This Letter describes glycosylation of 4-Nerolidylcatechol (4-NRC) the major secondary metabolite... more This Letter describes glycosylation of 4-Nerolidylcatechol (4-NRC) the major secondary metabolite from Pothomorphe peltata and Pothomorphe umbellata showing remarkable antioxidant, antimalarial, antiinflammatory, and anti-HIV activities. One step biosynthesis was catalyzed by Cunninghamella echinulata ATCC 9245 and the reaction was undertaken in PDSM medium at 27°C, 200 rpm for 96 h. After purification by silica gel flash column chromatography the 4-NRC b-glycoside was identified by ultrahigh resolution mass spectrometry and 1 H NMR. The antioxidant activity was evaluated by differential pulse voltammetry.
Eggs, nymphs (1st-5th instar) and adults of Tibraca limbativentris were challenged by conidial su... more Eggs, nymphs (1st-5th instar) and adults of Tibraca limbativentris were challenged by conidial suspensions of its major fungal pathogen Metarhizium anisopliae in order to assess their susceptibility. The role of chemical defensive compounds from exocrine secretions produced by both nymphs and adults were examined for their participation on M. anisopliae infection. Although insect susceptibility to M. anisopliae followed a dose-dependent manner, adults followed by older nymphs displayed the highest resistance. Eggs were highly susceptible showing >96% fungal infection. Crude extracts isolated from metathoracic scent gland and dorsal abdominal glands of adults and nymphs, respectively, showed fungistatic effects by impairing spore germination, vegetative growth and sporulation. Gas chromatography-mass spectrometry analysis of these extracts revealed that the major components were short-chain hydrocarbons (C10-13) and unsaturated aldehydes. In vitro tests with the corresponding synt...
The pyrazol compounds are known to possess antipyretic, analgesic and anti-inflammatory activitie... more The pyrazol compounds are known to possess antipyretic, analgesic and anti-inflammatory activities. This study was conducted to investigate the peripheral antinociceptive effect of the pyrazole compound 5-(1-(3-Fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole (LQFM-021) and involvement of opioid receptors and of the NO/cGMP/KATP pathway. The oral treatments in mice with LQFM-021 (17, 75 or 300 mg/kg) decreased the number of writhing. In the formalin test, the treatments with LQFM-021 at doses of 15, 30 and 60 mg/kg reduced the licking time at both neurogenic and inflammatory phases of this test. The treatment of the animals with LQFM-021 (30 mg/kg) did not have antinociceptive effects in the tail-flick and hot plate tests. Furthermore, pre-treatment with naloxone (3 mg/kg i.p.), L-name (10 mg/kg i.p.), ODQ (10 mg/kg i.p.) or glibenclamide (3 mg/kg i.p.) antagonized the antinociceptive effect of LQFM-021 in both phases of the formalin test. In addition, it was also demonstrated that the treatments of mice with LQFM-021(15, 30 and 60 mg/kg) did not compromise the motor activity of the animals in the chimney test. Only the highest dose used in the antinociceptive study promoted changes in the open field test and pentobarbital-induced sleep test, thus ruling out possible false positive effects on nociception tests. Our data suggest that the peripheral antinociception effects of the LQFM-021 were mediated through the peripheral opioid receptors with activation of the NO/cGMP/KATP pathway.
The presence of halogen atoms reduces the flexibility of the porphyrinic ring. The protonation wa... more The presence of halogen atoms reduces the flexibility of the porphyrinic ring. The protonation was observed only in extremely acid environment. Chlorinated atoms cause a stronger effect on the fluorescence than fluorinated atoms. Protonation reduces the fluorescence lifetime of sulfonated porphyrins. Protonation causes an enhancement of the absorbance in the therapeutic window.
Two new β -carboline alkaloids, epi-strictosidinic acid (1) and strictosidinic ketone (2), togeth... more Two new β -carboline alkaloids, epi-strictosidinic acid (1) and strictosidinic ketone (2), together with two known alkaloids, calycanthine (3) and strictosidinic acid (4) besides the triterpene ursolic acid (5) were isolated from the roots and leaves of Palicourea coriacea. The structures of the isolates were elucidated on the basis of spectral data, particularly COSY, HMQC and HMBC experiments, and HR mass spectra.
