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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pyrolytic and Photolytic Studies of 3- (o-Methoxy phenyl)-1-phenylprop-2-en-1-one and Its Derivatives

Chou, Chih-Tsung 29 July 2010 (has links)
Pyrolysis of 3- (o-methoxyphenyl)-1-phenylprop-2-en-1-one(49) ¡B1- (o-methoxyphenyl)-3-phenylprop-2-en-1-one (50) and 1-(o-methoxyphenyl)-3-phenylprop -2-yn-1-one (51) gave the expected cyclic products 2-phenylbenzo[b]furan (11) and flavone (73). Furthermore, compounds 49-51 gave phenanthrene-9,10-dione (71)¡Bfluoren-9-one (14) and others as the minor products at high temperture. Under photolytic condition, compounds 49-51 gave photocyclic product (73) all in low yields and recovered mostly the starting materials.
2

Phenolic Compounds of Sorghum, their Chemopreventive Properties and Absorption

Taleon Alban, Victor Manuel 16 December 2013 (has links)
Sorghum contains many phenolic compounds which have potential antioxidant, anti-inflammatory, and chemopreventive properties as well as natural colorants in foods. Phenolic compounds of stalks, sheaths, leaves, glumes and grains from tan (ARTx631/RTx436), red (Tx2911) and purple (Tx3362) sorghum plants were characterized by UPLC-MS/MS. Antiproliferative properties of selected sorghum extracts were evaluated using HT-29 colon cancer cells and absorption of their polyphenolics was determined by a Caco-2 in vitro model system. Phenolic acids, flavones, 3-deoxyanthocyanidins and chalcones were found in all plant components. Phenolic acids were predominant in the stalks, sheaths and grains of all sorghum types. Flavone glycosides were predominant in leaves, sheaths and stalks while flavone aglycones in glumes and grains. 3-Deoxyanthocyanidins and chalcones were mostly found in sheaths, leaves, glumes and grains of Tx2911 (red) and Tx3362 (purple) genotypes. Sorghum leaves showed high levels of flavone glycosides while glumes had high levels of flavones aglycones. Glume extract of ATx631/RTx436 (tan) and Tx2911 genotypes had the strongest antiproliferation activity (IC_(50) = 85-178 µg/ml), these extracts had also the highest levels of flavone aglycones (19.6-49.8 mg/g). Absorption of flavones (30.4-42.3 %) was higher than 3-deoxyantocyanidins (1.4-11.3%), while absorption of methoxylated 3-deoxyanthocyanidins (11.3%) was higher than non-methoxylated 3-deoxyanthocyanidins (1.4 – 1.6 %). Flavones had high absorption compared to other sorghum phenolics suggesting that sorghum flavone aglycones are more bioavailable than other sorghum phenolic compounds. Consequently, sorghum glumes could be used as used as a source of phytochemicals to increase value of sorghum crop.
3

Pharmacokinetics, Tissue Distribution, Synergistic Activity, and Antitumor Activity of Two Isomeric Flavones

Whitted, Crystal L 01 December 2016 (has links)
Flavonoids are polyphenolic secondary metabolites found in plants that have bioactive properties including antiviral, antioxidant, and anticancer. Two isomeric flavone were extracted from Gnaphalium elegans and Achyrocline bogotensis, plants used by the people from the Andean region of South America as remedies for cancer. 5,7-dihydroxy-3,6,8-trimethoxy-2-phenyl-4H-chromen-4-one (5, 7–dihydroxy- 3, 6, 8 trimethoxy flavone/ flavone A) and 3,5-dihydroxy-6,7,8-trimethoxy-2-phenyl-4H-chromen-4-one (3, 5–dihydroxy-6, 7, 8–trimethoxy flavone/ flavone B) have shown antineoplastic activity against colon cancer cell lines dependent upon their differentiation status. Pharmacokinetic studies reported herein were used to determine dosing for antitumor assays, as well as determine target tissue concentration. These included the development of methods to extract the flavones from plasma or colon tissue and reverse phase high performance liquid chromatography methods for quantification. Quantification methods were linear (r2 ≥ 0.99) with plasma calibration curves ranging from 250 - 2,500 ng/mL and 2,500 - 100,000 ng/mL for both flavones and colon calibration curves ranging from 250 – 100,000 ng/g (flavone A) and 1,000-25,000 ng/g (flavone B). Intravenous administration of a 20 mg/kg dose in rats yielded half-lives of 83.68 ± 56.61 and 107.45 ± 53.31 minutes with clearance values of 12.99 ± 13.78 and 80.79 ± 35.06 mL/min/kg for flavones A and B, respectively. Analysis of colon tissue yielded concentrations of 1639 ± 601 ng/g (flavone A) and 5975 ± 2480 ng/g (flavone B), suggesting both may be good candidate for individual or adjunct therapy for colon cancer due to distribution to the target tissue. Preliminary studies in colon cancer cells CaCo 2 and HCT 116 using either flavone in combination with 5-fluorouracil (5-FU) suggested synergistic activity of these compounds. The combination treatment increased induction of apoptosis by enhancing the DNA damaging mechanism of 5-FU. In vivo, preliminary xenograft experiments using HCT 116 cells showed smaller tumors in mice dosed with flavone B as compared to the 5-FU or combination treatment. Further experiments are warranted to confirm these observations.
4

