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1.
Chem Biodivers ; 18(12): e2100557, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34643999

RESUMEN

Murraya koenigii (L.) Spreng (Curry leaf) is a commercially important medicinal plant in South Asia, containing therapeutically valuable carbazole alkaloids (CAs). Thus, the quantitative evaluation of these compounds from different climatic zones of India are an important aspect for quality assessment and economic isolation of targeted compounds from the plant. In this study, quantitative estimation of CAs among 34 Indian natural populations of M. koenigii was assessed using UPLC/MS/MS. The collected populations represent the humid subtropical, tropical wet & dry, tropical wet, semi-arid, arid, and montane climatic zones of India. A total of 11 CAs viz. koenine-I, murrayamine A, koenigine, koenimbidine, koenimbine, O-methylmurrayamine A, girinimbine, mahanine, 8,8''-biskoenigine, isomahanimbine, and mahanimbine were quantified using multiple reaction monitoring (MRM) experiments within 5.0 min. The respective range for natural abundance of CAs were observed as 0.097-1.222, 0.092-5.014, 0.034-0.661, 0.010-1.673, 0.013-7.336, 0.010-0.310, 0.010-0.114, 0.049-5.288, 0.031-1.731, 0.491-3.791, and 0.492-5.399 mg/g in leaves of M. koenigii. The developed method shown linearity regression coefficient (r2 >0.9995), LOD (0.003-0.248 ng/mL), LOQ (0.009-0.754 ng/mL), and the recovery was between 88.803-103.729 %. The bulk of these CAs were recorded in their highest concentrations in the humid subtropical zone, followed by the tropical wet & dry zones of India. Further, principal component analysis (PCA) was performed which differentiated the climatic zones according to the dominant and significant CAs contents within the populations. The study concludes that the method established is simple, rapid, with high sample throughput, and can be used as a tool for commercial purposes and quality control of M. koenigii.


Asunto(s)
Alcaloides/análisis , Carbazoles/análisis , Murraya/química , Análisis de Componente Principal , Cromatografía Líquida de Alta Presión , India , Estructura Molecular , Espectrometría de Masas en Tándem
2.
Rapid Commun Mass Spectrom ; 32(4): 319-332, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-29178152

RESUMEN

RATIONALE: Catharanthus roseus is a well-known dicotyledonous medicinal plant containing diverse classes of bioactive terpene indole alkaloids (TIAs), in particular the anticancer agents vinblastine and vincristine. In view of the commercial importance of these compounds there is an urgent need to develop an accurate and reliable method for the screening of TIAs from C. roseus. METHODS: A method for the separation and characterization of these compounds was developed using high-performance liquid chromatography coupled with positive electrospray ionization quadrupole time-of-flight tandem mass spectrometry (HPLC/ESI-QTOF-MS/MS). Chromatographic separation of TIAs was carried out using a Thermo Betasil C8 column (250 mm × 4.5 mm, 5 µm) at 25°C using 0.1% formic acid in water and acetonitrile. RESULTS: Diagnostic fragmentation pathways for vinpocetine, vindesine, catharanthine, vinblastine, vindoline and vincristine were established on the basis of their product ions. A total of 72 TIAs were detected of which 11 were unambiguously identified by comparison with their standards, and the remaining 61 were tentatively identified. The geographical distribution of the TIAs in ethanolic extracts of 30 samples of C. roseus collected from five states of India was studied using principal component analysis (PCA). CONCLUSIONS: The developed analytical method together with diagnostic fragment patterns were used to rapidly and effectively identify targeted and untargeted TIAs in C. roseus. A PCA study of the results obtained was used to discriminate among the C. roseus samples.


