Gonzalo Carrau - Academia.edu (original) (raw)
Papers by Gonzalo Carrau
ChemistrySelect, Dec 1, 2017
Bioorganic & Medicinal Chemistry, Jul 1, 2013
A small library of compounds was prepared by a combination of toluene dioxygenase (TDO)-catalyzed... more A small library of compounds was prepared by a combination of toluene dioxygenase (TDO)-catalyzed enzymatic dihydroxylation and copper(I)-catalyzed Hüisgen cycloaddition. Some compounds were obtained by coupling an alkyne and a conduritol derivative, while more complex structures were obtained by a double Hüisgen reaction of a dialkyne and two molecules of the cyclitol. The compounds were fully characterized and subjected to preliminary biological screening.
Letters in Drug Design & Discovery, Nov 1, 2013
The antifungal activity of a library of 32 cyclitols and derivatives, including 6 previously unre... more The antifungal activity of a library of 32 cyclitols and derivatives, including 6 previously unreported cyclitol amino acid conjugates, was studied against the clinically important yeasts Candida albicans, Candida tropicalis and Cryptococcus neoformans along with Saccharomyces cerevisiae. Bioautography followed by standardized microbroth dilution methods were used and allowed to identify an azidoinositol glycoside (11) and an azidoconduritol linked to an aromatic aldehyde (18) as promising compounds. The results suggest the relevance of exploring synthetic cyclitolic structures as potential antifungal leaders.
European Journal of Organic Chemistry, Jan 2, 2019
Journal of the Brazilian Chemical Society, 2015
Molecules
With the objective to develop a potential 99mTc radiopharmaceutical for imaging the androgen rece... more With the objective to develop a potential 99mTc radiopharmaceutical for imaging the androgen receptor (AR) in prostate cancer, four ligands bearing the same pharmacophore derived from the AR antagonist flutamide were prepared, labeled with 99mTc, and their structures corroborated via comparison with the corresponding stable rhenium analogs. All complexes were obtained with high radiochemical purity. Three of the complexes were highly stable, and, due to their favorable physicochemical properties, were further evaluated using AR-positive and AR-negative cells in culture. All complexes exhibited considerable uptake in AR-positive cells, which could be blocked by an excess of flutamide. The efflux from the cells was moderate. They also showed significantly lower uptakes in AR-negative cells, indicating interactions with the AR receptor. However, the binding affinities were considerably reduced by the coordination to 99mTc, and the complex that exhibited the best biological behavior did...
Nuclear Medicine and Biology
Nuclear Medicine and Biology
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
ChemistrySelect, 2017
Recently, we found that the Diels–Alder reaction between levoglucosenone and the acetonide of (1S... more Recently, we found that the Diels–Alder reaction between levoglucosenone and the acetonide of (1S,2R)‐3‐methylcyclohexa‐3,5‐diene‐1,2‐diol occurs through the most hindered face of the diene. This unexpected facial selectivity has no precedent for di‐O‐isopropylidene‐protected dienes, and the reasons behind it remain unclear. Here, we expand on our earlier findings, computationally assessing the structural and electronic factors responsible for this unforeseen stereoselectivity. The B3LYP/6‐31+G(d,p) results identify the three main adducts (β‐endo‐ortho:α‐endo‐meta:α‐exo‐ortho), giving a product ratio (63:9:28) that is in line with the experimental value (64:16:10). The β‐endo attack allows to maximize the electrostatic attraction between the reactants, giving rise to dipolar C−O⋅⋅⋅H−C interactions with the isopropylidene group at the transition state. The endo/exo preference can be rationalized through electrostatic repulsion and steric hindrance between the isopropylidene and methy...
European Journal of Organic Chemistry, 2018
This manuscript describes the enantioselective synthesis of the aminocyclitol moiety of the antib... more This manuscript describes the enantioselective synthesis of the aminocyclitol moiety of the antibiotic hygromycin A in eight steps and 39 % overall yield from a non‐chiral starting material. The sequence made use of an initial enzymatic step to transfer chirality to an aromatic ring and was followed by selective organic chemistry transformations (oxidation, protection, azidation, hydrolysis) of the six‐membered ring in order to achieve the target. The approach is also amenable to the synthesis of other related unnatural analogues as exemplified by the synthesis of the C2 epimer of the natural aminocyclitol. All the intermediates were fully characterized, and the absolute stereochemistry assigned by spectrometric methods.
Tetrahedron Letters, 2016
Diels–Alder cycloaddition between an enantiomerically pure protected cis-cyclohexadiene diol meta... more Diels–Alder cycloaddition between an enantiomerically pure protected cis-cyclohexadiene diol metabolite and optically pure levoglucosenone derived from cellulose gave rise to complex pentacyclic natural product like structures in a chemically succinct process. The adducts were fully characterized and the observed results were in accord with theoretical calculations performed on the possible course of the reaction.