Flavones substituées : une nouvelle classe de composés pour le traitement du paludisme : optimisation vers un candidat médicament / Substituted flavones : a new class of compounds to treat malaria : hit to lead optimization

Nardella, Flore 23 May 2017 (has links)
Le paludisme est responsable de plus de 438 000 morts en 2015. L’apparition et la propagation de P. falciparum résistants à l’artémisinine, l’antipaludique le plus puissant, est un problème majeur en Asie du Sud-Est. Un besoin impérieux de nouveaux médicaments présentant une action rapide et conservée vis-à-vis de ces parasites résistants se fait sentir pour remplacer l’artémisinine. Cette thèse porte sur le développement d’une nouvelle série chimique inspirée d’un biflavonoïde naturel, la lanaroflavone. Le composé tête-de-série MR27770 présente des propriétés intéressantes : il agit de façon plus rapide que l’artémisinine tout au long du cycle érythrocytaire du parasite, ses propriétés pharmacocinétiques sont prometteuses et il est partiellement actif chez la souris impaludée. De plus, il ne présente pas de résistances croisées avec l’artémisinine ou les autres antipaludiques. Son mécanisme d’action n’est pas connu mais pourrait impliquer un stress osmotique. Ce composé prometteur présente néanmoins une activité moyenne in vitro ce qui a motivé l’étude topologique de sa structure et mené à des dérivés optimisés. / Malaria was responsible for 438.000 deaths in 2015. The increasing proportion of P. falciparum parasites resistant to artemisinin, the most potent antimalarial, is a major concern in Southeast Asia. Fast acting drugs with unaltered activity versus the current multi-drug resistant strains are urgently needed to replace artemisinin. This thesis deals with a new antimalarial series based on the structure of an active natural biflavonoid called lanaroflavone. The lead compound, MR27770, displays interesting properties: it acts throughout the blood cycle faster than artemisinin, its pharmacokinetic properties are promising, and it exhibits a partial in vivo antimalarial activity. Plus, it has no cross-resistance with artemisinin or other antimalarials. Its mode of action is unknown and could imply an osmotic stress. This promising compound has however a mild in vitro activity which motivated the topological study of its structure and led to optimized derivatives.
5

Determinação da estrutura cristalina e molecular de uma flavona. / Determination of the crystalline structure and molecular of a flavone.