RESUMO: "Efeitos analgésico e antiinÀ amatório das cascas das raízes de Cheiloclinium cognatum". ... more RESUMO: "Efeitos analgésico e antiinÀ amatório das cascas das raízes de Cheiloclinium cognatum". Cheiloclinium cognatum é uma planta da família das Hippocrateaceae, popularmente conhecida como bacupari, usada popularmente no tratamento de febre e edemas. Neste artigo, descrevemos as atividades antiinÀ amatória e analgésica do extrato bruto diclorometânico das cascas das raízes (DECc), coletadas no bosque Auguste de Saint Hilaire, localizado na Universidade Federal de Goiás. Doses de 0,1, 0,3 e 1,0 g/kg causaram uma redução de 21, 30 e 51%, respectivamente, no edema de orelha de camundongos, induzido pelo óleo de cróton. No método algesimétrico, À exão de cauda, observou-se um signi¿ cativo aumento no tempo para reação ao estímulo térmico equivalente a 105, 189 e 200%. Estes resultados sugerem que C. cognatum pode ser uma fonte de novos compostos com atividades antiinÀ amatória e analgésica.
In this paper we report the design, synthesis, antinociceptive and anti-inflammatory activities o... more In this paper we report the design, synthesis, antinociceptive and anti-inflammatory activities of a series of benzothiazine N-acylhydrazones 14a-h, planned by structural modification of piroxicam (1), a non steroidal anti-inflammatory drug. Among the synthesized analogues, compounds 14f (LASSBio-1637) and 14g (LASSBio-1639) were identified as novel antinociceptive and anti-inflammatory prototypes, active by oral administration, acting by a mechanism of action that seems to be different from that of piroxicam, since they were inactive as an inhibitor of cyclooxygenase (COX-1 and COX-2) at concentrations of 10 M.
Virtual screening (VS) techniques are well-established tools in the modern drug discovery process... more Virtual screening (VS) techniques are well-established tools in the modern drug discovery process, mainly used for hit finding in drug discovery. The availability of knowledge of structural information, which includes an increasing number of 3D protein structures and the readiness of free databases of commercially available smallmolecules, provides a broad platform for VS. This review summarizes the current developments in VS regarding chemical databases and highlights the achievements as well as the challenges with an emphasis on a recent example of the successful application for the identification of new hits for sterol 14 -demethylase (CYP51) of Trypanosoma cruzi.
The use of 1H NMR to quantify different methyl biodiesels in diesel from different sources is des... more The use of 1H NMR to quantify different methyl biodiesels in diesel from different sources is described. Biodiesel samples from soybean and castor oils, which have different fatty acid compositions, and three diesel fuels, which have distinct chemical compositions, were used to prepare biodiesel blends (0.5–30%, v/v). These samples were analyzed by 1H NMR and some relationships of integrals were
Power transformers are essential components in electrical energy distribution. One of their most ... more Power transformers are essential components in electrical energy distribution. One of their most important parts is the insulation system, consisting of Kraft paper immersed in insulating oil. Interfacial tension and color are major parameters used for assessing oil quality and the system's degradation. This work proposes the use of near infrared (NIR), molecular fluorescence, and 1 H nuclear magnetic resonance (NMR) spectroscopy methods combined with chemometric multivariate calibration methods (Partial Least Squares -PLS) to predict interfacial tension and color in insulating mineral oil samples. Interfacial tension and color were also determined using tensiometry and colorimetry as standard reference methods, respectively. The best PLS model was obtained when NIR, fluorescence, and NMR data were combined (data fusion), demonstrating synergy among them. An optimal PLS model was calculated using the selected group of variables according to their importance on PLS projections (VIP). The root mean square errors of prediction (RMSEP) values of 2.9 mN m À 1 and 0.3 were estimated for interfacial tension and color, respectively. Mean relative standard deviations of 1.5% for interfacial tension and 6% for color were registered, meeting quality control requirements set by electrical energy companies. The methods proposed in this work are rapid and simple, showing great advantages over traditional approaches, which are slow and environmentally unfriendly due to chemical waste generation.
