G. Seoane - Academia.edu (original) (raw)
Papers by G. Seoane
Fundamentals and Applications, 2012
Journal of Molecular Structure, 2010
The azine bridged dicatechol ligand (E,E)-benzaldehyde azine (H 4 L) was fully characterized by X... more The azine bridged dicatechol ligand (E,E)-benzaldehyde azine (H 4 L) was fully characterized by X-ray analysis. The reaction of [ReCl 6 ] 2À with this compound was studied and the novel Re(IV) complex (HNEt 3)(N-Bu 4)[ReCl 4 (H 2 L)] was prepared and characterized. The structure and spectroscopy of the compound H 4 L and its Re(IV) complex were studied experimentally and by means of density functional calculations.
Journal of Molecular Structure: THEOCHEM, 2002
A computer assisted molecular modeling was used to design molecules having a shape complementary ... more A computer assisted molecular modeling was used to design molecules having a shape complementary to the active site of glutathione reductase (GR) and trypanothione reductase (TR). The designed 5-nitro compound derivatives, were obtained from structural knowledge gleaned on glutathione (GSSG), trypanothione (T[S] 2) and GSP disul®de (glutathionylspermidine disul-®de). These molecules form complexes with the enzymes GR and TR. The theoretical lead compound was: N1-[1-(5-nitro-2furyl)methylidene]-N4-{4-[3-(2,2,2-tri¯uoroacetyl)hexahydro-1-1-pyrimidynil]butyl} semicarbazide (NPIPCO). A multidisciplinary team developed around the efforts to synthesize this lead. In this work we report on eight compounds that were synthesized in the pathway to NPIPCO: 4-(2-methoxyethyl)-1-, 4-butyl-1-, 4-hexyl-1-and 2-methoxphenyl-1-(5-nitrofurfurilidene) semicarbazides and the corresponding 5-nitrothiophenes. These substances are expected to act as pro-transition state analogues. Enzymologic studies proved that many of these compounds are inhibitors of TR. Furthermore, they showed inhibitory activity on Tripanosoma cruzi growth in vitro.
Molecules, 2000
It describes the synthesis of new 1,2,6-Thiadiazin 1,1-dioxide derivatives using condensation of ... more It describes the synthesis of new 1,2,6-Thiadiazin 1,1-dioxide derivatives using condensation of the Knoevenagel type. The products are evaluated in vitro as trypanocidal agents.
Free Radical Biology and Medicine, 2010
Folia Parasitologica, 2001
The cytotoxicity of 18 new 1,2,6-thiadiazin-3,5-dione 1,1-dioxides was evaluated. This group of p... more The cytotoxicity of 18 new 1,2,6-thiadiazin-3,5-dione 1,1-dioxides was evaluated. This group of products was previously assayed against epimastigotes of Trypanosoma cruzi and some of them showed a high antiprotozoal activity. Thereafter 13 compounds with a high anti-epimastigote activity and low cytotoxicity were selected to be assayed against amastigotes. Some of the products showed the same or even lower cytotoxicity than nifurtimox and benznidazole, but most of them were very toxic for macrophages at 100 µg/ml. Only one of the compounds had an anti-amastigote activity similar to that of reference drugs at 10 µg/ml, but unfortunately this disappeared at lower concentrations.
European Journal of Medicinal Chemistry, 2001
Several new 1,2,5-oxadiazole N-oxide derivatives and some deoxygenated analogues were synthesized... more Several new 1,2,5-oxadiazole N-oxide derivatives and some deoxygenated analogues were synthesized to be tested as potential selective hypoxic cell cytotoxins. Compounds prepared were designed in order to gain insight into the mechanism of action of this kind of cytotoxin. Compounds were tested in oxia and hypoxia and they proved to be non-selective. 3-Cyano-N 2-oxide-4phenyl-1,2,5-oxadiazole showed the best cytotoxic activity in oxia. The cytotoxicity observed for these derivatives could be explained in terms of the electronic characteristics of the 1,2,5-oxadiazole substituents. Electrochemical and ESR studies were performed on the more cytotoxic derivative.
Molecules, 2000
New analogues of 3-Formyl-4-phenyl-1,2,5-oxadiazole N-oxide (1) are prepared and evaluated as cyt... more New analogues of 3-Formyl-4-phenyl-1,2,5-oxadiazole N-oxide (1) are prepared and evaluated as cytotoxic selective agents in hypoxia.
Pharmazie, 1998
Synthesis and biological evaluation of new 1,2,5-oxadiazole N-oxide derivatives with potential cy... more Synthesis and biological evaluation of new 1,2,5-oxadiazole N-oxide derivatives with potential cytotoxic effects are described. From the series of compounds tested, compounds 2 and 6 proved to be very active, although non-selective.
