Natural products are an important source of bioactive molecules. However, the development of biol... more Natural products are an important source of bioactive molecules. However, the development of biological applications based on these compounds is hindered by intrinsic problems in their solubility, volatility, degradation, and bioavailability. Nanocarriers as drug administration systems promise to overcome these limitations by providing controlled and directed delivery. This review aims to present 1) the most frequently used nanocarriers as natural product administration systems, based on the progress of controlled and directed release, and 2) the challenges associated with the use of nanocarriers as therapeutic agents.
Candida albicans is the most commonly implicated agent in invasive human fungal infections. The d... more Candida albicans is the most commonly implicated agent in invasive human fungal infections. The disease could be presented as minimal symptomatic candidemia or can be fulminant sepsis. Candidemia is associated with a high rate of mortality and high healthcare and hospitalization costs. The surveillance programs have reported the distribution of other Candida species reflecting the trends and antifungal susceptibilities. Previous studies have demonstrated that C. glabrata more frequently presents fluconazole-resistant strains. Extracts from Mexican plants have been reported with activity against pulmonary mycosis, among them Colubrina greggii. In the present study, extracts from the aerial parts (leaves, flowers, and fruits) of this plant were evaluated against clinical isolates of several species of Candida (C. albicans, C. glabrata, C. parapsilosis, C. krusei, and C. tropicalis) by the broth microdilution assay. Through bioassay-guided fractionation, three antifungal glycosylated f...
The cyclopropane ring-opening reaction of riolozatrione, a natural product obtained from Jatropha... more The cyclopropane ring-opening reaction of riolozatrione, a natural product obtained from Jatropha dioica, afforded a 2,2-disubstituted 1,3-cyclohexandione displaying an alkyl methyl ether group at position 5. The conformational analysis of this product showed a high preference for the trans-diaxial conformation in both solution and solid state. Such conformation was possible from the noncovalent intramolecular nX → π*C═O interactions (X = an element having an unshared electron pair), allowing the determination of the interaction energies. Since the nX → π*C═O interactions can be regarded as additive, the energy values ranged from 4.52 to 6.51 kcal mol-1 for each carbonyl group with a strong dependency on the interatomic distances. The rigorous analysis of the electron density in the topological theory of atoms in molecules framework clearly shows that the origin of O-C═O interactions are through the nO → π*C═O electron transfer mechanism. Such interactions are slightly weaker than a canonical hydrogen bond but seemingly stronger than a van der Waals interaction. This interaction must be considered as a stereoelectronic effect due the electronic transfer between the interacting groups, which are limited by their relative stereochemistry and can be represented by a bond-no bond interaction, causing the pyramidalization of the carbonyl, which is the charge acceptor group.
Cissus incisa is used in traditional Mexican medicine to treat certain ailments, infectious or ca... more Cissus incisa is used in traditional Mexican medicine to treat certain ailments, infectious or cancerous diseases. Excepting for our previous research, this species had no scientific reports validating its traditional use. In this study, we evaluated the antibacterial and cytotoxic properties of the sphingolipids and others phytocompounds isolated from C. incisa leaves to increase the scientific knowledge of the Mexican flora. The antibacterial activity was evaluated against Gram-positive and Gram-negative bacteria by the Microdilution method. Meanwhile, the cytotoxic potential was determined on six human cancer cells: PC3, Hep3B, HepG2, MCF7, A549, and HeLa; using an aqueous solution cell proliferation assay kit. A cell line of immortalized human hepatocytes (IHH) was included as a control of non-cancerous cells. Selectivity index (SI) was determined only against the hepatocellular carcinoma cell lines. The phytochemical investigation of C. incisa leaves resulted in the isolation and characterization of five compounds: 2-(2′-hydroxydecanoyl amino)-1,3,4-hexadecanotriol-8-ene (1), 2,3-dihydroxypropyl tetracosanoate (2), β-sitosterol-D-glucopyranoside (3), α-amyrin-3-O-β-D-glucopyranoside (4), and a mixture of cerebrosides (5). Until now, this is the first report of the sphingolipids (1), (5-IV) and (5-V). Only the compound (4) and cerebrosides (5) exhibited antibacterial activity reaching a MIC value of 100 μg/mL against Pseudomonas aeruginosa resistant to carbapenems. While, the acetylated derivate of (3), compound (3Ac) showed the best cytotoxic result against PC3 (IC50 = 43 ± 4 μg/mL) and Hep3B (IC50 = 49.0 ± 4 μg/mL) cancer cell lines. Likewise, (3Ac) achieved better SI values on HepG2 and Hep3B cell lines. This research reveals the importance of study medicinal plants, to identify bioactive molecules as sources of potential drugs. The presence of these compounds allows us to justify the use of this plant in traditional Mexican medicine.