Asunto(s)
Catharanthus/química , Catharanthus/clasificación , Cromatografía Líquida de Alta Presión/métodos , Extractos Vegetales/química , Alcaloides de Triptamina Secologanina/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Geografía , India , Análisis de Componente Principal , Alcaloides de Triptamina Secologanina/química , Alcaloides de Triptamina Secologanina/aislamiento & purificación , Espectrometría de Masas en Tándem/métodos
3.
J Sep Sci ; 40(17): 3422-3429, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28683189

RESUMEN

Phyllanthus species are extensively used in traditional medicines for the treatment of hepatic diseases due to their bioactive hypophyllanthin and phyllanthin. This work describes the development and validation of an ultra high performance liquid chromatography with tandem mass spectrometry method in polarity switching multiple reaction monitoring mode for the simultaneous detection and quantitation of 23 compounds using ultra-performance liquid chromatography coupled with electrospray-hybrid triple quadrupole-linear ion trap mass spectrometer. The validated parameters showed good linearity (R2  ≥ 0.996), limit of detection (0.05-1.62 ng/mL), limit of quantitation (0.15-4.95 ng/mL), precisions (intra-day: RSD ≤ 2.11%), (inter-day: RSD ≤ 2.91%), stability (RSD ≤ 2.56%) and overall recovery (98.22-104.48%; RSD ≤ 2.93%). The validated method was successfully applied in ethanolic extracts of P. amarus, P. niruri, P. emblica, P. fraternus, fractions of P. amarus and their herbal formulations for quantitation. The maximum content of hypophyllanthin (29.40 mg/g) and phyllanthin (56.60 mg/g) was detected in ethyl acetate fraction of P. amarus. The total content of 23 compounds was abundant in the ethanolic extract of P. emblica fruit. Principal component analysis was used to differentiate the selected Phyllanthus species and their herbal formulations. The results indicated that the present method could be used for quality control of Phyllanthus species and its herbal formulations.


Asunto(s)
Cromatografía Líquida de Alta Presión , Phyllanthus/química , Fitoquímicos/análisis , Preparaciones de Plantas/análisis , Espectrometría de Masas en Tándem , Frutas/química , Análisis de Componente Principal
4.
Biomed Chromatogr ; 31(3)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27565948

RESUMEN

Adhatoda beddomei and Adhatoda vasica leaf, known as 'Vasaka' and/or 'Vasa' in Ayurveda and 'Malabar nut' in English, is an official drug in the Indian Pharmacopoeia. The medicinal properties of these plants are due to the presence of pyrroquinazoline alkaloids. An UHPLC-ESI/MS/MS method in both positive and negative electrospray ionization in multiple-reaction-monitoring mode was developed and validated for the estimation of alkaloids and flavonoids in Adhatoda species and their marketed herbal formulations. Chromatographic separation was achieved on an Acquity UPLC® BEH C18 -column using a gradient elution with 0.1% formic acid in water and methanol. The developed method was validated as per International Conference on Harmonization guidelines and found to be accurate with overall recovery in the range 94.2-105.0% (RSD ≤ 1.71%), precise (RSD ≤ 3.44%) and linear (R2 ≥ 0.9992) over the concentration range of 0.5-1000 ng/mL. The total content of alkaloids and flavonoids were highest in the chloroform and aqueous fraction of A. vasica leaf, respectively. The results indicated that the developed method was simple, rapid, sensitive, selective and accurate for the estimation of multiple bioactive constituents in crude mixture, and therefore could make a contribution to the quality control of Adhatoda species and its derived herbal formulations.


Asunto(s)
Alcaloides/análisis , Cromatografía Líquida de Alta Presión/métodos , Flavonoides/análisis , Género Justicia/química , Espectrometría de Masas en Tándem/métodos
5.
Natl Med J India ; 30(1): 15-20, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28731001

RESUMEN

BACKGROUND: We aimed to generate evidence on the social and economic impact of out-of-pocket expenses incurred by households on illness. METHODS: We did a hospital-based cross-sectional study including a convenience sample of 374 inpatients and outpatients. RESULTS: The median illness expenditure was the same (₹62 500) for inpatients and outpatients. Of all respondents, 51.3% among the rural and 65.5% among the urban patients were employed before illness, but after illness only 24.4% among the rural and 23.4% among the urban patients remained in employment. The proportion of rural households of different socioeconomic categories that experienced decrease in expenditure on food, education and health, and those who had to sell land or cattle, and the education of whose children suffered was statistically significant. The proportion of indebted families in different socioeconomic classes was also statistically significant among both rural and urban patients. The lowest socioeconomic strata depended mostly upon the financial support of their friends to tide over the financial crisis of an illness. CONCLUSION: Our study shows that out-of-pocket expenses on healthcare are a burden not only for the poor but also the middle classes.