Souza Junior, Jaime de 24 May 1996 (has links)
Neste trabalho apresenta-se inicialmente algumas considerações sobre a difração de raios-X, suas principais leis, fatores de correção dos dados experimentais, uma revisão sobre os principais Métodos Diretos de resolução da estrutura, e considerações sobre o refinamento da estrutura obtida. A seguir descreve-se a determinação da estrutura cristalina do produto natural 5,4\'-Dihidroxi-3\', 5\' -dimetoxi- 6,7 -(2\",2\" -dimetilpirano) flavona de fórmula molecular C22H20O<sub<7, isolado de plantas da espécie Neoraputia paraensis, que cristaliza-se no sistema monoclínico, grupo espacial C2/c, com os seguintes parâmetros de cela unitária: a = 13,651(1), b= 23,428(2),c= 13,725(1) &#197; &#946= 119,528(4)&#176, V=3819,6(5)A&#9463 , Dc = 1,366g cm-3 e Z =8 moléculas por cela unitária. A estrutura foi resolvida através da aplicação de Métodos Diretos. Os índices de discordância finais são: R= 0,0509, Rw = 0,0530 para 1743 reflexões com I &#8805 3&#963(I) e Ra11=0,157. A estrutura foi refinada fazendo uso dos cálculos de Fourier Diferença e pelo método de mínimos quadrados usando matriz completa. A molécula apresenta duas ligações de hidrogênio intramoleculares, de força média (distâncias O-O 2,558(3) e 2,674(4) &#946). O empacotamento cristalino apresenta duas outras ligações de hidrogênio intermoleculares, mais fracas, sendo feitas com as moléculas geradas pelo espelho c (distâncias O-O 2,830(3) e 2,992(3) &#946). O efeito destas ligações intermoleculares é o da formação de cadeias ao longo da direção [101]. / Initially, some considerations about X-ray diffraction, its laws, the factors for the correction of experimental data, a revision of the main Direct Methods for structure resolution, and comments on the refinement of the resulting structure are presented. Next, the structure determination of the compound 5,4\' -dihydroxy-3\'-5\'- dimethoxy-6,7(2\",2\' \')dimethylpyran)flavone is described The compound is isolated from plants of the species Neuroputia paraenesis and has the molecular formula C22H20O<sub<7. It crystallizes in the monoclinic system, space group C2/c, with the following unit cell parameters: a = 13.651(1), b= 23.428(2), c= 13.725(1) &#197; &#946= 119,528(4)&#176, V=3819,6(5)A&#9463 , Dc = 1,366g cm-3 e Z =8molecules per unit cell. The structure was solved applying Direct Methods. The final disagreement indices are: R= 0.0509, Rw= 0.0530 for 1743 reflections with &#8805 3&#963(I) and Ra11=0,157. The structure was refined applying Fourier difference calculations and full matrix least squares methods. The molecule shows two intramolecular hydrogen bonds of medium strength (distances O-O 2.558(3) and 2.674(4) &#946). The crystal packing shows also two weaker hydrogen bonds; these are formed between the molecules generated by the c mirror (distances O-O 2.830(3) and 2.992(3) &#946). The result of these intermolecular hydrogen bonds is the formation of chains in [10 1] direction.
6

Sistemas nano/microemulsionados como carreadores para derivado flavonoídico (FLAVONA)