Biodiesel is an alternative fuel composed of mono-alkyl esters and obtained mainly from the basec... more Biodiesel is an alternative fuel composed of mono-alkyl esters and obtained mainly from the basecatalyzed transesterification reaction of oils or fats. Its use (pure or blended) does not demand any modification in the diesel engine and in the existing fuel distribution and storage infrastructure. Moreover, biodiesel has a high energetic yield, fixes the solar energy and contains insignificant amounts of sulphur. Therefore, biodiesel is currently the best substitute for fossil diesel fuel.
In this work, the use of 1 H NMR spectroscopy and statistical approach to the evaluation of biodi... more In this work, the use of 1 H NMR spectroscopy and statistical approach to the evaluation of biodiesel-diesel blends quality is described. Forty-six mixtures of oil-diesel, biodiesel-diesel, and oil-biodiesel-diesel were analyzed by 1 H NMR and such data were employed to design four predictive models. Thirty-six mixtures were used in the calibration set and the others in the validation. The PCR and PLS models were evaluated through statistical parameters.
CHEMICAL PROFILE OF BEANS CULTIVARS (Phaseolus vulgaris) BY 1H NMR-HIGH RESOLUTION MAGIC ANGLE SP... more CHEMICAL PROFILE OF BEANS CULTIVARS (Phaseolus vulgaris) BY 1H NMR-HIGH RESOLUTION MAGIC ANGLE SPINNING (HR-MAS). The application of one-dimensional proton high-resolution magic angle spinning (1H HR-MAS) NMR combined with a typical ...
This study presents the syntheses and characterization of 2-mercaptopyridine (pyS À ) complexes c... more This study presents the syntheses and characterization of 2-mercaptopyridine (pyS À ) complexes containing ruthenium(II) with the following general formula [Ru(pyS) 2 (P-P)], P-P = (c-dppen) = cis-1, and (dppb) = 1,4-bis(diphenylphosphino)butane (4). The complexes were synthesized from the mer-or fac-[RuCl 3 (NO)(P-P)] precursors in the presence of triethylamine in methanol solution with dependence of the product on the P-P ligand. The reaction of pyS À with a ruthenium complex containing a bulky aromatic diphosphine dppb disclosed a major product with a dangling coordinated dppbO-P, the [Ru(pyS) 2 (NO)(g 1 -dppbO-P)]PF 6 (5). In addition, this work also presents and discusses the spectroscopic and electrochemical behavior of 1-5, and report the X-ray structures for 1 and 5.
An investigation of the methanol and ethyl acetate extracts from the roots of Peritassa campestri... more An investigation of the methanol and ethyl acetate extracts from the roots of Peritassa campestris (Hippocrateaceae) afforded the sesquiterpene pyridine alkaloid, 4-hydroxy-7-epi-chuchuhuanine E-V, and nine known alkaloids, forrestine, euonimine, ebenifoline E-I, wilforine, euojaponine F, euonine, wilforjine, neowilforine, and wilforzine. The structures of the isolates were elucidated on the basis of spectral data, particularly HMQC and HMBC experiments.
The triterpenes, 22b-hydroxypristimerin and cognatine, were isolated together with the known comp... more The triterpenes, 22b-hydroxypristimerin and cognatine, were isolated together with the known compounds pristimerin, maytenin, 20a-hydroxymaytenin, 22b-hydroxymaytenin, netzahualcoyol, netzahualcoyondiol and netzahualcoyone from root bark of Cheiloclinium cognatum. The structures of the isolated compounds were elucidated by interpretation of their spectral data, including gHMQC and gHMBC experiments.The isolates were investigated for their radical scavenging abilities through a spectrophotometric assay involving reduction of 2,2-diphenyl-picryl hydrazyl (DPPH).
