Search results for "Porphin"
showing 10 items of 31 documents
Vasodilator Effects of Liriodenine and Norushinsunine, Two Aporphine Alkaloids Isolated from <i>Annona cherimolia,</i>in Rat Aorta
1995
The effect of two aporphines, liriodenine and norushinsunine, isolated from Annona cherimolia, were studied in the rat aorta in order to examine their mechanism of action. Both alkaloids (10–7–10–4 mol/l) showed relaxant effects on the contractions elicited by 10–6 mol/l noradrenaline (NA) or 80 mmol/l KC1, but, while liriodenine showed a nonspecific relaxant action on both spasmogens, norushinsunine was more potent on KC1-induced contraction. In Ca2+-free medium, both alkaloids (0.1 mmol/l) inhibited the responses elicited by NA, but not those elicited by caffeine. This inhibitory action occurred when the alkaloids were present during the release of the Ca2+ internal stores or during the r…
8-NH2-Boldine, an Antagonist of α1Aand α1BAdrenoceptors without Affinity for the α1DSubtype: Structural Requirements for Aporphines at α1-Adrenocepto…
2005
Structure-activity analysis of 21 aporphine derivatives was performed by examining their affinities for cloned human alpha (1A), alpha (1B) and alpha (1D) adrenoceptors (AR) using membranes prepared from rat-1 fibroblasts stably expressing each alpha (1)-AR subtype. All the compounds tested competed for [ (125)I]-HEAT binding with steep and monophasic curves. The most interesting compound was 8-NH (2)-boldine, which retains the selective affinity for alpha(1A)-AR (pKi = 6.37 +/- 0.21) vs. alpha(1B)-AR (pKi = 5.53 +/- 0.11) exhibited by 1,2,9,10-tetraoxygenated aporphines, but shows low affinity for alpha(1D)-AR (pKi < 2.5). Binding studies on native adrenoceptors present in rat cerebral cor…
Porphyrin tributyltin(IV) complexes for a novel approach in the tratment of human melanoma
2012
Melanoma is the most deadly form of skin cancer, largely refractory to existing therapies. The study of porphyrin derivatives as potential anti-tumor drugs has been an interesting field of investigation in the last years. Recently, a photo-independent cytotoxic effect of (Bu3Sn)4TPPS in the blocking melanoma cell proliferation an inducing a morphology cell change was investigated.[1] Amphiphilic CD (ACyD) provides more water soluble and adaptable nanovectors through modulation of the balance between hydrophobic and hydrophilic chains at both CD sides. ACyD can be conveniently tailored by covalently appending fluorescent label or receptor-targeting glycosyl- groups and can encapsulate conven…
"Dna binding of organotin(IV) complexes of meso-tetra (4 sulfonatophenyl) porphine showing cellular activity"
2016
Our research group has reported about the synthesis of alkynyl-substituted metallophthalocyanines of symmetric and unsymmetric nature. In this study, a novel phthalocyanine precursor bearing pyridin-3-ylethynyl groups and its tetrasubstituted metallo- phthalocyanines at peripheral positions were reported.
(Bu3Sn)4TPPS and (Bu2Sn)2TPPS significantly inhibit the growth, migrationand tumorigenicity of human malignant melanoma cells
2018
Melanoma is one of the most aggressive and treatment-resistant human cancers, it is responsible worldwide for the 80% of skin cancer related deaths which is largely due to its propensity to metastasize to other organs. The growing understanding of the pathways involved in melanoma progression and development has led to the identification of some interesting new molecules, however, the treatment options for metastatic melanoma remain limited. Indeed, the key step in metastasis development is the tumour cell invasion of the nearby host tissue and the journey powerfully depends on the detachment of single tumour cells from the primary tumour. Therefore, the ability to block the migratory and i…
CCDC 1872265: Experimental Crystal Structure Determination
2020
Related Article: Marta Viciano-Chumillas, Geneviève Blondin, Martin Clémancey, Jurek Krzystek, Mykhaylo Ozerov, Donatella Armentano, Alexander Schnegg, Thomas Lohmiller, Joshua Telser, Francesc Lloret, Joan Cano|2020|Chem.-Eur.J.|26|14242|doi:10.1002/chem.202003052
3,4-Dihydroxy- and 3,4-methylenedioxy- phenanthrene-type alkaloids with high selectivity for D2 dopamine receptor.
2013
Abstract Dopamine-mediated neurotransmission plays an important role in relevant psychiatric and neurological disorders. Nowadays, there is an enormous interest in the development of new drugs acting at the dopamine receptors (DR) as potential new targets for the treatment of schizophrenia or Parkinson’s disease. Previous studies have revealed that isoquinoline compounds such as tetrahydroisoquinolines (THIQs) can behave as selective D 2 dopaminergic alkaloids. In the present study we have synthesized five aporphine compounds and five phenanthrene alkaloids and evaluated their potential dopaminergic activity. Binding studies on rat striatal membranes were used to evaluate their affinity and…
Theoretical Studies of the Electronic Spectra of Organic Molecules
1995
The complete active space (CAS) SCF method in conjunction with multiconfigurational second-order perturbation theory (CASPT2) has been used to study the electronic spectra of a large number of molecules. The wave functions and the transition properties are computed at the CASSCF level, while dynamic correlation contributions to the excitation energies are obtained through the perturbation treatment. The methods yield energies, which are accurate to at least 0.2 eV, except in a few cases, where the CASSCF reference function does not characterize the electronic state with sufficient accuracy. The applications comprise: the polyenes from ethene to octatetraene (cis- and trans-forms); a number …
Interpretation of the electronic absorption spectrum of free base porphin by using multiconfigurational second-order perturbation theory
1998
Abstract Multiconfigurational second-order perturbation (CASPT2) calculations have been performed on the low-lying optically allowed valence excited states of the free base porphin molecule in order to assign the four lowest bands of the spectrum. The low-lying triplet states have also been characterized. A basis set of the atomic natural orbital type of split-valence plus polarization quality for first-row atoms has been employed. Polarization functions are important for an accurate description of the transitions. These CASPT2 results provide a consistent picture of the experimental spectrum. Each band of the spectrum up to 4.5 eV is composed of a pair of states, which become degenerate in…
Electrocatalytic properties of manganese and cobalt polyporphine films toward oxygen reduction reaction
2018
International audience; Novel member of polymetalloporphines, namely manganese polymetalloporphine of type I (pMnP-I) obtained by ion exchange from magnesium polyporphine of type I (pMgP-I) is reported for the first time and compared to its cobalt analogue (pCoP-I). Both polymer films have been obtained via two-step procedure: demetaladon of the pMgP-I electrode film via its exposure to trifluoroacetic acid solution, resulting in formation of the metal-free polyporphine of type I (pH(2)P-I) followed by electrochemically induced incorporation of Co or Mn ions from the acetonitrile solution of cobalt and manganese perchlorates. A further oxidative transformation of pCoP-I, polymer films has l…