- Practical synthesis of naringenin
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Two routes for the synthesis of the flavanone naringenin are described. In the first, 3,5-dimethoxyphenol is converted to 2-hydroxy- 4,6-dimethoxyacetophenone and then by condensation with anisaldehyde to 2′-hydroxy-4,4′,6′-trimethoxychalcone. The chalcone is then cyclised with aqueous hydrochloric acid and demethylated with pyridine hydrochloride to form naringenin in 45% overall yield. The condensation of 2-hydroxy-4,6-dimethoxyacetophenone with anisaldehyde could also directly produce 4′,5,7-trimethoxyflavanone, which was then converted into naringenin in 60% overall yield. In the second route, a single step for the preparation of the chalcone is used in which 1,3,5-trimethoxybenzene is acylated with p-methoxycinnamic acid. Although the synthesis of naringenin is achieved in a lower overall yield of 29%, the process is simpler.
- Wang, Qian,Yang, Jian,Zhang, Xiang-Ming,Zhou, Lei,Liao, Xia-Li,Yang, Bo
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Read Online
- Total synthesis of apigenin
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An efficient method for the synthesis of apigenin (4',5,7- trihydroxyflavone, a traditional medicine) from phloroglucinol and anisaldehyde has been developed. This transformation features a green method for hydroxyl protection as methyl ethers and a different way for cyclisation using iodine in DMSO. The overall yield of 40% is satisfactory.
- Wang, Jin,Zhou, Rong-Guang,Wu, Ting,Yang, Tao,Qin, Qi-Xue,Li, Li,Yang, Bo,Yang, Jian
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- An improved synthesis of apigenin
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Two routes for the synthesis of the flavone apigenin are described. In the first, taxicatigenin was converted to 2-hydroxy-4,6- dimethoxyacetophenone and then by condensation with anisaldehyde to 2′-hydroxy-4,4′,6′-trimethoxychalcone. The latter was cyclised with iodine and demethylated with pyridine hydrochloride to form apigenin in 53% overall yield. In the second route, a single step for the preparation of the chalcone was used in which 1,3,5-trimethoxybenzene was acylated with p-methoxycinnamic acid. Although the synthesis of apigenin was achieved in a lower overall yield of 34%, the process was simpler.
- Wang, Qian,Cui, Wei,Liu, Man,Zhang, Ji,Liao, Rong-Qiang,Liao, Xia-Li,Yang, Jian
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Read Online
- Insect antifeedant flavonoids from Gnaphalium affine D. Don
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The antifeedant flavonoids, 5-hydroxy-3,6,7,8,4'-pentamethoxyflavone (1), 5-hydroxy-3,6,7,8-tetramethoxyflavone (2), 5,6-dihydroxy-3,7- dimethoxyflavone (3), and 4,4',6'-trihydroxy-2'-methoxychalcone (4), have been isolated from cudweed Gnaphalium affine D. Don (Compositae). Four natural flavonoids showed insect antifeedant activity against the common cutworm (Spodoptera litura F.). These flavonoids were detected in small amounts in the plant by HPLC analysis, but these natural compounds had strong antifeedant activity against the common cutworm. On the other hand, 4 was detected in a large amount in the plant, but this compound had only a slight activity. Therefore, these natural compounds were regarded as one of the plant's defensive systems against phytophagous insects along with the woolly plant surface. As for the structure-activity relationship, it is an advantage for antifeedant activity to have no oxy-substituents on the B-ring of the flavonoid but have an ether linkage such as a pyran in the chemical structure.
