3151-55-1Relevant academic research and scientific papers
Chlorin photosensitizers sterically designed to prevent self-aggregation
Uchoa, Adjaci F.,De Oliveira, Kleber T.,Baptista, Mauricio S.,Bortoluzzi, Adailton J.,Iamamoto, Yassuko,Serra, Osvaldo A.
, p. 8824 - 8832 (2011)
The synthesis and photophysical evaluation of new chlorin derivatives are described. The Diels-Alder reaction between protoporphyrin IX dimethyl ester and substituted maleimides furnishes endo-adducts that completely prevent the self-aggregation of the chlorins. Fluorescence, resonant light scattering (RLS) and 1H NMR experiments, as well as X-ray crystallographic have demonstrated that the configurational arrangement of the synthesized chlorins prevent π-stacking interactions between macrocycles, thus indicating that it is a nonaggregating photosensitizer with high singlet oxygen (ΦΔ) and fluorescence (Φf) quantum yields. Our results show that this type of synthetic strategy may provide the lead to a new generation of PDT photosensitizers.
A deep, water-soluble cavitand acts as a phase-transfer catalyst for hydrophobic species
Hooley, Richard J.,Biros, Shannon M.,Rebek Jr., Julius
, p. 3517 - 3519 (2007/10/03)
Overcoming inhibition: A deep, water-soluble cavitand has been shown to extract various N-substituted maleimides into aqueous solution through the hydrophobic effect. These complexes react with a water-soluble thiol to confer water solubility to the produ
MYCOBACTERIAL INHIBITORS
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Page/Page column 8, (2010/11/08)
The invention provides the use of certain succinimide compounds in the treatment of mycobacterial diseases.
Design, synthesis, and biochemical evaluation of N-substituted maleimides as inhibitors of prostaglandin endoperoxide synthases
Kalgutkar, Amit S.,Crews, Brenda C.,Marnett, Lawrence J.
, p. 1692 - 1703 (2007/10/03)
N-(Carboxyalkyl)maleimides are rapid as well as time-dependent inhibitors of prostaglandin endoperoxide synthase (PGHS). The corresponding N- alkylmaleimides were only time-dependent inactivators of PGHS, suggesting that the carboxylate is critical for rapid inhibition. Several N-substituted maleimide analogs containing structural features similar to those of the nonsteroidal anti-inflammatory drug aspirin were synthesized and evaluated as inhibitors of PGHS. Most of the aspirin-like maleimides inactivated the cyclooxygenase activity of purified ovine PGHS-1 in a time- and concentration-dependent manner similar to that of aspirin. The peroxidase activity of PGHS was also inactivated by the maleimide analogs. The cyclooxygenase activity of the inducible isozyme, i.e., PGHS-2, was also inhibited by these compounds. The corresponding succinimide analog of N-5- maleimido-2-acetoxy-1-benzoic acid did not inhibit either enzyme activity, suggesting that inactivation was due to covalent modification of the protein. The mechanism of inhibition of PGHS-1 by N-(carboxyheptyl)maleimide was investigated. Incubation of apoPGHS-1 with 2 equiv of N-(carboxyheptyl)[3,4- 14C]maleimide led to the incorporation of radioactivity in the protein, but no adduct was detected by reversed-phase HPLC, suggesting that it was unstable to the chromatographic conditions. Furthermore, hematin- reconstituted PGHS-1, which was rapidly inhibited by N- (carboxyheptyl)maleimide, displayed spontaneous regeneration of about 50% of the cyclooxygenase and peroxidase activities, suggesting that the adduct responsible for the inhibition breaks down to regenerate active enzyme. ApoPGHS-1, inhibited by N-(carboxyheptyl)maleimide, did not display regeneration of enzyme activity, but addition of hematin to the inhibited apoenzyme led to spontaneous recovery of about 50% of cyclooxygenase activity. These results suggest that addition of heme leads to a conformational change in the protein which increases the susceptibility of the adduct toward hydrolytic cleavage. ApoPGHS-1, pretreated with N(carboxyheptyl)maleimide, was resistant to trypsin cleavage, suggesting that the carboxylate functionality of the maleimide binds in the cyclooxygenase channel. A model for the interaction of N-(carboxyheptyl)maleimide in the cyclooxygenase active site is proposed.
COMPOUNDS AND COMPOSITIONS FOR INHIBITION OF CYCLOOXYGENASE ACTIVITY
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, (2008/06/13)
The present invention includes N-substituted maleimides (1(H)-Pyrrole-2,5-dione (Maleimide) analogs and succinimides which act as potent nonsteroidal anti-inflammatory drugs and are capable of dual inactivation or selective inactivation of the cyclooxygenase and the peroxidase activities of prostaglandin endoperoxide synthase (PGHS).