Strain and Its Implications in Organic Chemistry, 1989
Vinylcyclopropanes, vinyloxiranes, and vinylaziridines were prepared by either a [2+3] protocol i... more Vinylcyclopropanes, vinyloxiranes, and vinylaziridines were prepared by either a [2+3] protocol involving the additions of the dienolate of ethyl 2-bromocrotonate to enones, aldehydes, and some imines, or by a [4+1] protocol that utilized the intramolecular cycloadditions of diazoketones or azides to 1,3-dienes. The resulting strained 3-membered rings provided, through their energy contents, the necessary driving force for the corresponding rearrangments to annulated cyclopentenes, dihydrofurans, and pyrrolines respectively. The applications of these processes are highlighted in the syntheses of natural products containing five-membered rings. Retigeranic acid, ipomeamarone, and pyrrolizidine diols are the targets of these applications. An approach to the taxane skeleton is also advanced and is based on the ease with which endo vinylcyclopropanes undergo the divinylcyclopropane Cope rearrangement.
Acta Crystallographica Section C Crystal Structure Communications, 1999
ABSTRACT The title compound, C11H16O6, has been synthesized and isolated as the major product of ... more ABSTRACT The title compound, C11H16O6, has been synthesized and isolated as the major product of the osmylation of (5S,6R)-5,6-diacetoxy-1-methyl-1,3-cyclohexadiene. The molecule crystallizes in the monoclinic space group P2(1). The hexene ring exhibits a puckered distorted half-chair conformation, with all the chiral centres (C3, C4, C5 and C6) in the S configuration. One intramolecular and two intermolecular hydrogen bonds stabilize the molecule by the formation of infinite chains along b.
Proceedings of the 14th Brazilian Meeting on Organic Synthesis Proceedings, 2013
Synlett, 1990
... Page 8. 440 Tomas Hudlicky, Gustavo Seoane, John D. Price, Kumar G. Gadamasctti (in part) SYN... more ... Page 8. 440 Tomas Hudlicky, Gustavo Seoane, John D. Price, Kumar G. Gadamasctti (in part) SYNLETT Acknowledgements. ... In addition, Robert P. Short, James O. Frazier, and Frank J. Koszyk are extended special thanks for their roles in the developmental work. ...
Spectroscopy Letters, 1998
... ELECTRON SPIN RESONANCE AND CYCLIC VOLTAMMETRY STUDIES OF NITROFURANE AND NITROTHIOPHENE ANAL... more ... ELECTRON SPIN RESONANCE AND CYCLIC VOLTAMMETRY STUDIES OF NITROFURANE AND NITROTHIOPHENE ANALOGUES OF NIFURTIMOX. C. Olea-Azar', ha Maria Atria', Rossana di Maiof, G. Seoane2 and Hugo Cerecetto2 ...
Fundamentals and Applications, 2012
Journal of Molecular Structure, 2010
The azine bridged dicatechol ligand (E,E)-benzaldehyde azine (H 4 L) was fully characterized by X... more The azine bridged dicatechol ligand (E,E)-benzaldehyde azine (H 4 L) was fully characterized by X-ray analysis. The reaction of [ReCl 6 ] 2À with this compound was studied and the novel Re(IV) complex (HNEt 3)(N-Bu 4)[ReCl 4 (H 2 L)] was prepared and characterized. The structure and spectroscopy of the compound H 4 L and its Re(IV) complex were studied experimentally and by means of density functional calculations.
Journal of Molecular Structure: THEOCHEM, 2002
A computer assisted molecular modeling was used to design molecules having a shape complementary ... more A computer assisted molecular modeling was used to design molecules having a shape complementary to the active site of glutathione reductase (GR) and trypanothione reductase (TR). The designed 5-nitro compound derivatives, were obtained from structural knowledge gleaned on glutathione (GSSG), trypanothione (T[S] 2) and GSP disul®de (glutathionylspermidine disul-®de). These molecules form complexes with the enzymes GR and TR. The theoretical lead compound was: N1-[1-(5-nitro-2furyl)methylidene]-N4-{4-[3-(2,2,2-tri¯uoroacetyl)hexahydro-1-1-pyrimidynil]butyl} semicarbazide (NPIPCO). A multidisciplinary team developed around the efforts to synthesize this lead. In this work we report on eight compounds that were synthesized in the pathway to NPIPCO: 4-(2-methoxyethyl)-1-, 4-butyl-1-, 4-hexyl-1-and 2-methoxphenyl-1-(5-nitrofurfurilidene) semicarbazides and the corresponding 5-nitrothiophenes. These substances are expected to act as pro-transition state analogues. Enzymologic studies proved that many of these compounds are inhibitors of TR. Furthermore, they showed inhibitory activity on Tripanosoma cruzi growth in vitro.
Molecules, 2000
It describes the synthesis of new 1,2,6-Thiadiazin 1,1-dioxide derivatives using condensation of ... more It describes the synthesis of new 1,2,6-Thiadiazin 1,1-dioxide derivatives using condensation of the Knoevenagel type. The products are evaluated in vitro as trypanocidal agents.