- Morimoto, Masanori,Kumeda, Sumiko,Komai, Koichiro
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Read Online
- Flavokawain a induces apoptosis in MCF-7 and MDA-MB231 and inhibits the metastatic process in vitro
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Introduction: The kava-kava plant (Piper methsyticum) is traditionally known as the pacific elixir by the pacific islanders for its role in a wide range of biological activities. The extract of the roots of this plant contains a variety of interesting mol
- Abu, Nadiah,Akhtar, M. Nadeem,Yeap, Swee Keong,Lim, Kian Lam,Ho, Wan Yong,Zulfadli, Aimi Jamil,Omar, Abdul Rahman,Sulaiman, Mohd Roslan,Abdullah, Mohd Puad,Alitheen, Noorjahan Banu
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Read Online
- Application of human PCID2 protein in preparation or screening of anti-tumor drugs and compound with anti-tumor activity
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The invention belongs to the technical field of biotechnology and gene therapy, and particularly relates to application of human PCID2 protein in preparation or screening of anti-tumor drugs and an anti-tumor compound. It is found that the PCID2 gene promotes tumor cell proliferation and regulates the cell cycle, is a key molecule for regulating tumor generation and development, and can be used as a target protein for preparing or screening anti-tumor drugs; meanwhile, human PCID2 protein is used as target protein, a class of PCID2 protein targeting antitumor compounds are screened out through a molecular docking technology, and the compounds can significantly inhibit tumor cell proliferation and promote tumor cell apoptosis.
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Paragraph 0094-0096; 0102-0103; 0123
(2021/06/02)
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- Novel chromenone derivatives having substituted biphenyl group and a pharmaceutical composition for prevention or treatment of allergic diseases compring the same
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The present invention relates to: a novel chromenone derivative compound capable of effectively suppressing an allergic immune response by inhibiting signal transduction mediated by thymic stromal lymphopoietin (TSLP); and a pharmaceutical composition capable of fundamentally preventing or treating various allergic diseases by using the same.COPYRIGHT KIPO 2021
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Paragraph 0076-0083; 0085-0089
(2020/11/26)
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- Design, synthesis and biological evaluation of dimethyl cardamonin (DMC) derivatives as P-glycoprotein-mediated multidrug resistance reversal agents
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Background: P-glycoprotein (P-gp) has been regarded as an important factor in the multidrug resistance (MDR) of tumor cells within the last decade, which can be solved by inhibiting P-gp to reverse MDR. Thus, it is an effective strategy to develop inhibitor of P-gp. Objective: In this study, the synthesis of a series of derivatives had been carried out by bioisosterism design on the basis of Dimethyl Cardamonin (DMC). Subsequently, we evaluated their reversal activities as potential P-glycoprotein (P-gp)-mediated Multidrug Resistance (MDR) agents. Methods: Dimethyl cardamonin derivatives were synthesized from acetophenones and the corresponding benzaldehydes in the presence of 40% KOH by Claisen-Schmidt reaction. Their cytotoxicity and reversal activities in vitro were assessed with MTT. Moreover, the compound B4 was evaluated by Doxorubicin (DOX) accumulation, Western blot and wound-healing assays deeply. Results and Discussion: The results showed that compounds B2, B4 and B6 had the potency of MDR reversers with little intrinsic cytotoxicity. Meanwhile, these compounds also demonstrated the capability to inhibit MCF-7 and MCF-7/DOX cells migration. Besides, the most compound B4 was selected for further study, which promoted the accumulation of DOX in MCF-7/DOX cells and inhibited the expressionof P-gp at protein levels. Conclusion: The above findings may provide new insights for the research and development of P-gp-mediated MDR reversal agents.
- Liu, Jianwen,Ma, Lei,Shi, Ximeng,Yin, Huanhuan,Zhao, Yuyu,Zhou, Licheng
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p. 1270 - 1282
(2020/10/06)
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- Development of a novel nitric oxide (NO) production inhibitor with potential therapeutic effect on chronic inflammation
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Inflammation is a complex biological response to stimuli. Activated macrophages induced excessively release of pro-inflammatory cytokines and mediators such as endogenous radical nitric oxide (NO) play a significant role in the progression of multiple inflammatory diseases. Both natural and synthetic chalcones possess a wide range of bioactivities. In this work, thirty-nine chalcones and three related compounds, including several novel ones, based on bioactive kava chalcones were designed, synthesized and their inhibitory effects on NO production in RAW 264.7 cells were evaluated. The novel compound (E)-1-(2′-hydroxy-4′,6′-dimethoxyphenyl)-3-(3-methoxy-4-(3-morpholinopropoxy)phenyl)prop-2-en-1-one (53) exhibited a better inhibitory activity (84.0%) on NO production at 10 μM (IC50 = 6.4 μM) with the lowest cytotoxicity (IC50 > 80 μM) among the tested compounds. Besides, western blot analysis indicated that compound 53 was a potent down-regulator of inducible nitric oxide synthase (iNOS) protein. Docking study revealed that compound 53 also can dock into the active site of iNOS. Furthermore, at the dose of 10 mg/kg/day, compound 53 could both significantly suppress the progression of inflammation on collagen-induced arthritis (CIA) and adjuvant-induced arthritis (AIA) models. In addition, the structure-activity relationship (SAR) of the kava chalcones based analogs was also depicted.