Reis, Malu Maria Lucas dos 16 February 2017 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2018-05-21T15:38:50Z No. of bitstreams: 1 PDF - Malu Maria Lucas dos Reis.pdf: 17160924 bytes, checksum: 0afe6930cfc0eeac7ba0e0d6a32fa8a1 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2018-05-23T16:59:44Z (GMT) No. of bitstreams: 1 PDF - Malu Maria Lucas dos Reis.pdf: 17160924 bytes, checksum: 0afe6930cfc0eeac7ba0e0d6a32fa8a1 (MD5) / Made available in DSpace on 2018-05-23T16:59:44Z (GMT). No. of bitstreams: 1 PDF - Malu Maria Lucas dos Reis.pdf: 17160924 bytes, checksum: 0afe6930cfc0eeac7ba0e0d6a32fa8a1 (MD5) Previous issue date: 2017-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Infectious diseases are responsible for about 25% deaths worldwide and 45% in underdeveloped countries. Antimicrobials are usually used to fight an established infection, they aim either to eliminate or to impede bacterial growth without causing harm to the patient. Flavone, a molecule derived from flavonoids, has evidence of bactericidal activity, with LogP of 3.37 which indicates high lipophilicity. Therefore, it needs a carrier system with lipophilic characteristics, such as microemulsions (ME) and nanoemulsions (NE) O/A, that are systems indicated to its incorporation and use as a novel drug delivery system (NDDS). The aim of this work was to develop nano/microemulsion systems for the incorporation of flavone, aiming topical application, characterizing them physico-chemically, defining a methodology for drug dosing. For the development of the systems and for the choice of formulations to be studied, the construction of the pseudo-ternary phase diagram was performed, followed by incorporation of the drug (1 mg/mL). From this, the physicochemical characterization of the samples was initiated: macroscopic evaluation, isotropy, pH measurement, refractive index, differential scanning calorimetry (DSC), transmission electron microscopy (MET), Zeta potential, droplet size and polydispersity index. In addition, the validation of an analytical method for flavone assay by UV-VIS spectrophotometer and high-performance liquid chromatography (HPLC) was performed. The NE developed was composed of 10.8% oil phase (isopropyl myristate), 25.87% surfactants (polyethylene glycol (15)-hydroxystearate/sorbitan monooleate 80) and 63.33% water. The ME has 34.5% oil phase, 34.5% surfactants and 31% water. Through isotropy, DSC and MET it was possible to prove that the nanoemulsion is O/A and the ME is a bicontinuous system. The analytical methods were validated, both linear, selective, accurate and robust. The present study was relevant for the area of pharmaceutical technology. We sought to develop novel systems with relevant therapeutic potential, since the proposed systems are unprecedented and the drug has the potential to treat antimicrobial diseases. / As doenças infecto-contagiosas são responsáveis por cerca de 25% das mortes em todo o mundo e 45% nos países subdesenvolvidos. Os antimicrobianos são utilizados para combater uma infecção estabelecida, possuindo a finalidade de eliminar ou impedir o crescimento bacteriano, sem causar danos ao paciente. Os flavonoides surgem como mais uma alternativa no tratamento antibacteriano. A flavona, molécula derivada dos flavonoides, possui indícios de sua atividade bactericida, com LogP de 3,37, que indica alta lipofilia. Logo, necessitamos de um sistema carreador com características lipofílicas, sendo carreadores lipídicos, como as microemulsões (ME) e nanoemulsões (NE) do tipo O/A, sistemas indicados para a sua incorporação e utilização como um novo sistema de liberação de fármacos (NSLF). Os objetivos deste trabalho foram desenvolver sistemas nano/microemulsionados para incorporação da flavona, almejando a aplicação tópica, caracterizá-los físico-quimicamente, definir uma metodologia para doseamento do fármaco. Para o desenvolvimento dos sistemas e escolha das formulações a serem estudadas foi realizada a construção do diagrama de fases pseudo-ternário, seguido de incorporação do fármaco (1 mg/mL). A partir disso, iniciaram-se as devidas caracterizações físico-químicas das amostras: avaliação macroscópica, isotropia, medição do pH, índice de refração, calorimetria exploratória diferencial (DSC), microscopia eletrônica de transmissão (MET), potencial Zeta, tamanho de gotícula e índice de polidispersão, além da validação de método analítico para doseamento de flavona por espectrofotômetro UV-VIS e por cromatrografia líquida de alta eficiência (CLAE). A NE desenvolvida foi constituída de 10,8% de fase oleosa (miristato de isopropila), 25,87% de tensoativos (polietilenoglicol (15)-hidroxiestearato/monooleato de Sorbitan 80) e 63,33% de água. Já a microemulsão, possui 34,5% de fase oleosa, 34,5% de tensoativos e 31% de água. Através da isotropia, DSC e MET foi possível provar que a nanoemulsão é O/A e a microemulsão é bicontínua. Os métodos analíticos foram validados, sendo ambos linear, seletivos, precisos, exatos e robustos. O presente estudo mostrou-se relevante para área de tecnologia farmacêutica. Buscou-se desenvolver sistemas inéditos com potencialidade terapêutica relevante, pois os sistemas propostos são inéditos e o fármaco apresenta potencialidade para tratamento de doenças antimicrobianas.
7

Determinação da estrutura cristalina e molecular de uma flavona. / Determination of the crystalline structure and molecular of a flavone.

