Countercurrent Chromatography
Mostrando 1-12 de 23 artigos, teses e dissertações.
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1. HSCCC Separations of Rutin Esters Obtained by Enzymatic Reaction Catalyzed by Lipase
The flavonoid rutin presents several pharmacological effects, despite this, its application in the pharmaceutical industry can be significantly limited by its low bioavailability. The development of lipophilic derivatives by esterification of hydroxyl groups with fatty acid chains may be an effective strategy to change their physicochemical properties. This
J. Braz. Chem. Soc.. Publicado em: 2021-03
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2. Unexpected Rearrangement and Aromatization on Dehydration Reaction of the Bioactive Diterpenequinone 7α-Hydroxyroyleanone
7a-Hydroxyroyleanone is a bioactive diterpene isolated from leaves of Tetradenia riparia, active against tuberculosis and T. cruzi. In order to use this compound as starting material for the synthesis of compounds with enhanced bioactivity we aimed the dehydration of the 7-alpha-hydroxyl group of royleanone. The reaction performed in acetic acid and hydrochl
J. Braz. Chem. Soc.. Publicado em: 2020-03
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3. A New Tetraglycosylated Flavonoid from Leaves of Platycyamus regnellii Benth. Isolated by High-Speed Countercurrent Chromatography
A new tetraglycosylated flavonoid derivative of kaempferol was isolated from the butanol extract of leaves of Platycyamus regnellii (Fabaceae) using high-speed countercurrent chromatography (HSCCC). The butanol extract (960.5 mg) was initially fractionated with the solvent system EtOAC-BuOH-H2O 2:8:10 (v/v/v) (elution in normal phase mode). The fractions con
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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4. Chemical Composition and Anti-Inflammatory Activity of the Decoction from Leaves of a Cultivated Specimen of Myracrodruon urundeuva
Myracrodruon urundeuva (Anacardiaceae) is the scientific designation of “aroeira-do-sertão”, a tree well dispersed at the northeastern Brazil. The medicinal use of this plant is widespread throughout the rural population and the inner trunk bark decoction is used to treat cutaneous affections, urinary and respiratory diseases, and gynecological problems
J. Braz. Chem. Soc.. Publicado em: 12/08/2019
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5. PREPARATIVE SEPARATION OF ISOQUINOLINE ALKALOIDS FROM PHELLODENDRI CORTEX BY PH-ZONE-REFINING COUNTER-CURRENT CHROMATOGRAPHY
pH-Zone-refining counter-current chromatography (PZRCCC) was successfully used for preparative separation isoquinoline alkaloids from Phellodendri Cortex. Two target compounds of berberine and palmatine were completely resolved by a two-phase solvent system chloroform/methanol/water (4:2:2, v/v), with 10 mmol L-1 HCl in upper stationary phase and 10 mmol L-1
Quím. Nova. Publicado em: 2018-03
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6. Isolation of quinoline alkaloids from three Choisya species by high-speed countercurrent chromatography and the determination of their antioxidant capacity
Abstract Choisya ternata Kunth, C. ternata var. sundance Kunth and the hybrid Choisya ‘Aztec-Pearl’ are three related species belonging to the Rutaceae family. Ethanol extracts were prepared from the leaves of these three species and evaluated in relation to their antioxidant activity using in vitro and ex vivo models. The ethanol extracts belonging to t
Rev. bras. farmacogn.. Publicado em: 2017-06
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7. Diterpenes and a new benzaldehyde from the mangrove plant Rhizophora mangle
ABSTRACT This work describes the isolation, by high-speed counter-current chromatography, of the diterpenes manool, jhanol and steviol and the benzaldehyde p-oxy-2-ethylhexyl benzaldehyde from the stilt roots hexane extract of the mangrove plant Rhizophora mangle L., Rhizophoraceae. For this, a non-aqueous biphasic solvent system composed of hexane–acetoni
Rev. bras. farmacogn.. Publicado em: 2017-04
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8. Separation and purification of three stilbenes from the radix of Polygonum cillinerve (Nakai) Ohwl by macroporous resin column chromatography combined with high-speed counter-current chromatography
An effective method for the rapid separation and purification of three stilbenes from the radix of Polygonum cillinerve (Nakai) Ohwl by macroporous resin column chromatography combined with high-speed counter-current chromatography (HSCCC) was successfully established. In the present study, a two-phase solvent system composed of chloroform-n-butanol-methanol
Quím. Nova. Publicado em: 2014
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9. Preparative separation of polyphenols from artichoke by polyamide column chromatography and high-speed counter-current chromatography
An efficient method for the rapid separation and purification of polyphenols from artichoke by polyamide column chromatography in combination with high-speed counter-current chromatography (HSCCC) was successfully built. The crude ethanol extracts from dry artichoke were first pre-separated by polyamide column chromatography and divided in two parts as sampl
Quím. Nova. Publicado em: 2013
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10. Preparative separation and purification of bufadienolides from ChanSu by high-speed counter-current chromatography combined with preparative HPLC
Eight bufadienolides were successfully isolated and purified from ChanSu by high-speed counter-current chromatography (HSCCC) combined with preparative HPLC (prep-HPLC). First, a stepwise elution mode of HSCCC with the solvent system composed of petroleum ether - ethyl acetate - methanol - water (4:6:4:6, 4:6:5:5, v/v) was employed and four bufadienolides, t
Quím. Nova. Publicado em: 2013
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11. Preparative separation of C19-diterpenoid alkaloids from Aconitum carmichaelii Debx by pH‑zone-refining counter-current chromatography
The technique of pH-zone-refining counter-current chromatography was successfully applied to preparatively separate three C19-diterpenoid alkaloids from the crude extracts of Aconitum carmichaelii for the first time using a two-phase solvent system of petroleum ether-ethyl acetate-methanol-water (5:5:1:9, v/v/v/v). Mesaconitine (I), hypaconitine (II), and de
Quím. Nova. Publicado em: 2013
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12. Purification of a synthetic pterocarpanquinone by countercurrent chromatography
A cromatografia contracorrente (CCC) foi empregada como uma alternativa útil, rápida e econômica às técnicas cromatográficas convencionais na purificação de uma pterocapanoquinona sintética, LQB 118. A separação foi feita em duas etapas utilizando o sistema de solvente hexano-clorofórmio-metanol-água 2:1,5:5:2 em ambas as etapas. A purificação
Journal of the Brazilian Chemical Society. Publicado em: 2012-06