- Chen, Lijuan,Fan, Tiantian,Lei, Xiangui,Teichmann, Alexander Tobias,Wang, Amu,Wang, Chao,Wei, Zhe,Wieland, Frank Heinrich,Yang, Youzhe,Yin, Jinxiang,Zhou, Li,Zhu, Yue
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supporting information
(2020/03/24)
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- Synthesis method of isolicoflavonol
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The invention provides a synthesis method of isolicoflavonol, which comprises the following steps: carrying out condensation reaction on 2,4-O-R1(protective group, the same below)-6-hydroxyacetophenone and 4-O-R2(protective group, the same below)-benzaldehyde to generate 2',4'-O-R1-6'-hydroxy-4-O-R2-chalcone; oxidizing the chalcone to generate flavonol; carrying out selective protection on 3-OH ofthe flavonol to obtain 3,5,7-O-R1-4'-O-R2-flavonol; removing the protecting group R2 from the 3,5,7-O-R1-4'-O-R2-flavonol to obtain 3,5,7-O-R1-4'-hydroxyflavonol; carrying out 1,1-dimethylpropargyl reaction on the 4,4'-OH site to obtain 3,5,7-O-R1-4'-O-(1',1''-dimethyl propargyl)flavonol; carrying out partial hydrogenation on the alkynyl of the 3,5,7-O-R1-4'-O-(1',1''-dimethyl propargyl)flavonolunder the action of a catalyst to obtain 3,5,7-O-R1-4'-O-(1',1''-dimethylpropenyl)flavonol and carrying out Claisen rearrangement on the 3,5,7-O-R1-4'-O-(1',1''-dimethylpropenyl)flavonol to obtain 3,5,7-O-R1-isolicoflavonol, and removing the protecting group R1 from the 3,5,7-O-R1-isolicoflavonol to obtain the isolicoflavonol.
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Paragraph 0111; 0202-0208
(2020/12/29)
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- Attrition-enhanced deracemization and absolute asymmetric synthesis of flavanones from prochiral precursors
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Seven racemic 5,7-dimethoxyflavanones afforded conglomerate crystals upon recrystallization from a solvent. Three methodologies were investigated to achieve asymmetric transformation based on dynamic crystallization of the chiral conglomerate system. The first was chiral symmetry breaking of racemic flavanones by attrition-enhanced deracemization. Continuous suspension of racemic flavanones in a small amount of propanol in the presence of a base (1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)) and glass beads promoted chiral symmetry breaking and converted the flavanones to crystals of (+)- or (-)-enantiomers with 78 to 99% ee. The second method involved cyclization of the intermediate aldol product to give optically active flavanone with 90% ee involving a reversible oxa-Michael addition reaction with attrition-enhanced deracemization. The third was a reaction starting from prochiral 2-hydroxy-4,6-dimethoxyacetophenone and 2-naphthaldehyde under basic conditions, which gave the corresponding flavanone in 89% ee.