Jaime de Souza Junior 24 May 1996 (has links)
Neste trabalho apresenta-se inicialmente algumas considerações sobre a difração de raios-X, suas principais leis, fatores de correção dos dados experimentais, uma revisão sobre os principais Métodos Diretos de resolução da estrutura, e considerações sobre o refinamento da estrutura obtida. A seguir descreve-se a determinação da estrutura cristalina do produto natural 5,4\'-Dihidroxi-3\', 5\' -dimetoxi- 6,7 -(2\",2\" -dimetilpirano) flavona de fórmula molecular C22H20O<sub<7, isolado de plantas da espécie Neoraputia paraensis, que cristaliza-se no sistema monoclínico, grupo espacial C2/c, com os seguintes parâmetros de cela unitária: a = 13,651(1), b= 23,428(2),c= 13,725(1) &#197; &#946= 119,528(4)&#176, V=3819,6(5)A&#9463 , Dc = 1,366g cm-3 e Z =8 moléculas por cela unitária. A estrutura foi resolvida através da aplicação de Métodos Diretos. Os índices de discordância finais são: R= 0,0509, Rw = 0,0530 para 1743 reflexões com I &#8805 3&#963(I) e Ra11=0,157. A estrutura foi refinada fazendo uso dos cálculos de Fourier Diferença e pelo método de mínimos quadrados usando matriz completa. A molécula apresenta duas ligações de hidrogênio intramoleculares, de força média (distâncias O-O 2,558(3) e 2,674(4) &#946). O empacotamento cristalino apresenta duas outras ligações de hidrogênio intermoleculares, mais fracas, sendo feitas com as moléculas geradas pelo espelho c (distâncias O-O 2,830(3) e 2,992(3) &#946). O efeito destas ligações intermoleculares é o da formação de cadeias ao longo da direção [101]. / Initially, some considerations about X-ray diffraction, its laws, the factors for the correction of experimental data, a revision of the main Direct Methods for structure resolution, and comments on the refinement of the resulting structure are presented. Next, the structure determination of the compound 5,4\' -dihydroxy-3\'-5\'- dimethoxy-6,7(2\",2\' \')dimethylpyran)flavone is described The compound is isolated from plants of the species Neuroputia paraenesis and has the molecular formula C22H20O<sub<7. It crystallizes in the monoclinic system, space group C2/c, with the following unit cell parameters: a = 13.651(1), b= 23.428(2), c= 13.725(1) &#197; &#946= 119,528(4)&#176, V=3819,6(5)A&#9463 , Dc = 1,366g cm-3 e Z =8molecules per unit cell. The structure was solved applying Direct Methods. The final disagreement indices are: R= 0.0509, Rw= 0.0530 for 1743 reflections with &#8805 3&#963(I) and Ra11=0,157. The structure was refined applying Fourier difference calculations and full matrix least squares methods. The molecule shows two intramolecular hydrogen bonds of medium strength (distances O-O 2.558(3) and 2.674(4) &#946). The crystal packing shows also two weaker hydrogen bonds; these are formed between the molecules generated by the c mirror (distances O-O 2.830(3) and 2.992(3) &#946). The result of these intermolecular hydrogen bonds is the formation of chains in [10 1] direction.
8

Développement de nouveaux agents antiparasitaires : vers la synthèse totale de la cissampeloflavone et de dérivés / Development of novel antiparasitic agents : towards the total synthesis of cissampeloflavone and derivatives

Thevenin, Marion 27 September 2013 (has links)
Les maladies tropicales provoquées par des parasites protozoaires tels que Trypanosoma brucei, Plasmodium falciparum et Leishmania donovani, infectent des milliards d'individus dans le monde et en tuent des millions chaque année. Actuellement, les phénomènes de résistance face aux thérapies actuelles utilisées pour traiter ces maladies dites " négligées " deviennent inquiétants et problématiques. Par conséquent, la découverte de nouvelles classes de molécules bioactives antiparasitaires est primordiale.C'est dans ce contexte que s'inscrit ce travail de thèse. La cissampeloflavone est un dimère chalcone-flavone isolé en 2003 d’une plante vénézuélienne, Cissampelos pareira. Cette molécule a démontré une bonne activité contre T. brucei (CI50 = 1 µM). Par ailleurs, des études de modélisation moléculaire ont prédit que son dérivé 4-désoxycissampeloflavone possèderait une bonne affinité pour une enzyme essentielle à la survie du parasite. Pour ces raisons, nous avons entrepris la synthèse totale de ces deux molécules originales jamais réalisée à ce jour.Des analogues simplifiés ont d’abord été synthétisés afin de mettre au point le schéma réactionnel pour former la cissampeloflavone et la 4-désoxycissampeloflavone. Ces composés ont pour base commune le noyau benzofurane qui porte soit la " partie chalcone " soit la " partie flavone " de ces dimères. Les deux synthèses totales ont ensuite été entreprises.Ce travail de thèse a notamment permis la création d'une librairie d'analogues benzofuranes polysubstitués, la découverte d'une réaction de méthylénation originale et la formation de nouveaux dérivés furanoflavones. La plupart ont été évalués sur T. brucei, P. falciparum et L. donovani. Plusieurs d'entre eux ont présenté une activité trypanocide intéressante et prometteuse. / Tropical diseases caused by protozoan parasites such as Trypanosoma brucei, Plasmodium falciparum and Leishmania donovani, infect billions of people worldwide and kill millions of them every year. Nowadays, resistance phenomena against actual therapies used to treat these " neglected " diseases are becoming worring and problematic. Therefore, discovery of new classes of antiparasitic bioactive molecules is primordial.This is the aim of this PhD work. Cissampeloflavone is a chalcone-flavone dimer isolated in 2003 from a Venezuelan plant, Cissampelos pareira. This molecule has showed a good activity against Trypanosoma brucei (IC50 = 1 µM). Besides, molecular docking studies have predicted that its derivative 4-desoxycissampeloflavone would possess a good affinity for an essential enzyme for parasite survival. For these reasons, we undertook the total synthesis of these two original molecules never carried out to date.Simplified analogues have been prepared in order to elaborate a synthetic pathway to form cissampeloflavone and 4-desoxycissampeloflavone. These compounds possess the benzofuran ring as common core which bears either the "chalcone part" or the "flavone part" of these dimers. The total syntheses were then undertaken.This PhD work has particularly enabled the creation of a polysubstituted benzofuran library, the discovery of an original methylenation reaction and the formation of new furanoflavone derivatives. Most of them were evaluated on T. brucei, P. falciparum and L. donovani. Several compounds have showed an interesting and promising trypanocidal activity.
9