Endoperoxides have received widespread interest as a research topic due to its ubiquitous structu... more Endoperoxides have received widespread interest as a research topic due to its ubiquitous structure, which confers interesting biological properties. It has been demonstrated that some endoperoxides possess antimalarial, cytotoxic, anti-inflammatory, neuroprotective, antiparasitic, antitumor, and antimicrobial activities. The present review summarizes the current knowledge about the structure, occurrence, peroxide detection methods, stability, biosynthesis, and biological activities of 206 endoperoxides isolated from 1911 to 2019, found in 115 plant species belonging to 36 different plant families. Thirty-five new endoperoxides of different plant species have been reported since the last published review. In order to simplify our analysis, we classified plant endoperoxides considering the nature of the secondary metabolite.
Hechtia glomerata Zucc. is used both as a source of food and in ethnomedicine to treat various di... more Hechtia glomerata Zucc. is used both as a source of food and in ethnomedicine to treat various diseases derived from bacterial infections such as bronchitis, laryngitis, nephritis, whooping cough, urethritis, and sepsis. There are no previous reports about its chemistry and biological activities. Therefore, the aims of this study were to identify components from organic and aqueous extracts of H. glomerata and test the extracts and major isolate compounds against resistant bacteria. Hexane, CHCl3/MeOH, and aqueous extracts were prepared and analyzed by different chromatographic techniques. Structural elucidation was carried out by NMR spectroscopy and X-ray diffraction. The antibacterial activities of extracts, phytochemicals, and semisynthetic derivatives against resistant bacteria were determined by the broth micro-dilution method. From the hexane extract nonacosane (1), hexatriacontanyl stearate (2), hexacosanol (3), oleic acid (4), and β-sitosterol (5) were isolated and characte...
The synthesis of two series of α-aminophosphonates was achieved by Microwave Irradiation (MW), us... more The synthesis of two series of α-aminophosphonates was achieved by Microwave Irradiation (MW), using the one-pot Kabachnik–Fields reaction. Based on a green chemistry approach, the reactions were carried out using ethanol as the only solvent and without any catalyst, and short reaction times (20–40 min), in variable yields. Both series were tested to determine their cell proliferation inhibition activity in MDA-MB-231, MCF-7 and MCF-10A cell lines. Ethyl 4-(((diphenoxyphosphoryl)(4-(diphenylamino)phenyl)methyl)amino) benzoate 4e and diphenyl (((4-(((S)-2-hydroxy-1-phenylethyl)carbamoyl)phenyl)amino)(4-hydroxyphenyl)methyl)phosphonate 6b, showed cell proliferation inhibition activity only in the cancer cell line MCF-7 and no effect on the normal cell line MFC-10A, both compounds caused cell death by inducing apoptosis.
Herpes simplex is a disease that is widely distributed throughout the world. It is caused by herp... more Herpes simplex is a disease that is widely distributed throughout the world. It is caused by herpes simplex virus type 1 (HSV-1) and simplex virus type 2 (HSV-2). The drugs of choice for treatment are acyclovir (ACV), Penciclovir (PCV) and other guanine analogues, which have the same mechanism of action. However, due to the constant increase of ACV-resistant strains in immunocompromised patients, it is necessary to find new treatment alternatives. It has been shown that natural products are a good alternative for the treatment of these diseases as well as being an excellent source of compounds with anti-herpetic activity, which may be useful for the development of new drugs and act through a mechanism of action different from ACV and PCV. This paper compiles reports on extracts and compounds isolated from plants that have anti-herpetic activity. We present an analysis of the solvents most widely used for extraction from plants as well as cells and commonly used methods for evaluatin...