Asunto(s)
Gastos en Salud/estadística & datos numéricos , Hospitales Públicos/estadística & datos numéricos , Población Rural/estadística & datos numéricos , Factores Socioeconómicos , Población Urbana/estadística & datos numéricos , Adulto , Estudios Transversales , Composición Familiar , Femenino , Hospitales Públicos/economía , Humanos , India , Masculino , Persona de Mediana Edad , Centros de Atención Secundaria/estadística & datos numéricos , Centros de Atención Terciaria/estadística & datos numéricos , Adulto Joven
6.
Natl Med J India ; 30(6): 348-351, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30117451

RESUMEN

This study examined the effect of out-of-pocket expenditure of patients on their illness and other household changes impacting on their well-being, and assessed the socioeconomic status and below poverty line (BPL) card status among patients at the All India Institute of Medical Sciences, New Delhi. We did a hospital-based cross-sectional study of 374 inpatients and outpatients. Among the 374 study subjects, more than 69% of poor did not possess a BPL card. On the other hand, 5.5% of the above poverty line patients among the respondents possessed a BPL card. Of those having BPL cards, 84.4% belonged either to the lower middle, upper lower and lower socioeconomic status categories. Our data suggest that the inaccuracies in providing BPL cards limit access of the genuine poor to healthcare. In the light of national-level surveys on accessing healthcare and out-of-pocket expenditure by patients there is a case against 'targeting' in the delivery of public health services and user charges have an adverse impact on access to healthcare by the poor.


Asunto(s)
Equidad en Salud/economía , Gastos en Salud/estadística & datos numéricos , Renta/estadística & datos numéricos , Programas Nacionales de Salud/economía , Pobreza , Estudios Transversales , Femenino , Encuestas de Atención de la Salud/estadística & datos numéricos , Equidad en Salud/estadística & datos numéricos , Humanos , India , Masculino , Programas Nacionales de Salud/estadística & datos numéricos
7.
Phytochem Anal ; 28(4): 277-288, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28111813

RESUMEN

INTRODUCTION: Tinospora cordifolia is a widely distributed medicinal plant used in various traditional and commercial Ayurvedic formulations. Due to the wide use of this plant it is important to know the extent of variability in the metabolite profile resulting from geographical location, season and gender. OBJECTIVE: To develop a statistical approach based on phytochemical markers for confident prediction of variations in metabolic profile and cytotoxicity due to geographical, seasonal and gender difference in T. cordifolia stem. METHODS: A HPLC-ESI-QTOF-MS method was used for the metabolite profiling of T. cordifolia stem. The data were analysed using chemometric methods including Student's t-test, ANOVA, FA/PCA and ROC curve analysis and validated for the identification of chemical variations. The bioactivity of selected samples was also tested using a cell cytotoxicity assay to assess the functional aspect of the phytochemical variability. RESULTS: The chemometric approach applied here identified marker ions for geographical locations (m/z 294.1139 and 445.2136), seasons (m/z 344.1482, 359.1501, and 373.1305) and gender (m/z 257.1380) with 100% statistical sensitivity and specificity. An in vitro cytotoxicity evaluation revealed that male T. cordifolia stem was the most effective in inhibiting the growth of cancerous cell lines. CONCLUSIONS: The developed and validated chemometric approach identified the analytical markers for phytochemical variations in unknown T. cordifolia stem samples from male or female plants and samples collected from different geographical locations and seasons. The results are supported by comparative cytotoxic activity data. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Fitoquímicos/análisis , Extractos Vegetales/análisis , Tallos de la Planta/química , Estaciones del Año , Tinospora/química , Cromatografía Líquida de Alta Presión , Geografía , Espectrometría de Masas , Metaboloma , Plantas Medicinales/química
8.
Phytochem Anal ; 27(5): 296-303, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27437669