Quantification of Two Isomeric Flavones in Rat Colon Tissue Using Reverse Phase High Performance Liquid Chromatography

Whitted, Crystal L., Palau, Victoria E., Torrenegra, Ruben D., Rodriguez, Oscar E., Harirforoosh, Sam 07 January 2017 (has links)
Background: Antineoplastic activity has been previously shown for two isomeric flavones, 5,7-dihydroxy-3,6,8-trimethoxy flavone (flavone A) and 3,5-dihydroxy-6,7,8-trimethoxy flavone (flavone B), against colon cancer cell lines (Thomas et al. in PLoS ONE 7:e39806, 5). Here, we present modified methods for the extraction and quantification of flavones A and B in rat colon tissue after intravenous dosing via high performance liquid chromatography, from the originally described procedure for extraction and quantification in rat plasma (Whitted et al. in J Chromatogr B Analyt Technol Biomed Life Sci 1001:150-155, 7). Results: Modifications included tissue homogenization (1 g tissue: 2 mL water), filtration of the supernatant with a PVDF membrane, and the use of only one calibration curve to determine the concentration of each flavone in colon tissue. Good separation was achieved and representative equations were linear with r 2 ≥ 0.99 for both flavones. Precision and accuracy for flavone A ranged from 0.88-24.03 and 109-116%. Precision and accuracy for flavone B ranged from 1.62-33.56 and 98-113%. Concentrations of 1639 ± 601 ng/g flavone A and 5975 ± 2480 ng/g of flavone B were detected in rat colon tissue 6 h post dosing. Conclusions: Modifications to the extraction methods for flavone A and flavone B from rat colon tissue had good separation, precision, and accuracy.
10

Development of Reversed-Phase High Performance Liquid Chromatography Methods for Quantification of Two Isomeric Flavones and the Application of the Methods to Pharmacokinetic Studies in Rats

Whitted, Crystal L., Palau, Victoria E., Torrenegra, Ruben D., Harirforoosh, Sam 05 September 2015 (has links)
Isomers 5,7-dihydroxy-3,6,8-trimethoxy-2-phenyl-4H-chromen-4-one (5,7-dihydroxy-3,6,8 trimethoxy flavone) (flavone A) and 3,5-dihydroxy-6,7,8-trimethoxy-2-phenyl-4H-chromen-4-one (3,5-dihydroxy-6,7,8-trimethoxy flavone) (flavone B) have recently demonstrated differential antineoplastic activities against pancreatic cancer in vitro. These studies also indicated that these compounds target highly tumorigenic cells while sparing normal cells. The in vivo antitumor activities of these flavones have not been determined, and detection protocols for these compounds are needed to conduct pre-clinical assays following intravenous dosing. Here, we report methods developed using acetonitrile to extract two flavone isomers and corresponding internal standards, celecoxib and diclofenac, from rat plasma. Separation was achieved using a Shimadzu liquid chromatography system with a C18 column and mobile phase acetonitrile/water (60:40 and 70:30 for flavones A and B, respectively) containing 0.2% acetic acid and 0.05% triethylamine at a flow rate of 0.4mL/min and detection at 245nm. Calibration curves ranging from 250 to 2500ng/mL and 2500 to 100,000ng/mL for both flavones were linear (r2≥0.99) with the lower limits of quantification being 250ng/mL. Recovery of concentrations 250, 1000, 2500, 5000, and 100,000ng/mL ranged from 87 to 116% and 84 to 103% (n=3) for flavone A and B, respectively. Stability of both flavones after a freezing/thawing cycle yielded a mean peak ratio ≥0.92 when compared to freshly extracted samples. Intravenous administration of a 20mg/kg dose in rats yielded half-lives of 83.68±56.61 and 107.45±53.31min with clearance values of 12.99±13.78 and 80.79±35.06mL/min/kg for flavones A and B, respectively.

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