- Hydrating the Bispropionate Notch in Malaria Pigment: A New Structural Motif in the Iron(III)(deuteroporphyrin) Dimer
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Treating deuterohemin, chloro(deuteroporphyrinato)iron(III), with a non-coordinating base in DMSO/methanol allows for the isolation of [(deuteroporphyrinato)iron(III)]2, deuterohematin anhydride (DHA), an analogue of malaria pigment, the natural product of heme detoxification by malaria. The structure of DHA obtained from this solvent system has been solved by X-ray powder diffraction analysis and displays many similarities, yet important structural differences, to malaria pigment. Most notably, a water molecule of solvation occupies a notch created by the propionate side chains and stabilizes a markedly bent propionate ligand coordinated with a long Fe?O bond, and a carboxylate cluster associated with water molecules is generated. Together, these features account for its increased solubility and more open structure, with an increased porphyrin–porphyrin separation. The IR spectroscopic signature associated with this structure also accounts for the strong IR band at 1587 cm?1 seen for many amorphous preparations of synthetic malaria pigment, and it is proposed that stabilizing these structures may be a new objective for antimalarial drugs. The important role of the vinyl substituents in this biochemistry is further demonstrated by the structure of deuterohemin obtained by single-crystal X-ray diffraction analysis.
- Kuter, David,Suárez, Liliana,Dodd, Erin L.,Noll, Bruce C.,Stephens, Peter W.,Bohle, D. Scott
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- Synthesis and structure of five or six-coordinate manganese deuteroporphyrin-niacin dyads with intramolecular axial pyridine
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Deuteroporphyrin-niacin dyads with different chain lengths have been synthesized by modification of the propionate side chains of hemin. When a manganese ion was inserted into the porphyrin core, the UV spectral shift of manganese deuteroporphyrin-niacin dyads were experimentally demonstrated to mainly originate from the intramolecular coordination. In order to elaborate the intramolecular coordination, the spectra of single manganese porphyrin complexes in CH2Cl2 solution were measured and compared to that of the addition of axial ligands (pyridine and methyl nicotinate). Among all the synthetic dyads, the compounds of 2,7,12,18-tetramethyl-13,17-di(3- hydroxypropyl nicotinate) porphyrin and 2,7,12,18-tetramethyl-13,17-di(3- aminoethyl nicotinate) porphyrin manganese bearing the short chains did not show intramolecular coordination of the terminal base on the metal ion. Other three compounds of the niacin moiety indirectly bonded to the propionate side chains of manganese porphyrin through the diols linkage exhibited optical spectra characteristic of five or six-coordinate manganese complexes. These results indicate that the niacin groups' access to the Mn(III) center depended on the chain lengths.
- Sun, Chengguo,Hu, Bingcheng,Zhao, Donghui,Liu, Zuliang
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p. 130 - 137,8
(2020/08/20)
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- PORPHYRIN LINKED METRONIDAZOLE AGAINST GUM DISEASE: PORPHYROMONAS GINGIVALIS
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The present invention relates generally to targeted molecular agents (TMAs) directed to a particular organism or group of organisms and uses thereof. More particularly, the present invention provides TMAs having a targeting moiety which comprises a natural or induced auxotrophic requirement of the particular organism as a vehicle for directing an agent linked to the moiety to be delivered to the target organism. The TMAs of the present invention are useful for targeting molecules such as antimicrobial agents and diagnostic agents to selected organisms.
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Page/Page column 29; 57
(2008/06/13)
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- SYNTHESIS OF CHLORINS FROM UNSYMMETRICALLY SUBSTITUTED IRON PORPHYRINS
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Mesohemin (1), deuterohemin (2), protohemin (3), 6,7-dipropylmesohemin (22), 1-(2-carboxyethyl)-meso-tetraphenylhemin (30), coprohemin-II (23), 2-acetyldeuterohemin (40), 2,4-diacetyl-deuterohemin (41), and phyllohemin (51) were reduced to chlorins using
- Burns, Dennis H.,Lai, Jan-Ji,Smith, Kevin M.
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p. 3119 - 3132
(2007/10/02)
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- Reactions of Iron Porphyrins with Methyl Radicals
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The reactions of methyl radicals with ferric, ferrous, and iron-free deuteroporphyrin have been investigated in neutral and alkaline water-2-propanol mixtures.Steady-state radiolysis of methyl chloride saturated solutions of ferric deuteroporphyrin, or ch
- Brault, D.,Neta, P.
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p. 2705 - 2710
(2007/10/02)
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- Evidence for a Fast (Major) and Slow (Minor) Pathway in the Schumm Devinylation Reaction of Vinyl Porphyrins
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The devinylation of protohemin in molten resorcinol is shown to proceed by two pathways.Two of the three possible intermediates in the minor (slow) pathway have been isolated and characterized as their dimethyl esters.In both, C-alkylation of resorcinol at the porphyrin C-1' vinyl side chains has occured.These intermediates are, however, converted into deuterohemin far too slowly for them to be on the major pathway from protohemin to deuterohemin.It is suggested that other intermediates, possibly in which O-alkylation of resorcinol has occurred, are intermediates in the major (fast) pathway from protohemin to deuterohemin.
- DiNello, Robert K.,Dolphin, David H.
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p. 3498 - 3502
(2007/10/02)
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