This Letter describes glycosylation of 4-Nerolidylcatechol (4-NRC) the major secondary metabolite... more This Letter describes glycosylation of 4-Nerolidylcatechol (4-NRC) the major secondary metabolite from Pothomorphe peltata and Pothomorphe umbellata showing remarkable antioxidant, antimalarial, antiinflammatory, and anti-HIV activities. One step biosynthesis was catalyzed by Cunninghamella echinulata ATCC 9245 and the reaction was undertaken in PDSM medium at 27°C, 200 rpm for 96 h. After purification by silica gel flash column chromatography the 4-NRC b-glycoside was identified by ultrahigh resolution mass spectrometry and 1 H NMR. The antioxidant activity was evaluated by differential pulse voltammetry.
Eggs, nymphs (1st-5th instar) and adults of Tibraca limbativentris were challenged by conidial su... more Eggs, nymphs (1st-5th instar) and adults of Tibraca limbativentris were challenged by conidial suspensions of its major fungal pathogen Metarhizium anisopliae in order to assess their susceptibility. The role of chemical defensive compounds from exocrine secretions produced by both nymphs and adults were examined for their participation on M. anisopliae infection. Although insect susceptibility to M. anisopliae followed a dose-dependent manner, adults followed by older nymphs displayed the highest resistance. Eggs were highly susceptible showing >96% fungal infection. Crude extracts isolated from metathoracic scent gland and dorsal abdominal glands of adults and nymphs, respectively, showed fungistatic effects by impairing spore germination, vegetative growth and sporulation. Gas chromatography-mass spectrometry analysis of these extracts revealed that the major components were short-chain hydrocarbons (C10-13) and unsaturated aldehydes. In vitro tests with the corresponding synt...
The pyrazol compounds are known to possess antipyretic, analgesic and anti-inflammatory activitie... more The pyrazol compounds are known to possess antipyretic, analgesic and anti-inflammatory activities. This study was conducted to investigate the peripheral antinociceptive effect of the pyrazole compound 5-(1-(3-Fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole (LQFM-021) and involvement of opioid receptors and of the NO/cGMP/KATP pathway. The oral treatments in mice with LQFM-021 (17, 75 or 300 mg/kg) decreased the number of writhing. In the formalin test, the treatments with LQFM-021 at doses of 15, 30 and 60 mg/kg reduced the licking time at both neurogenic and inflammatory phases of this test. The treatment of the animals with LQFM-021 (30 mg/kg) did not have antinociceptive effects in the tail-flick and hot plate tests. Furthermore, pre-treatment with naloxone (3 mg/kg i.p.), L-name (10 mg/kg i.p.), ODQ (10 mg/kg i.p.) or glibenclamide (3 mg/kg i.p.) antagonized the antinociceptive effect of LQFM-021 in both phases of the formalin test. In addition, it was also demonstrated that the treatments of mice with LQFM-021(15, 30 and 60 mg/kg) did not compromise the motor activity of the animals in the chimney test. Only the highest dose used in the antinociceptive study promoted changes in the open field test and pentobarbital-induced sleep test, thus ruling out possible false positive effects on nociception tests. Our data suggest that the peripheral antinociception effects of the LQFM-021 were mediated through the peripheral opioid receptors with activation of the NO/cGMP/KATP pathway.
The presence of halogen atoms reduces the flexibility of the porphyrinic ring. The protonation wa... more The presence of halogen atoms reduces the flexibility of the porphyrinic ring. The protonation was observed only in extremely acid environment. Chlorinated atoms cause a stronger effect on the fluorescence than fluorinated atoms. Protonation reduces the fluorescence lifetime of sulfonated porphyrins. Protonation causes an enhancement of the absorbance in the therapeutic window.
Two new β -carboline alkaloids, epi-strictosidinic acid (1) and strictosidinic ketone (2), togeth... more Two new β -carboline alkaloids, epi-strictosidinic acid (1) and strictosidinic ketone (2), together with two known alkaloids, calycanthine (3) and strictosidinic acid (4) besides the triterpene ursolic acid (5) were isolated from the roots and leaves of Palicourea coriacea. The structures of the isolates were elucidated on the basis of spectral data, particularly COSY, HMQC and HMBC experiments, and HR mass spectra.