Free Radical Biology and Medicine, 2010
Folia Parasitologica, 2001
The cytotoxicity of 18 new 1,2,6-thiadiazin-3,5-dione 1,1-dioxides was evaluated. This group of p... more The cytotoxicity of 18 new 1,2,6-thiadiazin-3,5-dione 1,1-dioxides was evaluated. This group of products was previously assayed against epimastigotes of Trypanosoma cruzi and some of them showed a high antiprotozoal activity. Thereafter 13 compounds with a high anti-epimastigote activity and low cytotoxicity were selected to be assayed against amastigotes. Some of the products showed the same or even lower cytotoxicity than nifurtimox and benznidazole, but most of them were very toxic for macrophages at 100 µg/ml. Only one of the compounds had an anti-amastigote activity similar to that of reference drugs at 10 µg/ml, but unfortunately this disappeared at lower concentrations.
European Journal of Medicinal Chemistry, 2001
Several new 1,2,5-oxadiazole N-oxide derivatives and some deoxygenated analogues were synthesized... more Several new 1,2,5-oxadiazole N-oxide derivatives and some deoxygenated analogues were synthesized to be tested as potential selective hypoxic cell cytotoxins. Compounds prepared were designed in order to gain insight into the mechanism of action of this kind of cytotoxin. Compounds were tested in oxia and hypoxia and they proved to be non-selective. 3-Cyano-N 2-oxide-4phenyl-1,2,5-oxadiazole showed the best cytotoxic activity in oxia. The cytotoxicity observed for these derivatives could be explained in terms of the electronic characteristics of the 1,2,5-oxadiazole substituents. Electrochemical and ESR studies were performed on the more cytotoxic derivative.
Molecules, 2000
New analogues of 3-Formyl-4-phenyl-1,2,5-oxadiazole N-oxide (1) are prepared and evaluated as cyt... more New analogues of 3-Formyl-4-phenyl-1,2,5-oxadiazole N-oxide (1) are prepared and evaluated as cytotoxic selective agents in hypoxia.
Pharmazie, 1998
Synthesis and biological evaluation of new 1,2,5-oxadiazole N-oxide derivatives with potential cy... more Synthesis and biological evaluation of new 1,2,5-oxadiazole N-oxide derivatives with potential cytotoxic effects are described. From the series of compounds tested, compounds 2 and 6 proved to be very active, although non-selective.
Strain and Its Implications in Organic Chemistry, 1989
Vinylcyclopropanes, vinyloxiranes, and vinylaziridines were prepared by either a [2+3] protocol i... more Vinylcyclopropanes, vinyloxiranes, and vinylaziridines were prepared by either a [2+3] protocol involving the additions of the dienolate of ethyl 2-bromocrotonate to enones, aldehydes, and some imines, or by a [4+1] protocol that utilized the intramolecular cycloadditions of diazoketones or azides to 1,3-dienes. The resulting strained 3-membered rings provided, through their energy contents, the necessary driving force for the corresponding rearrangments to annulated cyclopentenes, dihydrofurans, and pyrrolines respectively. The applications of these processes are highlighted in the syntheses of natural products containing five-membered rings. Retigeranic acid, ipomeamarone, and pyrrolizidine diols are the targets of these applications. An approach to the taxane skeleton is also advanced and is based on the ease with which endo vinylcyclopropanes undergo the divinylcyclopropane Cope rearrangement.
Acta Crystallographica Section C Crystal Structure Communications, 1999
ABSTRACT The title compound, C11H16O6, has been synthesized and isolated as the major product of ... more ABSTRACT The title compound, C11H16O6, has been synthesized and isolated as the major product of the osmylation of (5S,6R)-5,6-diacetoxy-1-methyl-1,3-cyclohexadiene. The molecule crystallizes in the monoclinic space group P2(1). The hexene ring exhibits a puckered distorted half-chair conformation, with all the chiral centres (C3, C4, C5 and C6) in the S configuration. One intramolecular and two intermolecular hydrogen bonds stabilize the molecule by the formation of infinite chains along b.
Proceedings of the 14th Brazilian Meeting on Organic Synthesis Proceedings, 2013
Synlett, 1990
... Page 8. 440 Tomas Hudlicky, Gustavo Seoane, John D. Price, Kumar G. Gadamasctti (in part) SYN... more ... Page 8. 440 Tomas Hudlicky, Gustavo Seoane, John D. Price, Kumar G. Gadamasctti (in part) SYNLETT Acknowledgements. ... In addition, Robert P. Short, James O. Frazier, and Frank J. Koszyk are extended special thanks for their roles in the developmental work. ...
Spectroscopy Letters, 1998
... ELECTRON SPIN RESONANCE AND CYCLIC VOLTAMMETRY STUDIES OF NITROFURANE AND NITROTHIOPHENE ANAL... more ... ELECTRON SPIN RESONANCE AND CYCLIC VOLTAMMETRY STUDIES OF NITROFURANE AND NITROTHIOPHENE ANALOGUES OF NIFURTIMOX. C. Olea-Azar', ha Maria Atria', Rossana di Maiof, G. Seoane2 and Hugo Cerecetto2 ...