Abstract In recent years, the demand for rebaudioside A (Reb A) in the food industry has increase... more Abstract In recent years, the demand for rebaudioside A (Reb A) in the food industry has increased due to its sweetening power and organoleptic properties. Currently, there is a large variety of food products on the market for human consumption containing Reb A, and among them, sweeteners stand out. In the present work, a strategy for the quantification of Reb A in commercial sweeteners using quantitative 1H nuclear magnetic resonance (qHNMR) with an external standard method applying the pulse length–based concentration determination (ERETIC2) is described. The developed qHNMR method notably satisfies the validation parameters, such as linearity, precision, accuracy, reproducibility, robustness, limit of detection, and limit of quantification (LOQ). The lineal range was established between 0.3–14.8 mM. The LOQ (0.3 mM) was sufficiently low to assess the quantification of Reb A in analysed samples. Intraday and intermediate precision were evaluated in different matrices and the percent relative standard deviation (%RSD) founded were lower than 1.93, and 2.79, respectively. Additionally, this qHNMR procedure has advantages such as a fast analysis time, easy sample preparation and low generation of solvent waste, which represents an environmentally responsible analytical alternative for the determination of Reb A in commercial sweeteners.
In the present article we describe the spectroscopic data of 1H and 13C Nuclear Magnetic Resonanc... more In the present article we describe the spectroscopic data of 1H and 13C Nuclear Magnetic Resonance of 11 compounds including: Nine natural products from the hexanic-chloroformic and methanolic extracts of Acacia farnesiana fruit and two esterified derivatives (22E-stimasta-5,22-dien- 3β-acetyl and methyl 3,4,5-triacetyloxybenzoate). Data linked to the research work entitled "Chemical composition of fruits of Acacia farnesiana (L) Willd and its activity against Mycobacterium tuberculosis and dysentery bacteria" (Hernández et al., 2019) [1].
In Mexico, plants are an important element of traditional medicine, and many are considered part ... more In Mexico, plants are an important element of traditional medicine, and many are considered part of Mexican cultural heritage from prehispanic and colonial times. Nevertheless, relatively few systematic scientific studies have been conducted to fully characterize the chemical composition and pharmacological activities of Mexican medicinal plants. Acacia farnesiana is used in Mexican traditional medicine to treat dysentery and tuberculosis and therefore could have bioactive compounds that may explain its traditional use. i) To isolate and characterize the compounds from the hexanic, chloroformic and methanolic extracts; ii) to identify the volatile compounds from methylated hexanic and chloroformic extracts using GC-FID and GC-MS methods; iii) to identify the compounds from methanolic and aqueous extracts using HPLC-Q-TOF-MS; iv) to test the activity of extracts and isolated compounds against Mycobacterium tuberculosis and dysentery bacteria. A. farnesiana fruits were collected in Acatlán de Osorio, Puebla, Mexico. Hexanic, chloroformic, methanolic and aqueous extracts were prepared and analyzed by different chromatographic techniques including column chromatography, flash chromatography, GC-FID, GC-MS and HPLC-Q-TOF-MS. Structural elucidation was carried out by NMR spectroscopic analysis. The activity of extracts, phytochemicals and semi-synthetic derivatives against Mycobacterium tuberculosis H37Rv and G122 as well as dysentery bacteria (Campylobacter jejuni, Shigella flexneri, Salmonella enteritidis, Yersinia enterocolitica and enterohemorrhagic Escherichia coli) was determined by the broth microdilution method and reported as minimal inhibitory concentration (MIC µg/mL). From both hexane and chloroform extracts, tetracosanoic acid (2S)-2,3-dihydroxypropyl ester (1) and (3β,22E)-estigmasta-5,22-dien-3-yl β-D-glucopyranoside (2) were isolated and characterized. From the methanolic extract, methyl gallate (3), gallic acid (4), (3β,22E)-estigmasta-5,22-dien-3-yl β-D-glucopyranoside (2), (2S) naringenin 7-O-β-glucopyranoside (prunin, 5), pinitol (6) and sucrose (7) were isolated and characterized. Furthermore, hexanic and chloroformic extracts were analyzed by GC-FID and GC-MS and 18 methylated fatty acids were identified for each extract in addition to three sterols. The methanolic and aqueous extracts were analyzed separately by HPLC-Q-TOF-MS, and 15 compounds were identified in each extract. The compounds 1, 2, and 7, in addition to 13 fatty acids and eight phenolic compounds, were identified for the first time in A. farnesiana. The extracts showed antitubercular (MIC 100-200 µg/mL) and antidysentery activity (MIC 100-200 µg/mL). Methyl gallate and its acetylated derivative showed activity against the sensible strain M. tuberculosis H37Rv with MIC values of 50-25 µg/mL, respectively. The flavanone prunin showed activity against multidrug resistant M. tuberculosis G122 (MIC 50 μg/mL). Methyl gallate, gallic acid and prunin showed activity against C. jejuni (MIC 50 μg/mL). The activity of tested extracts and isolated compounds against M. tuberculosis and dysentery bacteria justifies the ethnomedical use of A. farnesiana fruits for the treatment of tuberculosis and dysentery.
