Results 131 to 140 of about 11,005 (181)
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Insertion of cobalt into tetrapyrroles
2022Vitamin B12 is one of the most complex cofactors known, and this chapter will discuss current understanding with regards to the cobalt insertion step of its syntheses. Two total syntheses of vitamin B12 were reported in the 1970s, which remain two of the most exceptional achievements of natural product synthesis.
J A, Morris, B S, Lickey, M D, Liptak
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Metamorphosis of Tetrapyrrole Macrocycles
ChemInform, 2006AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Mathias O, Senge, Natalia N, Sergeeva
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Tetrapyrrole Biosynthesis in Higher Plants
Annual Review of Plant Biology, 2007Tetrapyrroles play vital roles in various biological processes, including photosynthesis and respiration. Higher plants contain four classes of tetrapyrroles, namely, chlorophyll, heme, siroheme, and phytochromobilin. All of the tetrapyrroles are derived from a common biosynthetic pathway. Here we review recent progress in the research of tetrapyrrole
Ryouichi, Tanaka, Ayumi, Tanaka
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A reaction of the superoxide radical with tetrapyrroles
Archives of Biochemistry and Biophysics, 1982Bilirubin and biliverdin were bleached during exposure to the aerobic xanthine oxidase reaction. Enzymic scavenging of O2−, by Superoxide dismutase, inhibited, whereas enzymic scavenging of H2O2, by catalase, did not. Increasing the rate of production of O2− without increasing the turnover rate of xanthine oxidase, by increasing pO2, accelerated the ...
P, Robertson, I, Fridovich
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Naturally Occurring Cyclic Tetrapyrroles
2002Of the porphyrinoid structures occurring in nature the most important and most widespread are the red blood pigment heme (1), the green pigment of plant photosynthesis chlorophyll a (2), the bacterial photo-synthetic pigment bacteriochlorophyll a (3), and the “antipernicious” red pigment vitamin B12 (4).
F P, Montforts, M, Glasenapp-Breiling
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Chiral Sensing by Nonchiral Tetrapyrroles
Accounts of Chemical Research, 2015Enantiomeric excess (ee) is a measure of the purity of an enantiomer of a chiral compound with respect to the presence of the complementary enantiomer. It is an important aspect of chemistry, especially in the fields of pharmaceuticals and asymmetric catalysis. Existing methods for determination of enantiomeric excesses using nuclear magnetic resonance
Jan, Labuta +4 more
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Glycoconjugated tetrapyrrolic macrocycles
Journal of the American Chemical Society, 1989Preparation de porphyrine ou de phtalocyanine metalliques substituees par le glucose a partir de la condensation du tetraacetyl β-D-glucose-2 benzaldehyde avec le ...
Philippe Maillard +3 more
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2003
This chapter addresses basic methodology that can be used to obtain tetrapyrrole macrocycles in the porphyrin and chlorin series from natural materials and some simple methods for the total chemical synthesis of typical pyrroles and porphyrins. The aim is to provide investigators with enough information to decide whether to take on the task of ...
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This chapter addresses basic methodology that can be used to obtain tetrapyrrole macrocycles in the porphyrin and chlorin series from natural materials and some simple methods for the total chemical synthesis of typical pyrroles and porphyrins. The aim is to provide investigators with enough information to decide whether to take on the task of ...
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(Invited) Charge Separation in Tetrapyrrole-Graphene and Tetrapyrrole-Slgo-Fullerene Hybrids
ECS Meeting Abstracts, 2013Abstract not Available.
F. D'Souza +4 more
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Atropisomerism in linear tetrapyrroles
Tetrahedron, 2002Abstract Novel bilirubin and biliverdin congeners with propionic acids replaced by o -carboxyphenyl exhibit diastereomerism due to axial chirality about the carbon–carbon single bond linking the o -carboxyphenyl group to a pyrrole ring. Evidence for atropisomerism was found even in the monopyrrole precursor, ethyl 3,5-dimethyl-4-( o -carboxyphenyl ...
Stefan E Boiadjiev, David A Lightner
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