- Kasashima, Yoshio,Mino, Takashi,Sakamoto, Masami,Shimizu, Waku,Uemura, Naohiro,Yoshida, Yasushi
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p. 5676 - 5681
(2020/10/13)
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- Melanogenic inhibition and toxicity assessment of flavokawain A and B on B16/F10 melanoma cells and zebrafish (Danio rerio)
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Excessive production of melanin implicates hyperpigmentation disorders. Flavokawain A (FLA) and flavokawain B (FLB) have been reported with anti-melanogenic activity, but their melanogenic inhibition and toxicity effects on the vertebrate model of zebrafish are still unknown. In the present study, cytotoxic as well as melanogenic effects of FLA and FLB on cellular melanin content and tyrosinase activity were evaluated in α-MSH-induced B16/F10 cells. Master regulator of microphthalmia-associated transcription factor (Mitf) and the other downstream melanogenic-related genes were verified via quantitative real time PCR (qPCR). Toxicity assessment and melanogenesis inhibition on zebrafish model was further observed. FLA and FLB significantly reduced the specific cellular melanin content by 4.3-fold and 9.6-fold decrement, respectively in α-MSH-induced B16/F10 cells. Concomitantly, FLA significantly reduced the specific cellular tyrosinase activity by 7-fold whilst FLB by 9-fold. The decrement of melanin production and tyrosinase activity were correlated with the mRNA suppression of Mitf which in turn down-regulate Tyr, Trp-1 and Trp-2. FLA and FLB exhibited non-toxic effects on the zebrafish model at 25 and 6.25 μM, respectively. Further experiments on the zebrafish model demonstrated successful phenotype-based depigmenting activity of FLA and FLB under induced melanogenesis. To sum up, our findings provide an important first key step for both of the chalcone derivatives to be further studied and developed as potent depigmenting agents.
- Abdul Bahari, Mohammad Nazri,Ahmad, Syahida,Akhtar, Muhammad Nadeem,Balia Yusof, Zetty Norhana,Latif, Naimah,Md Razip, Nurliyana Najwa,Mohd Ma’in, Farah Idayu,Sakeh, Nurshafika Mohd
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- Chalcone analogue and application thereof
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The invention discloses a chalcone analogue and application thereof, wherein the structure of the chalcone analogue is shown as a formula (I), and R is selected from substituted or unsubstituted arylor heteroaryl; the substituent groups on the aryl group
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Paragraph 0034-0040; 0047-0048
(2020/07/02)
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- Total synthesis of wikstrol A and wikstrol B
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The first total synthesis of wikstrol A and wikstrol B was achieved by employing aldol reaction, Sharpless asymmetric dihydroxylation, regioselective iodination, Sonogashira coupling, and rhodium-catalyzed oxidative coupling as key steps. The structure of the key intermediate for wikstrol A was confirmed via its derivative by single-crystal X-ray analysis.
- Lu, Kui,Li, Ming,Huang, Yuna,Sun, Yuanyuan,Gong, Zhi,Wei, Qijun,Zhao, Xia,Zhang, Yongmin,Yu, Peng
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p. 8206 - 8213
(2019/09/19)
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- Synthesis of Benzopyran-Fused Flavone Derivatives via Microwave-Assisted Intramolecular C-H Activation
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A microwave-assisted intramolecular direct arylation method for the synthesis of benzopyran-fused flavone derivatives containing natural flavone backbones is described. Different polyalkoxy flavones were synthesized and functionalized with 2-bromobenzyl bromide. The resulting compounds were subjected to palladium-catalyzed intramolecular direct arylation reactions supported by microwave irradiation to produce fused tetracyclic flavones. In the case of the 7-substituted chrysin derivative, the regioselectivity of the coupling was also examined.