The dichloromethane extract of the roots of Jatropha dioica afforded riolozatrione (1) and a C-6 ... more The dichloromethane extract of the roots of Jatropha dioica afforded riolozatrione (1) and a C-6 epimer of riolozatrione, 6-epi-riolozatrione (2), as a new structure and only the second reported riolozane diterpenoid. The two known diterpenoids jatrophatrione (3) and citlalitrione (4) were also isolated and characterized. Both epimers 1 and 2 are genuine plant constituents, with 2 likely being the biosynthesis precursor of 1 due to the tendency for the quantitative transformation of 2 into 1 under base catalysis. The structural characterization and distinction of the stereoisomers utilized (1)H iterative full-spin analysis, yielding complete J-correlation maps that were represented as quantum interaction and linkage tables. The absolute configuration of compounds 1-4 was established by means of vibrational circular dichroism and via X-ray diffraction analysis for 1, 2, and 4. Additionally, the cytotoxic and antiherpetic in vitro activities of the isolates were evaluated.
Thirty-three meso-dihydroguaiaretic acid (meso-DGA) derivatives bearing esters, ethers, and amino... more Thirty-three meso-dihydroguaiaretic acid (meso-DGA) derivatives bearing esters, ethers, and amino-ethers were synthesized. All derivatives were tested against twelve drug-resistant clinical isolates of Gram-positive and Gram-negative bacteria, including sensitive (H37Rv) and multidrug-resistant Mycobacterium tuberculosis strains. Among the tested compounds, four esters (7, 11, 13, and 17), one ether (23), and three amino-ethers (30, 31, and 33) exhibited moderate activity against methicillin-resistant Staphylococcus aureus, whereas 30 and 31 showed better results than levofloxacin against vancomycin-resistant Enterococcus faecium. Additionally, nineteen meso-DGA derivatives displayed moderate to potent activity against M. tuberculosis H37Rv with minimum inhibitory concentration (MIC) values ranging from 3.125 to 50µg/mL. Seven meso-DGA derivatives bearing amino-ethers (26-31 and 33) exhibited the lowest MICs against M. tuberculosis H37Rv and G122 strains, with 31 being as potent as ...
Proceedings of The 20th International Electronic Conference on Synthetic Organic Chemistry, 2016
Riolozatrione is a natural diterpene isolated from Jatropha dioica to which antiherpetic activity... more Riolozatrione is a natural diterpene isolated from Jatropha dioica to which antiherpetic activity is attributed. Riolozatrione possess a unique diterpene core attractive for chemical modification. In this work, 5 new derivatives were obtained by chemical reduction and cyclopropane ring-opening. NMR techniques where used for the structural characterization. One and two-dimension NMR experiments (COSY, HMBC, HSQC, and NOE) confirm the structures of 5 new riolozatrione derivatives. Anti-herpetic activity was improved by chemical modification in some derivatives.
ABSTRACT Novel tetrahydroindeno[1,2-b]pyrrolidines were conveniently prepared in moderate to good... more ABSTRACT Novel tetrahydroindeno[1,2-b]pyrrolidines were conveniently prepared in moderate to good yields via a sequential Ugi multicomponent reaction or Staudinger/aza-Wittig/Ugi combination, followed by the palladium-catalyzed aerobic oxidative cyclization of the resulting Ugi adducts. GRAPHICAL ABSTRACT
El herpes es una enfermedad emergente, causada por la infección del virus herpes simplex tipo 1 (... more El herpes es una enfermedad emergente, causada por la infección del virus herpes simplex tipo 1 (VHS-1) y tipo 2 (VHS-2) en células de tejido mucoso. Aunque actualmente existen medicamentos para tratar esta enfermedad, se ha observado una emergente aparición de cepas resistentes en pacientes inmunocomprometidos, denotando la importancia de descubrir nuevos compuestos con actividad antiherpética. En México, es amplio el conocimiento de plantas medicinales, estas plantas son conocidas por ser fuente de nuevos medicamentos con actividades terapéuticas como la antiherpética 1. Dentro de estas plantas Juglans mollis, Persea americana, Hamelia patens, Salvia texana, Salvia ballotaeflora y Ceanothus coeruleus se encuentran en el noreste de México. MATERIALES Y MÉTODOS:
Natural products are an important source of bioactive molecules. However, the development of biol... more Natural products are an important source of bioactive molecules. However, the development of biological applications based on these compounds is hindered by intrinsic problems in their solubility, volatility, degradation, and bioavailability. Nanocarriers as drug administration systems promise to overcome these limitations by providing controlled and directed delivery. This review aims to present 1) the most frequently used nanocarriers as natural product administration systems, based on the progress of controlled and directed release, and 2) the challenges associated with the use of nanocarriers as therapeutic agents.