RESUMEN

INTRODUCTION: Rauvolfia serpentina is an endangered plant species due to its over-exploitation. It has highly commercial and economic importance due to the presence of bioactive monoterpene indole alkaloids (MIAs) such as ajmaline, yohimbine, ajmalicine, serpentine and reserpine. OBJECTIVE: To develop a validated, rapid, sensitive and selective ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole-linear ion trap mass spectrometry (UHPLC-QqQLIT -MS/MS) method in the multiple reaction monitoring (MRM) mode for simultaneous determination of bioactive MIAs in ethanolic extract of seven Rauvolfia species and herbal formulations. METHODS: The separation of MIAs was achieved on an ACQUITY UPLC BEH™ C18 column (1.7 µm, 2.1 mm × 50 mm) using a gradient mobile phase (0.1% aqueous formic acid and acetonitrile) at flow rate 0.3 µL/min in 7 min. The validated method showed good linearity (r(2)  ≥ 0.9999), limit of detection (LOD) (0.06-0.15 ng/mL), limit of quantitation (LOQ) (0.18-0.44 ng/mL), precisions [intraday: relative standard deviation (RSD) ≤ 2.24%, interday: RSD ≤ 2.74%], stability (RSD ≤ 1.53%) and overall recovery (RSD ≤ 2.23%). RESULTS: The validated method was applied to quantitate MIAs. Root of Rauvolfia vomitoria showed a high content of ajmaline (48.43 mg/g), serpentine (87.77 mg/g) whereas high quantities of yohimbine (100.21 mg/g) and ajmalicine (120.51 mg/g) were detected in R. tetraphylla. High content of reserpine was detected in R. micrantha (35.18 mg/g) and R. serpentina (32.38 mg/g). CONCLUSION: The encouraging results of this study may lead to easy selection of suitable Rauvolfia species according to the abundance of MIAs. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Alcaloides Indólicos/análisis , Espectrometría de Masas/métodos , Monoterpenos/análisis , Extractos Vegetales/química , Rauwolfia/química , Etanol/química , Límite de Detección , Análisis de Componente Principal , Reproducibilidad de los Resultados
9.
Phytochem Anal ; 27(2): 92-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26627195

RESUMEN

INTRODUCTION: The stem of dioecious Tinospora cordifolia (Menispermaceae) is a commonly used traditional Ayurvedic medicine in India having several therapeutic properties. OBJECTIVE: To develop and validate LC-MS methods for the identification and simultaneous quantitation of various secondary metabolites and to study metabolomic variations in the stem of male and female plants. METHODS: Ethanolic extract of stems were analysed by HPLC/ESI-QTOF-MS/MS for rapid screening of bioactive phytochemicals. High resolution MS and MS/MS in positive ESI mode were used for structural investigation of secondary metabolites. An UPLC/ESI-QqQ(LIT) -MS/MS method in MRM mode was developed and validated for the simultaneous quantitation of five bioactive alkaloids. RESULTS: Identification and characterisation of 36 metabolites including alkaloids, sesquiterpenes and phytoecdysteroids were performed using LC-MS and MS/MS techniques. The bioactive alkaloids such as jatrorrhizine, magnoflorine, isocorydine, palmatine and tetrahydropalmatine were successfully quantified in male and female plants. The mean abundances of magnoflorine jatrorrhizine, and oblongine were significantly (P < 0.05) higher in male plants while mean abundances of tetrahydropalmatine, norcoclaurine, and reticuline were significantly (P < 0.05) higher in female plants. CONCLUSIONS: Phytochemicals in the stem of male and female Tinospora cordifolia showed significant qualitative and quantitative variations. LC-MS and MS/MS methods can be used to differentiate between male and female plants based on their chemical profiles and quantities of the marker bioactive alkaloids. This chemical composition difference was also evident during vegetative stage when there were no male and female flowers.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Fitoquímicos/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Tinospora/química , Alcaloides/análisis , Ecdisterona/análisis , Estándares de Referencia , Reproducibilidad de los Resultados , Sesquiterpenos/análisis
10.
Rapid Commun Mass Spectrom ; 29(12): 1095-106, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-25981540