RESUMO: "Efeitos analgésico e antiinÀ amatório das cascas das raízes de Cheiloclinium cognatum". ... more RESUMO: "Efeitos analgésico e antiinÀ amatório das cascas das raízes de Cheiloclinium cognatum". Cheiloclinium cognatum é uma planta da família das Hippocrateaceae, popularmente conhecida como bacupari, usada popularmente no tratamento de febre e edemas. Neste artigo, descrevemos as atividades antiinÀ amatória e analgésica do extrato bruto diclorometânico das cascas das raízes (DECc), coletadas no bosque Auguste de Saint Hilaire, localizado na Universidade Federal de Goiás. Doses de 0,1, 0,3 e 1,0 g/kg causaram uma redução de 21, 30 e 51%, respectivamente, no edema de orelha de camundongos, induzido pelo óleo de cróton. No método algesimétrico, À exão de cauda, observou-se um signi¿ cativo aumento no tempo para reação ao estímulo térmico equivalente a 105, 189 e 200%. Estes resultados sugerem que C. cognatum pode ser uma fonte de novos compostos com atividades antiinÀ amatória e analgésica.
In this paper we report the design, synthesis, antinociceptive and anti-inflammatory activities o... more In this paper we report the design, synthesis, antinociceptive and anti-inflammatory activities of a series of benzothiazine N-acylhydrazones 14a-h, planned by structural modification of piroxicam (1), a non steroidal anti-inflammatory drug. Among the synthesized analogues, compounds 14f (LASSBio-1637) and 14g (LASSBio-1639) were identified as novel antinociceptive and anti-inflammatory prototypes, active by oral administration, acting by a mechanism of action that seems to be different from that of piroxicam, since they were inactive as an inhibitor of cyclooxygenase (COX-1 and COX-2) at concentrations of 10 M.
Virtual screening (VS) techniques are well-established tools in the modern drug discovery process... more Virtual screening (VS) techniques are well-established tools in the modern drug discovery process, mainly used for hit finding in drug discovery. The availability of knowledge of structural information, which includes an increasing number of 3D protein structures and the readiness of free databases of commercially available smallmolecules, provides a broad platform for VS. This review summarizes the current developments in VS regarding chemical databases and highlights the achievements as well as the challenges with an emphasis on a recent example of the successful application for the identification of new hits for sterol 14 -demethylase (CYP51) of Trypanosoma cruzi.
The use of 1H NMR to quantify different methyl biodiesels in diesel from different sources is des... more The use of 1H NMR to quantify different methyl biodiesels in diesel from different sources is described. Biodiesel samples from soybean and castor oils, which have different fatty acid compositions, and three diesel fuels, which have distinct chemical compositions, were used to prepare biodiesel blends (0.5–30%, v/v). These samples were analyzed by 1H NMR and some relationships of integrals were
Power transformers are essential components in electrical energy distribution. One of their most ... more Power transformers are essential components in electrical energy distribution. One of their most important parts is the insulation system, consisting of Kraft paper immersed in insulating oil. Interfacial tension and color are major parameters used for assessing oil quality and the system's degradation. This work proposes the use of near infrared (NIR), molecular fluorescence, and 1 H nuclear magnetic resonance (NMR) spectroscopy methods combined with chemometric multivariate calibration methods (Partial Least Squares -PLS) to predict interfacial tension and color in insulating mineral oil samples. Interfacial tension and color were also determined using tensiometry and colorimetry as standard reference methods, respectively. The best PLS model was obtained when NIR, fluorescence, and NMR data were combined (data fusion), demonstrating synergy among them. An optimal PLS model was calculated using the selected group of variables according to their importance on PLS projections (VIP). The root mean square errors of prediction (RMSEP) values of 2.9 mN m À 1 and 0.3 were estimated for interfacial tension and color, respectively. Mean relative standard deviations of 1.5% for interfacial tension and 6% for color were registered, meeting quality control requirements set by electrical energy companies. The methods proposed in this work are rapid and simple, showing great advantages over traditional approaches, which are slow and environmentally unfriendly due to chemical waste generation.