Candida albicans is the most commonly implicated agent in invasive human fungal infections. The d... more Candida albicans is the most commonly implicated agent in invasive human fungal infections. The disease could be presented as minimal symptomatic candidemia or can be fulminant sepsis. Candidemia is associated with a high rate of mortality and high healthcare and hospitalization costs. The surveillance programs have reported the distribution of other Candida species reflecting the trends and antifungal susceptibilities. Previous studies have demonstrated that C. glabrata more frequently presents fluconazole-resistant strains. Extracts from Mexican plants have been reported with activity against pulmonary mycosis, among them Colubrina greggii. In the present study, extracts from the aerial parts (leaves, flowers, and fruits) of this plant were evaluated against clinical isolates of several species of Candida (C. albicans, C. glabrata, C. parapsilosis, C. krusei, and C. tropicalis) by the broth microdilution assay. Through bioassay-guided fractionation, three antifungal glycosylated f...
The cyclopropane ring-opening reaction of riolozatrione, a natural product obtained from Jatropha... more The cyclopropane ring-opening reaction of riolozatrione, a natural product obtained from Jatropha dioica, afforded a 2,2-disubstituted 1,3-cyclohexandione displaying an alkyl methyl ether group at position 5. The conformational analysis of this product showed a high preference for the trans-diaxial conformation in both solution and solid state. Such conformation was possible from the noncovalent intramolecular nX → π*C═O interactions (X = an element having an unshared electron pair), allowing the determination of the interaction energies. Since the nX → π*C═O interactions can be regarded as additive, the energy values ranged from 4.52 to 6.51 kcal mol-1 for each carbonyl group with a strong dependency on the interatomic distances. The rigorous analysis of the electron density in the topological theory of atoms in molecules framework clearly shows that the origin of O-C═O interactions are through the nO → π*C═O electron transfer mechanism. Such interactions are slightly weaker than a canonical hydrogen bond but seemingly stronger than a van der Waals interaction. This interaction must be considered as a stereoelectronic effect due the electronic transfer between the interacting groups, which are limited by their relative stereochemistry and can be represented by a bond-no bond interaction, causing the pyramidalization of the carbonyl, which is the charge acceptor group.
Cissus incisa is used in traditional Mexican medicine to treat certain ailments, infectious or ca... more Cissus incisa is used in traditional Mexican medicine to treat certain ailments, infectious or cancerous diseases. Excepting for our previous research, this species had no scientific reports validating its traditional use. In this study, we evaluated the antibacterial and cytotoxic properties of the sphingolipids and others phytocompounds isolated from C. incisa leaves to increase the scientific knowledge of the Mexican flora. The antibacterial activity was evaluated against Gram-positive and Gram-negative bacteria by the Microdilution method. Meanwhile, the cytotoxic potential was determined on six human cancer cells: PC3, Hep3B, HepG2, MCF7, A549, and HeLa; using an aqueous solution cell proliferation assay kit. A cell line of immortalized human hepatocytes (IHH) was included as a control of non-cancerous cells. Selectivity index (SI) was determined only against the hepatocellular carcinoma cell lines. The phytochemical investigation of C. incisa leaves resulted in the isolation and characterization of five compounds: 2-(2′-hydroxydecanoyl amino)-1,3,4-hexadecanotriol-8-ene (1), 2,3-dihydroxypropyl tetracosanoate (2), β-sitosterol-D-glucopyranoside (3), α-amyrin-3-O-β-D-glucopyranoside (4), and a mixture of cerebrosides (5). Until now, this is the first report of the sphingolipids (1), (5-IV) and (5-V). Only the compound (4) and cerebrosides (5) exhibited antibacterial activity reaching a MIC value of 100 μg/mL against Pseudomonas aeruginosa resistant to carbapenems. While, the acetylated derivate of (3), compound (3Ac) showed the best cytotoxic result against PC3 (IC50 = 43 ± 4 μg/mL) and Hep3B (IC50 = 49.0 ± 4 μg/mL) cancer cell lines. Likewise, (3Ac) achieved better SI values on HepG2 and Hep3B cell lines. This research reveals the importance of study medicinal plants, to identify bioactive molecules as sources of potential drugs. The presence of these compounds allows us to justify the use of this plant in traditional Mexican medicine.