RESUMEN

RATIONALE: Adhatoda vasica Nees is a well-known Ayurvedic medicinal plant, belonging to the family Acanthaceae. This study aims to seek identification and characterization of flavonoid C- and O-glycosides in the aqueous fraction of the plant leaves. METHODS: A method was developed for simultaneous characterization of flavonoids and their glycosides using high-pressure liquid chromatography with quadrupole time-of-flight mass spectrometry (HPLC/ESI-QTOF-MS/MS). The chromatographic separation was carried on an Agilent Poroshell 120 EC-C18 column (4.6 × 150 mm, 2.7 µm) operated with 0.1% formic acid aqueous solution and methanol as the mobile phase. RESULTS: The fragmentations of the studied [M-H](-) ions of C-glycosides were shown to be cross-ring cleavages of the glycoside moiety [M-H-(60/90/120)](-) whereas O-glycosides were shown to eliminate the sugar moiety (Y0 (-) or [Y0 -H](-) ) from the aglycone unit; 6-C-glycosides exhibited [M-H-18](-) , a characteristic ion, and also a higher abundance of (0,3) X6 or 8 ions in comparison to 8-C glycosides; flavonoid 6,8-di-C-glycosides exhibited cross-ring cleavages of the sugar attached to the C-6 position preferentially. CONCLUSIONS: This method was successfully applied for analysis of flavonoids and their glycosides in Adhatoda vasica leaves. A total of 29 compounds were tentatively identified including 17 C-, nine O-glycosides and three flavonoids.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Flavonoides/análisis , Glicósidos/análisis , Género Justicia/química , Espectrometría de Masas en Tándem/métodos , Flavonoides/química , Glicósidos/química , Hojas de la Planta/química , Plantas Medicinales , Espectrometría de Masa por Ionización de Electrospray/métodos
11.
J Sep Sci ; 38(12): 2007-13, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25847792

RESUMEN

Berberis species are well known and used extensively as medicinal plants in traditional medicine. They have many medicinal values attributable to the presence of alkaloids having different pharmacological activities. In this study, a method was developed and validated as per international conference on harmonization guidelines using ultra high performance liquid chromatography with hybrid triple quadrupole-linear ion trap mass spectrometry operated in the multiple reaction monitoring mode for nine bioactive compounds, including protoberberine alkaloids, aporphine alkaloids and chlorogenic acid. This method was applied in different plant parts of eight Berberis species to determine variations in content of nine bioactive compounds. The separation was achieved on an ACQUITY UPLC CSH™ C18 column using a gradient mobile phase at flow rate 0.3 mL/min. Calibration curves for all the nine analytes provided optimum linear detector response (with R(2) ≥0.9989) over the concentration range of 0.5-1000 ng/mL. The precision and accuracy were within RSDs ≤2.4 and ≤2.3%, respectively. The results indicated significant variation in the total contents of the nine compounds in Berberis species.


Asunto(s)
Alcaloides/química , Berberis/química , Cromatografía Líquida de Alta Presión/métodos , Isoquinolinas/química , Aporfinas/química , Berberina/química , Ácido Clorogénico/análisis , Flores/química , Límite de Detección , Modelos Lineales , Extractos Vegetales/química , Hojas de la Planta/química , Raíces de Plantas/química , Tallos de la Planta/química , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
12.
Nat Prod Res ; 37(14): 2461-2465, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35285353

RESUMEN

Chamaecostus cuspidatus (Nees & Mart.) C.D.Specht & D.W.Stev and Cheilocostus speciosus (J.Koenig) C.D.Specht contain bioactive compounds that possess many pharmacological activities including antidiabetic and hypolipidemic. These plants are used to treat diabetes by herbal healers. Considering the traditional use of C. cuspidatus and C. speciosus, the present study is designed to perform qualitative and quantitative analysis as well as in-vitro anti-adipogenesis against 3T3-L1 cells to ensure efficacy. A total of thirty-eight compounds were identified using HPLC-QTOF-MS/MS. Quantification of ten bioactive compounds among identified compounds was performed by UPLC-QqQLIT-MS/MS. The quantification method was validated according to ICH guidelines (International conference on harmonization guidelines). Quantification of bioactive compounds of different organs of C. cuspidatus and C. speciosus showed remarkable differences in the content. Microscopic and ORO absorbance confirmed the antiadipogenic potential of leaves (L-02), roots (R-02) of C. cuspidatus and leaves of C. speciosus (L-01) in 3T3-L1 cells.