- Sipos, Zoltán,Kónya, Krisztina
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supporting information
p. 1610 - 1620
(2018/03/21)
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- Design, synthesis and docking studies of flavokawain B type chalcones and their cytotoxic effects on MCF-7 and MDA-MB-231 cell lines
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Flavokawain B (1) is a natural chalcone extracted from the roots of Piper methysticum, and has been proven to be a potential cytotoxic compound. Using the partial structure of flavokawain B (FKB), about 23 analogs have been synthesized. Among them, compounds 8, 13 and 23 were found in new FKB derivatives. All compounds were evaluated for their cytotoxic properties against two breast cancer cell lines, MCF-7 and MDA-MB-231, thus establishing the structure-activity relationship. The FKB derivatives 16 (IC50 = 6.50 ± 0.40 and 4.12 ± 0.20 μg/mL), 15 (IC50 = 5.50 ± 0.35 and 6.50 ± 1.40 μg/mL) and 13 (IC50 = 7.12 ± 0.80 and 4.04 ± 0.30 μg/mL) exhibited potential cytotoxic effects on the MCF-7 and MDA-MB-231 cell lines. However, the methoxy group substituted in position three and four in compound 2 (IC50 = 8.90 ± 0.60 and 6.80 ± 0.35 μg/mL) and 22 (IC50 = 8.80 ± 0.35 and 14.16 ± 1.10 μg/mL) exhibited good cytotoxicity. The lead compound FKB (1) showed potential cytotoxicity (IC50 = 7.70 ± 0.30 and 5.90 ± 0.30 μg/mL) against two proposed breast cancer cell lines. It is evident that the FKB skeleton is unique for anticancer agents, additionally, the presence of halogens (Cl and F) in position 2 and 3 also improved the cytotoxicity in FKB series. These findings could help to improve the future drug discovery process to treat breast cancer. A molecular dynamics study of active compounds revealed stable interactions within the active site of Janus kinase. The structures of all compounds were determined by 1H-NMR, EI-MS, IR and UV and X-ray crystallographic spectroscopy techniques.
- Bakar, Addila Abu,Akhtar, Muhammad Nadeem,Ali, Norlaily Mohd,Yeap, Swee Keong,Quah, Ching Kheng,Loh, Wan-Sin,Alitheen, Noorjahan Banu,Zareen, Seema,Ul-Haq, Zaheer,Shah, Syed Adnan Ali
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- Targeting the MDM2-p53 protein-protein interaction with prenylchalcones: Synthesis of a small library and evaluation of potential antitumor activity
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Prenylation of several bioactive scaffolds is a very interesting strategy used in Medicinal Chemistry in order to improve biological/pharmacological effects. A small library of prenylchalcones was synthesized and evaluated for the ability to inhibit the MDM2-p53 interaction using a yeast-based assay. The capacity of all synthesized prenylchalcones and their non-prenylated precursors to inhibit the growth of human colon tumor HCT116 cells was also evaluated. The obtained results led to the identification of a hit compound, prenylchalcone 2e, which behaved as potential inhibitor of the MDM2-p53 interaction in yeast, and showed improved cytotoxicity against human tumor cells expressing wild-type p53, including liver hepatocellular carcinoma HepG2, breast adenocarcinoma MCF-7, and malignant melanoma A375 cells. In colon cancer cells, it was also shown that the growth inhibitory effect of prenylchalcone 2e was associated with the induction of cell cycle arrest, apoptosis, and increased protein expression levels of p53 transcriptional targets. Moreover, computational docking studies were performed in order to predict docking poses and residues involved in the MDM2-p53 potential interaction.
- Brand?o, Pedro,Loureiro, Joana B.,Carvalho, Sylvie,Hamadou, Meriem Hadjer,Cravo, Sara,Moreira, Joana,Pereira, Daniela,Palmeira, Andreia,Pinto, Madalena,Saraiva, Lucília,Cidade, Honorina
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p. 711 - 721
(2018/07/29)
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- Synthesis of 5-subsituted flavonols via the Algar-Flynn-Oyamada (AFO) reaction: The mechanistic implication
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Herein, we report a synthetic method with improved selectivity for 5-substituted flavonols via the Algar-Flynn-Oyamada reaction (AFO), by using of sodium carbonate/hydrogen peroxide A series of 5-substituted flavonols was obtained with moderate to high yields. The mechanism of the AFO reaction was elucidated. LCMS analysis and in situ 1H NMR analysis indicated that the epoxide was involved in the transformation from chalcone to flavonol and/or aurone under alkaline base/peroxide conditions.