Journal of the Brazilian Chemical Society, 2015
World Journal of Chemical Education, 2015
ChemistrySelect, Dec 1, 2017
Bioorganic & Medicinal Chemistry, Jul 1, 2013
A small library of compounds was prepared by a combination of toluene dioxygenase (TDO)-catalyzed... more A small library of compounds was prepared by a combination of toluene dioxygenase (TDO)-catalyzed enzymatic dihydroxylation and copper(I)-catalyzed Hüisgen cycloaddition. Some compounds were obtained by coupling an alkyne and a conduritol derivative, while more complex structures were obtained by a double Hüisgen reaction of a dialkyne and two molecules of the cyclitol. The compounds were fully characterized and subjected to preliminary biological screening.
Letters in Drug Design & Discovery, Nov 1, 2013
The antifungal activity of a library of 32 cyclitols and derivatives, including 6 previously unre... more The antifungal activity of a library of 32 cyclitols and derivatives, including 6 previously unreported cyclitol amino acid conjugates, was studied against the clinically important yeasts Candida albicans, Candida tropicalis and Cryptococcus neoformans along with Saccharomyces cerevisiae. Bioautography followed by standardized microbroth dilution methods were used and allowed to identify an azidoinositol glycoside (11) and an azidoconduritol linked to an aromatic aldehyde (18) as promising compounds. The results suggest the relevance of exploring synthetic cyclitolic structures as potential antifungal leaders.
European Journal of Organic Chemistry, Jan 2, 2019
Journal of the Brazilian Chemical Society, 2015
Molecules
With the objective to develop a potential 99mTc radiopharmaceutical for imaging the androgen rece... more With the objective to develop a potential 99mTc radiopharmaceutical for imaging the androgen receptor (AR) in prostate cancer, four ligands bearing the same pharmacophore derived from the AR antagonist flutamide were prepared, labeled with 99mTc, and their structures corroborated via comparison with the corresponding stable rhenium analogs. All complexes were obtained with high radiochemical purity. Three of the complexes were highly stable, and, due to their favorable physicochemical properties, were further evaluated using AR-positive and AR-negative cells in culture. All complexes exhibited considerable uptake in AR-positive cells, which could be blocked by an excess of flutamide. The efflux from the cells was moderate. They also showed significantly lower uptakes in AR-negative cells, indicating interactions with the AR receptor. However, the binding affinities were considerably reduced by the coordination to 99mTc, and the complex that exhibited the best biological behavior did...
Nuclear Medicine and Biology
Nuclear Medicine and Biology
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
ChemistrySelect, 2017
Recently, we found that the Diels–Alder reaction between levoglucosenone and the acetonide of (1S... more Recently, we found that the Diels–Alder reaction between levoglucosenone and the acetonide of (1S,2R)‐3‐methylcyclohexa‐3,5‐diene‐1,2‐diol occurs through the most hindered face of the diene. This unexpected facial selectivity has no precedent for di‐O‐isopropylidene‐protected dienes, and the reasons behind it remain unclear. Here, we expand on our earlier findings, computationally assessing the structural and electronic factors responsible for this unforeseen stereoselectivity. The B3LYP/6‐31+G(d,p) results identify the three main adducts (β‐endo‐ortho:α‐endo‐meta:α‐exo‐ortho), giving a product ratio (63:9:28) that is in line with the experimental value (64:16:10). The β‐endo attack allows to maximize the electrostatic attraction between the reactants, giving rise to dipolar C−O⋅⋅⋅H−C interactions with the isopropylidene group at the transition state. The endo/exo preference can be rationalized through electrostatic repulsion and steric hindrance between the isopropylidene and methy...
European Journal of Organic Chemistry, 2018
This manuscript describes the enantioselective synthesis of the aminocyclitol moiety of the antib... more This manuscript describes the enantioselective synthesis of the aminocyclitol moiety of the antibiotic hygromycin A in eight steps and 39 % overall yield from a non‐chiral starting material. The sequence made use of an initial enzymatic step to transfer chirality to an aromatic ring and was followed by selective organic chemistry transformations (oxidation, protection, azidation, hydrolysis) of the six‐membered ring in order to achieve the target. The approach is also amenable to the synthesis of other related unnatural analogues as exemplified by the synthesis of the C2 epimer of the natural aminocyclitol. All the intermediates were fully characterized, and the absolute stereochemistry assigned by spectrometric methods.
Tetrahedron Letters, 2016
Diels–Alder cycloaddition between an enantiomerically pure protected cis-cyclohexadiene diol meta... more Diels–Alder cycloaddition between an enantiomerically pure protected cis-cyclohexadiene diol metabolite and optically pure levoglucosenone derived from cellulose gave rise to complex pentacyclic natural product like structures in a chemically succinct process. The adducts were fully characterized and the observed results were in accord with theoretical calculations performed on the possible course of the reaction.
Journal of the Brazilian Chemical Society, 2015
World Journal of Chemical Education, 2015