Asunto(s)
Extractos Vegetales , Espectrometría de Masas en Tándem , Cromatografía Liquida , Espectrometría de Masas en Tándem/métodos , Extractos Vegetales/química , Cromatografía Líquida de Alta Presión/métodos , Fitoquímicos/análisis
13.
J Org Chem ; 77(3): 1414-21, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22272987

RESUMEN

Several diversity-oriented syntheses of N-fused polycyclic heterocycles have been demonstrated but most of them are based on point diversity within the same library and usually involve time-consuming sequential multistep syntheses, which also suffer from low yields and/or poor precursor scopes. We have developed a new strategy for the syntheses of skeletal diverse N-fused polycyclic compounds via an Ugi-type MCR followed by a CuI-catalyzed coupling reaction or tandem Pictet-Spengler reaction. This two-step sequence provides eight distinct skeleton of fused {6-5-5-6}, {5-5-5-6}, {6-5-6-6}, and {5-5-6-6} ring systems that have applications in medicinal chemistry and chemical genetics too.


Asunto(s)
Técnicas de Química Sintética/métodos , Cobre/química , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/síntesis química , Yoduros/química , Compuestos Policíclicos/química , Compuestos Policíclicos/síntesis química , Aldehídos/química , Catálisis
14.
Org Biomol Chem ; 10(25): 4977-86, 2012 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-22614030

RESUMEN

The synthesis of three new classes of heteroarenes, built through the sequential fusion of naphthalene, benzo/naphtho[b]oxepine and thiochromene rings with pyran and pyrimidine ring systems to give 'U and Z' shaped structural frameworks is reported. The methodology is based on the synthesis of pyran fused intermediates, 1-methylthio-3-oxo-5,6-dihydro-3H-benzo[f]chromene-2-carbonitrile (3), 4-methylthio-2-oxo-5,6-dihydro-2H-benzo/naphtho[b]pyrano[2,3-d]oxepine-3-carbonitriles (10, 20) and 4-methylthio-2-oxo-2,5-dihydrothiochromeno[4,3-b]pyran-3-carbonitriles (15) from the reaction of 2-tetralone, benzo/naphtho[b]oxepin-5-ones and thiochromen-4-ones with methyl 2-cyano-3,3-dimethylthioacrylate respectively. Further condensation of intermediates 3, 10, 20 and 15 with amidines led to the formation of tetracyclic 'U' shaped 4-amino-2-aryl-7,8-dihydro-5-oxo-5H-naphtho[2,1-b]pyrimido[4,5-d]pyrans (8) and 'Z' shaped 4-amino-2-aryl-5-oxo-12,13-dihydro-5H-benzo/naphtho[b]oxepino[5,4-b]pyrimido[4,5-d]pyrans (12, 22) and 4-amino-2-aryl-5-oxo-5,12-dihydrothiochromeno[4,3-b]pyrimido[4,5-d]pyrans (17). Compound 12f forms a chain of dimers through N-HO interactions as indicated by the X-ray structure analysis, and the quantum chemical calculations performed at the MP2 level indicate that this interaction energy is 10 kJ mol(-1).


Asunto(s)
Compuestos Policíclicos/síntesis química , Modelos Moleculares , Estructura Molecular
15.
Indian J Public Health ; 56(2): 133-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22910622

RESUMEN

Conquering disease and ill health has been an age old pursuit of man. The scientific and technological revolution of the last century ushered in major and important advances in preventive and curative medical technology which fired a new hope in the fight against communicable diseases. However, the experience over centuries shows that major decline in communicable diseases began much before the advent of modern technology due to advances in the socio-economic and environmental conditions of the people. There has been an attempt by the multilateral and unilateral agencies to supplant the expedient of technological interventions like vaccination campaigns as a substitute to socio-economic advancement in the third world countries. The dividends of this approach have been equivocal and have had an effect of distorting public health priorities in the third world. There seems to be an obsession with technology among the policy planners - a phenomenon that we call as techno-centrism; the latest example of which is the pulse polio campaign. This paper draws upon an epidemiological approach to vaccination programs as a tool to unravel this phenomenon.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Enfermedades Transmisibles/epidemiología , Política de Salud , Vacunación , Países en Desarrollo , Humanos , India/epidemiología
16.
J Org Chem ; 76(21): 8930-43, 2011 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-21955144