Endoperoxides have received widespread interest as a research topic due to its ubiquitous structu... more Endoperoxides have received widespread interest as a research topic due to its ubiquitous structure, which confers interesting biological properties. It has been demonstrated that some endoperoxides possess antimalarial, cytotoxic, anti-inflammatory, neuroprotective, antiparasitic, antitumor, and antimicrobial activities. The present review summarizes the current knowledge about the structure, occurrence, peroxide detection methods, stability, biosynthesis, and biological activities of 206 endoperoxides isolated from 1911 to 2019, found in 115 plant species belonging to 36 different plant families. Thirty-five new endoperoxides of different plant species have been reported since the last published review. In order to simplify our analysis, we classified plant endoperoxides considering the nature of the secondary metabolite.
Hechtia glomerata Zucc. is used both as a source of food and in ethnomedicine to treat various di... more Hechtia glomerata Zucc. is used both as a source of food and in ethnomedicine to treat various diseases derived from bacterial infections such as bronchitis, laryngitis, nephritis, whooping cough, urethritis, and sepsis. There are no previous reports about its chemistry and biological activities. Therefore, the aims of this study were to identify components from organic and aqueous extracts of H. glomerata and test the extracts and major isolate compounds against resistant bacteria. Hexane, CHCl3/MeOH, and aqueous extracts were prepared and analyzed by different chromatographic techniques. Structural elucidation was carried out by NMR spectroscopy and X-ray diffraction. The antibacterial activities of extracts, phytochemicals, and semisynthetic derivatives against resistant bacteria were determined by the broth micro-dilution method. From the hexane extract nonacosane (1), hexatriacontanyl stearate (2), hexacosanol (3), oleic acid (4), and β-sitosterol (5) were isolated and characte...
The synthesis of two series of α-aminophosphonates was achieved by Microwave Irradiation (MW), us... more The synthesis of two series of α-aminophosphonates was achieved by Microwave Irradiation (MW), using the one-pot Kabachnik–Fields reaction. Based on a green chemistry approach, the reactions were carried out using ethanol as the only solvent and without any catalyst, and short reaction times (20–40 min), in variable yields. Both series were tested to determine their cell proliferation inhibition activity in MDA-MB-231, MCF-7 and MCF-10A cell lines. Ethyl 4-(((diphenoxyphosphoryl)(4-(diphenylamino)phenyl)methyl)amino) benzoate 4e and diphenyl (((4-(((S)-2-hydroxy-1-phenylethyl)carbamoyl)phenyl)amino)(4-hydroxyphenyl)methyl)phosphonate 6b, showed cell proliferation inhibition activity only in the cancer cell line MCF-7 and no effect on the normal cell line MFC-10A, both compounds caused cell death by inducing apoptosis.
Herpes simplex is a disease that is widely distributed throughout the world. It is caused by herp... more Herpes simplex is a disease that is widely distributed throughout the world. It is caused by herpes simplex virus type 1 (HSV-1) and simplex virus type 2 (HSV-2). The drugs of choice for treatment are acyclovir (ACV), Penciclovir (PCV) and other guanine analogues, which have the same mechanism of action. However, due to the constant increase of ACV-resistant strains in immunocompromised patients, it is necessary to find new treatment alternatives. It has been shown that natural products are a good alternative for the treatment of these diseases as well as being an excellent source of compounds with anti-herpetic activity, which may be useful for the development of new drugs and act through a mechanism of action different from ACV and PCV. This paper compiles reports on extracts and compounds isolated from plants that have anti-herpetic activity. We present an analysis of the solvents most widely used for extraction from plants as well as cells and commonly used methods for evaluatin...