Biodiesel is an alternative fuel composed of mono-alkyl esters and obtained mainly from the basec... more Biodiesel is an alternative fuel composed of mono-alkyl esters and obtained mainly from the basecatalyzed transesterification reaction of oils or fats. Its use (pure or blended) does not demand any modification in the diesel engine and in the existing fuel distribution and storage infrastructure. Moreover, biodiesel has a high energetic yield, fixes the solar energy and contains insignificant amounts of sulphur. Therefore, biodiesel is currently the best substitute for fossil diesel fuel.
In this work, the use of 1 H NMR spectroscopy and statistical approach to the evaluation of biodi... more In this work, the use of 1 H NMR spectroscopy and statistical approach to the evaluation of biodiesel-diesel blends quality is described. Forty-six mixtures of oil-diesel, biodiesel-diesel, and oil-biodiesel-diesel were analyzed by 1 H NMR and such data were employed to design four predictive models. Thirty-six mixtures were used in the calibration set and the others in the validation. The PCR and PLS models were evaluated through statistical parameters.
CHEMICAL PROFILE OF BEANS CULTIVARS (Phaseolus vulgaris) BY 1H NMR-HIGH RESOLUTION MAGIC ANGLE SP... more CHEMICAL PROFILE OF BEANS CULTIVARS (Phaseolus vulgaris) BY 1H NMR-HIGH RESOLUTION MAGIC ANGLE SPINNING (HR-MAS). The application of one-dimensional proton high-resolution magic angle spinning (1H HR-MAS) NMR combined with a typical ...
This study presents the syntheses and characterization of 2-mercaptopyridine (pyS À ) complexes c... more This study presents the syntheses and characterization of 2-mercaptopyridine (pyS À ) complexes containing ruthenium(II) with the following general formula [Ru(pyS) 2 (P-P)], P-P = (c-dppen) = cis-1, and (dppb) = 1,4-bis(diphenylphosphino)butane (4). The complexes were synthesized from the mer-or fac-[RuCl 3 (NO)(P-P)] precursors in the presence of triethylamine in methanol solution with dependence of the product on the P-P ligand. The reaction of pyS À with a ruthenium complex containing a bulky aromatic diphosphine dppb disclosed a major product with a dangling coordinated dppbO-P, the [Ru(pyS) 2 (NO)(g 1 -dppbO-P)]PF 6 (5). In addition, this work also presents and discusses the spectroscopic and electrochemical behavior of 1-5, and report the X-ray structures for 1 and 5.
An investigation of the methanol and ethyl acetate extracts from the roots of Peritassa campestri... more An investigation of the methanol and ethyl acetate extracts from the roots of Peritassa campestris (Hippocrateaceae) afforded the sesquiterpene pyridine alkaloid, 4-hydroxy-7-epi-chuchuhuanine E-V, and nine known alkaloids, forrestine, euonimine, ebenifoline E-I, wilforine, euojaponine F, euonine, wilforjine, neowilforine, and wilforzine. The structures of the isolates were elucidated on the basis of spectral data, particularly HMQC and HMBC experiments.
The triterpenes, 22b-hydroxypristimerin and cognatine, were isolated together with the known comp... more The triterpenes, 22b-hydroxypristimerin and cognatine, were isolated together with the known compounds pristimerin, maytenin, 20a-hydroxymaytenin, 22b-hydroxymaytenin, netzahualcoyol, netzahualcoyondiol and netzahualcoyone from root bark of Cheiloclinium cognatum. The structures of the isolated compounds were elucidated by interpretation of their spectral data, including gHMQC and gHMBC experiments.The isolates were investigated for their radical scavenging abilities through a spectrophotometric assay involving reduction of 2,2-diphenyl-picryl hydrazyl (DPPH).
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