RESUMEN

The development of an innovative method to access enantiopure 2,4-disubstituted 6-hydroxy-1,6-dihydro-2H-pyridin-3-ones starting from D-glucal via the aza-Achmatowicz transformation has been described. These highly functionalized pyridin-3-ones have been utilized for the synthesis of contiguously substituted pyridines through a rapid and efficient Et(3)N/Ac(2)O promoted cyclo-elimination, aromatization cascade, allowing the facile assembly of important pyridine-based building blocks like 2-substituted 3-acetoxy-4-iodopyridines and enantiopure 2-substituted 3-acetoxy-4-pyridinemethanols possessing benzylic stereogenic centers, whose synthesis otherwise would be tedious. The utilization of commercially available sugars as starting materials, mild reaction conditions, catalytic transfer hydrogen (CTH) of α-furfuryl azide derivatives, transfer of chiral aryl/alkyl methanols from enulosides to pyridin-3-ones and pyridines, high yields, and short reaction times are key features of this method. The utility of the method has been further exemplified by demonstrating the usage of the 2-substituted 3-acetoxy-4-iodopyridine for the construction of biologically significant molecules like 2,7-disubstituted furo[2,3-c]pyridines and 7,7'-disubstituted 2,2'-bifuro[2,3-c]pyridines.


Asunto(s)
Yodopiridonas/química , Yodopiridonas/síntesis química , Piridinas/química , Piridinas/síntesis química , Piridonas/química , Piridonas/síntesis química , Estructura Molecular , Estereoisomerismo
17.
J Org Chem ; 76(18): 7474-81, 2011 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-21806032

RESUMEN

A new series of thermally stable blue light-emitting nonplanar pyrenylarenes having an amine donor and a nitrile acceptor group was prepared from a ketene-S,S-acetal under conventional heating and/or microwave irradiation. The photophysical, electrochemical, and optical behavior of donor-acceptor pyrenylarenes are demonstrated. The performance of blue light-emitting pyrenylarenes was investigated by fabricating a multilayer device with the device configuration of ITO/PEDOT:PSS (40 nm)/NPB (30 nm)/pyrenylarene (55 nm)/BCP (8 nm)/LiF (0.6 nm)/Al (200 nm), which exhibited low turn-on voltage (5 V) with luminance efficiency of 0.8 Cd/A with nonaggregation behavior in both solution and solid state.


Asunto(s)
Hidrocarburos/química , Luz
18.
J Ethnopharmacol ; 275: 114054, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33831465