Abstract In recent years, the demand for rebaudioside A (Reb A) in the food industry has increase... more Abstract In recent years, the demand for rebaudioside A (Reb A) in the food industry has increased due to its sweetening power and organoleptic properties. Currently, there is a large variety of food products on the market for human consumption containing Reb A, and among them, sweeteners stand out. In the present work, a strategy for the quantification of Reb A in commercial sweeteners using quantitative 1H nuclear magnetic resonance (qHNMR) with an external standard method applying the pulse length–based concentration determination (ERETIC2) is described. The developed qHNMR method notably satisfies the validation parameters, such as linearity, precision, accuracy, reproducibility, robustness, limit of detection, and limit of quantification (LOQ). The lineal range was established between 0.3–14.8 mM. The LOQ (0.3 mM) was sufficiently low to assess the quantification of Reb A in analysed samples. Intraday and intermediate precision were evaluated in different matrices and the percent relative standard deviation (%RSD) founded were lower than 1.93, and 2.79, respectively. Additionally, this qHNMR procedure has advantages such as a fast analysis time, easy sample preparation and low generation of solvent waste, which represents an environmentally responsible analytical alternative for the determination of Reb A in commercial sweeteners.
In the present article we describe the spectroscopic data of 1H and 13C Nuclear Magnetic Resonanc... more In the present article we describe the spectroscopic data of 1H and 13C Nuclear Magnetic Resonance of 11 compounds including: Nine natural products from the hexanic-chloroformic and methanolic extracts of Acacia farnesiana fruit and two esterified derivatives (22E-stimasta-5,22-dien- 3β-acetyl and methyl 3,4,5-triacetyloxybenzoate). Data linked to the research work entitled "Chemical composition of fruits of Acacia farnesiana (L) Willd and its activity against Mycobacterium tuberculosis and dysentery bacteria" (Hernández et al., 2019) [1].
In Mexico, plants are an important element of traditional medicine, and many are considered part ... more In Mexico, plants are an important element of traditional medicine, and many are considered part of Mexican cultural heritage from prehispanic and colonial times. Nevertheless, relatively few systematic scientific studies have been conducted to fully characterize the chemical composition and pharmacological activities of Mexican medicinal plants. Acacia farnesiana is used in Mexican traditional medicine to treat dysentery and tuberculosis and therefore could have bioactive compounds that may explain its traditional use. i) To isolate and characterize the compounds from the hexanic, chloroformic and methanolic extracts; ii) to identify the volatile compounds from methylated hexanic and chloroformic extracts using GC-FID and GC-MS methods; iii) to identify the compounds from methanolic and aqueous extracts using HPLC-Q-TOF-MS; iv) to test the activity of extracts and isolated compounds against Mycobacterium tuberculosis and dysentery bacteria. A. farnesiana fruits were collected in Acatlán de Osorio, Puebla, Mexico. Hexanic, chloroformic, methanolic and aqueous extracts were prepared and analyzed by different chromatographic techniques including column chromatography, flash chromatography, GC-FID, GC-MS and HPLC-Q-TOF-MS. Structural elucidation was carried out by NMR spectroscopic analysis. The activity of extracts, phytochemicals and semi-synthetic derivatives against Mycobacterium tuberculosis H37Rv and G122 as well as dysentery bacteria (Campylobacter jejuni, Shigella flexneri, Salmonella enteritidis, Yersinia enterocolitica and enterohemorrhagic Escherichia coli) was determined by the broth microdilution method and reported as minimal inhibitory concentration (MIC µg/mL). From both hexane and chloroform extracts, tetracosanoic acid (2S)-2,3-dihydroxypropyl ester (1) and (3β,22E)-estigmasta-5,22-dien-3-yl β-D-glucopyranoside (2) were isolated and characterized. From the methanolic extract, methyl gallate (3), gallic acid (4), (3β,22E)-estigmasta-5,22-dien-3-yl β-D-glucopyranoside (2), (2S) naringenin 7-O-β-glucopyranoside (prunin, 5), pinitol (6) and sucrose (7) were isolated and characterized. Furthermore, hexanic and chloroformic extracts were analyzed by GC-FID and GC-MS and 18 methylated fatty acids were identified for each extract in addition to three sterols. The methanolic and aqueous extracts were analyzed separately by HPLC-Q-TOF-MS, and 15 compounds were identified in each extract. The compounds 1, 2, and 7, in addition to 13 fatty acids and eight phenolic compounds, were identified for the first time in A. farnesiana. The extracts showed antitubercular (MIC 100-200 µg/mL) and antidysentery activity (MIC 100-200 µg/mL). Methyl gallate and its acetylated derivative showed activity against the sensible strain M. tuberculosis H37Rv with MIC values of 50-25 µg/mL, respectively. The flavanone prunin showed activity against multidrug resistant M. tuberculosis G122 (MIC 50 μg/mL). Methyl gallate, gallic acid and prunin showed activity against C. jejuni (MIC 50 μg/mL). The activity of tested extracts and isolated compounds against M. tuberculosis and dysentery bacteria justifies the ethnomedical use of A. farnesiana fruits for the treatment of tuberculosis and dysentery.
