHCOOH)] in micellar electrokinetic capillary chromatography (MECC) was evaluated. The aggregation behavior of the water-soluble compounds in MECC at different buffer and sodium dodecyl sulfate (SDS) concentrations and pH values of the background electrolyte (BGE) was studied by monitoring the changes observed in the electrophoretic pattern of the peaks. Broad and distorted peaks that can be attributed to fullerene aggregation were obtained in MECC which became narrower and more symmetric by working at low buffer and SDS concentrations (below the critical micelle concentration, capillary zone electrophoresis (CZE) conditions). For the characterization of the suspected aggregates formed (size and shape), asymmetrical flow field-flow fractionation (AF4) and transmission electron microscopy (TEM) were used. The results showed that the increase in the buffer concentration promoted the aggregation of the particles, while the presence of SDS micelles revealed multiple peaks corresponding to particles of different aggregation degrees. Furthermore, MECC has been applied for the first time for the analysis of C60 in two different cosmetic products (i.e., anti-aging serum and facial mask).
...
PMID:Aggregation behavior of fullerenes in aqueous solutions: a capillary electrophoresis and asymmetric flow field-flow fractionation study. 2631 84