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Andrographis paniculata (Burm.f.) Nees is a medicinal herb of the Asian countries used in many traditional medicinal systems for the treatment of diarrhea, flu, leprosy, leptospirosis, malaria, rabies, upper respiratory infections, sinusitis, syphilis, tuberculosis and HIV/AIDS etc. AIM OF THE STUDY: This review aims to provide the comprehensive, accurate and authentic information on traditional uses, phytochemistry and pharmacological properties of various extracts/fractions as well as phytocostituents of A. paniculata. In addition, this review also aims to provide advance and sensitive analytical methods along with chemical markers used in the standardization of herbal products for quality control (QC)/quality assurance (QA). MATERIALS AND METHODS: All relevant publications were considered within the years 1983-2020. The publications were searched from Google Scholar, PubChem, Chemspider, PubMed, Elsevier, Wiley, Web of Science, China Knowledge Resource Integrated databases and ResearchGate using a combination of various relevant keywords. Besides, relevant published books and chapters were also considered those providing an overview of extant secondary literature related to traditional knowledge, phytochemistry, pharmacology and toxicity of the plant. RESULTS AND DISCUSSION: In this review, 344 compounds, including, terpenoid lactones, flavonoids, phenolic acids, triterpenes and volatile compounds were summarized out of which more than half of the compounds have no reported pharmacological activities yet. Terpenoid lactones and flavonoids are the major bioactive classes of compounds of A. paniculata which are responsible for pharmacological activities such as anticancer and antioxidant activities, respectively. Biosynthetic pathways and active sites for target proteins of both terpenoid lactones and flavonoids were considered. Analgesic, anticancer, antidiabetic, antifertility, antiinflammatory, antimalarial, antimicrobial, antioxidant, antipyretic, antiviral, antiretroviral, antivenom, cardioprotective, hepatoprotective, immunomodulatory and neuroprotective activities have been also reported. Andrographolide is a major characteristic active principle and responsible for most of the pharmacological activities. Therefore, andrographolide has been selected as a marker for the standardization of raw and marketed herbal products by TLC, HPTLC, HPLC, GC-MS, HPLC-MS and HPLC-MS/MS methods for QC/QA. CONCLUSIONS: Conclusive evidence showed that the pharmacological activities reported in crude extracts and chemical markers are supporting and provides confidence in the traditional use of A. paniculata as a herbal medicine. The andrographolide could be used as a chemical marker for the QC/QA of raw and A. paniculata derived herbal products. Lactone ring in terpenoid lactone is an active site for targeted proteins. More efforts should be focused on the identification of the chemical markers from A. paniculata to provide a practical basis for QC/QA. Several aspects such as the mechanism of therapeutic potential, molecular docking technology and multi-target network pharmacology are very important for drug discovery and needed more investigation and should be considered. This compilation may be helpful in further study and QC/QA.


Asunto(s)
Andrographis/química , Fitoquímicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Control de Calidad , Animales , Asia , Humanos , Medicina Tradicional , Fitoquímicos/biosíntesis , Fitoquímicos/uso terapéutico , Fitoquímicos/toxicidad , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad
19.
J Pharm Biomed Anal ; 193: 113707, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-33160219

RESUMEN

Ultra Performance Liquid Chromatography coupled with hybrid triple quadrupole linear ion trap tandem mass spectrometry (UPLC-ESI-QqQLIT-MS/MS) method in multiple reaction monitoring (MRM) acquisition mode was developed and validated for identification and simultaneous determination of potential anti-diabetic and anti-malarial compounds in ethanolic extracts of different Artemisia species. The chromatographic separation was carried out on an Acquity BEH™ C18 column (1.7 µm, 2.1 × 50 mm) with 0.1 % (v/v) formic acid in water and acetonitrile as mobile phase under gradient condition in 6 min. The developed method was validated in terms of linearity, LOD, LOQ, precision, stability and recovery according to international conference on harmonization guidelines. The correlation coefficients of all the calibration curves were ≥0.9902 and recoveries ranged from 98.22 to 104.49% (RSD ≤2.18 %). Relative standard deviations of intra-day, inter-day precisions and stability were ≤ 1.04, 1.09 and 2.80 %, respectively. The quantitative results showed remarkable differences in the content of all the compounds in different Artemisia species. The quantitative values of each peak were summarized as mean ± SD. The statistical analysis for comparison of observed quantitative differences of each compound was done to show that they are statistically significant. In-vitro assessment of extracts of selected Artemisia species inhibited adipocyte differentiation in 3T3-L1 cells, hence it may have certain phytochemicals which are responsible for reducing obesity and related metabolic disorders.


Asunto(s)
Artemisia , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Extractos Vegetales , Reproducibilidad de los Resultados
20.
Biomed Chromatogr ; 24(12): 1283-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21077247

RESUMEN

Piper betle Linn. is a traditional plant associated with the Asian and southeast Asian cultures. Its use is also recorded in folk medicines in these regions. Several of its medicinal properties have recently been proven. Phytochemical analysis showed the presence of mainly terpenes and phenols in betel leaves. These constituents vary in the different cultivars of Piper betle. In this paper we have attempted to profile eight locally available betel cultivars using the recently developed mass spectral ionization technique of direct analysis in real time (DART). Principal component analysis has also been employed to analyze the DART MS data of these betel cultivars. The results show that the cultivars of Piper betle could be differentiated using DART MS data.


Asunto(s)
Espectrometría de Masas/métodos , Piper betle/química , Extractos Vegetales/análisis
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