The dichloromethane extract of the roots of Jatropha dioica afforded riolozatrione (1) and a C-6 ... more The dichloromethane extract of the roots of Jatropha dioica afforded riolozatrione (1) and a C-6 epimer of riolozatrione, 6-epi-riolozatrione (2), as a new structure and only the second reported riolozane diterpenoid. The two known diterpenoids jatrophatrione (3) and citlalitrione (4) were also isolated and characterized. Both epimers 1 and 2 are genuine plant constituents, with 2 likely being the biosynthesis precursor of 1 due to the tendency for the quantitative transformation of 2 into 1 under base catalysis. The structural characterization and distinction of the stereoisomers utilized (1)H iterative full-spin analysis, yielding complete J-correlation maps that were represented as quantum interaction and linkage tables. The absolute configuration of compounds 1-4 was established by means of vibrational circular dichroism and via X-ray diffraction analysis for 1, 2, and 4. Additionally, the cytotoxic and antiherpetic in vitro activities of the isolates were evaluated.
Thirty-three meso-dihydroguaiaretic acid (meso-DGA) derivatives bearing esters, ethers, and amino... more Thirty-three meso-dihydroguaiaretic acid (meso-DGA) derivatives bearing esters, ethers, and amino-ethers were synthesized. All derivatives were tested against twelve drug-resistant clinical isolates of Gram-positive and Gram-negative bacteria, including sensitive (H37Rv) and multidrug-resistant Mycobacterium tuberculosis strains. Among the tested compounds, four esters (7, 11, 13, and 17), one ether (23), and three amino-ethers (30, 31, and 33) exhibited moderate activity against methicillin-resistant Staphylococcus aureus, whereas 30 and 31 showed better results than levofloxacin against vancomycin-resistant Enterococcus faecium. Additionally, nineteen meso-DGA derivatives displayed moderate to potent activity against M. tuberculosis H37Rv with minimum inhibitory concentration (MIC) values ranging from 3.125 to 50µg/mL. Seven meso-DGA derivatives bearing amino-ethers (26-31 and 33) exhibited the lowest MICs against M. tuberculosis H37Rv and G122 strains, with 31 being as potent as ...
Proceedings of The 20th International Electronic Conference on Synthetic Organic Chemistry, 2016
Riolozatrione is a natural diterpene isolated from Jatropha dioica to which antiherpetic activity... more Riolozatrione is a natural diterpene isolated from Jatropha dioica to which antiherpetic activity is attributed. Riolozatrione possess a unique diterpene core attractive for chemical modification. In this work, 5 new derivatives were obtained by chemical reduction and cyclopropane ring-opening. NMR techniques where used for the structural characterization. One and two-dimension NMR experiments (COSY, HMBC, HSQC, and NOE) confirm the structures of 5 new riolozatrione derivatives. Anti-herpetic activity was improved by chemical modification in some derivatives.
ABSTRACT Novel tetrahydroindeno[1,2-b]pyrrolidines were conveniently prepared in moderate to good... more ABSTRACT Novel tetrahydroindeno[1,2-b]pyrrolidines were conveniently prepared in moderate to good yields via a sequential Ugi multicomponent reaction or Staudinger/aza-Wittig/Ugi combination, followed by the palladium-catalyzed aerobic oxidative cyclization of the resulting Ugi adducts. GRAPHICAL ABSTRACT
El herpes es una enfermedad emergente, causada por la infección del virus herpes simplex tipo 1 (... more El herpes es una enfermedad emergente, causada por la infección del virus herpes simplex tipo 1 (VHS-1) y tipo 2 (VHS-2) en células de tejido mucoso. Aunque actualmente existen medicamentos para tratar esta enfermedad, se ha observado una emergente aparición de cepas resistentes en pacientes inmunocomprometidos, denotando la importancia de descubrir nuevos compuestos con actividad antiherpética. En México, es amplio el conocimiento de plantas medicinales, estas plantas son conocidas por ser fuente de nuevos medicamentos con actividades terapéuticas como la antiherpética 1. Dentro de estas plantas Juglans mollis, Persea americana, Hamelia patens, Salvia texana, Salvia ballotaeflora y Ceanothus coeruleus se encuentran en el noreste de México. MATERIALES Y MÉTODOS:
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