- Shen, Xianyan,Zhou, Qiang,Xiong, Wei,Pu, Wenchen,Zhang, Wei,Zhang, Guolin,Wang, Chun
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p. 4822 - 4829
(2017/07/17)
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- Total synthesis of agalloside, isolated from: Aquilaria agallocha, by the 5-O-glycosylation of flavan
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Agalloside (1) is a neural stem cell differentiation activator isolated from Aquilaria agallocha by our group using Hes1 immobilized beads. We conducted the first total synthesis of agalloside (1) via the 5-O-glycosylation of flavan 25 using glycosyl fluoride 20 in the presence of BF3·Et2O. Subsequent oxidation with DDQ to flavanone 2 and deprotection successively provided agalloside (1). This synthetic strategy holds promise for use in the synthesis of 5-O-glycosylated flavonoids. The synthesized agalloside (1) accelerated neural stem cell differentiation, which is a result comparable to that for the naturally occurring compound 1.
- Arai, Midori A.,Yamaguchi, Yumi,Ishibashi, Masami
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p. 5025 - 5032
(2017/07/10)
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- New homoisoflavonoid analogues protect cells by regulating autophagy
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As a special group of naturally occurring flavonoids, homoisoflavonoids have been discovered as active components of several traditional Chinese medicines for nourishing heart and mind. In this study, twenty homoisoflavonoid analogues, including different substitution groups on rings A and B, as well as heteroaromatic B ring, were synthesized and evaluated for their cardioprotective and neuroprotective activities. In a H2O2-induced H9c2 cardiomyocytes injury assay, nine homoisoflavonoid analogues showed promising activities in the same level as the positive control, diazoxide. Six cardioprotective compounds with representative structure diversities were then evaluated for their neuroprotective effects on MPP+ induced SH-SY5Y cell injury model. Furthermore, autophagy inducing monodansylcadaverine (MDC) fluorescence staining methods and molecular docking studies indicated the action mechanism of these compounds may involve autophagy regulating via class I PI3K signaling pathway.
- Gan, Li-She,Zeng, Lin-Wei,Li, Xiang-Rong,Zhou, Chang-Xin,Li, Jie
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supporting information
p. 1441 - 1445
(2017/03/08)
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- Mechanisms of action and structure-activity relationships of cytotoxic flavokawain derivatives
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22 Flavokawain derivatives (FKd) were obtained by one step syntheses in order to conduct a SAR study to understand the structural requirements for optimum and selective cytotoxicity. FKd and natural flavokawains A and B found into kava, a South Pacific traditional beverage, were evaluated against nine cancer and one healthy cell lines. The targeted cell cycle phases as well as the effects on the induction of apoptosis and cell cycle protein levels were investigated. Therapeutic improvements (more activity and selectivity) were achieved with FKd compared to natural flavokawains and notably with the 2′,3,4′,6′-tetramethoxychalcone (FKd 19). FKd induced a G1/S arrest on p53 wild-type cells and an M arrest on p53 mutant-type, via the up-regulation of p21 and cyclin B1 proteins, followed by apoptosis. Moreover, FKd exhibited a 24?h-effect on Akt/mTor normal cells versus a 48?h-effect on Akt/mTor up-regulated cells. The SAR study resulted in the conclusion that trimethoxy A-ring allowed the best compromise between cytotoxicity and selectivity, as well as the substitution of the meta position on the B-ring and the use of halogens substituents.
- Thieury, Charlotte,Lebouvier, Nicolas,Le Guével, Rémy,Barguil, Yann,Herbette, Ga?tan,Antheaume, Cyril,Hnawia, Edouard,Asakawa, Yoshinori,Nour, Mohammed,Guillaudeux, Thierry
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p. 1817 - 1829
(2017/03/08)
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- An improved synthesis of apigenin and luteolin
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Apigenin and luteolin are the antioxidant flavonoids found in foods such as parsley, artichoke, basil and celery. Both of these compounds have shown the ability to protect cells against cancer and also to inhibit DNA oxidative damage. These flavonoids are part of many nutraceutical formulations available in the market. There is a need for the development of cost effective methodologies to produce them in large quantities. The synthetic process developed for both these compounds is general and can be applied for other flavonoids also. An industrially applicable high pure product, cost effective synthesis and general synthetic method has been developed and presented.
- Rambabu,Kumari,Baby Ramana,Ramani,Subbaraju,Hari Babu
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p. 1139 - 1143
(2016/03/01)
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- Synthesis, biological evaluation and molecular modelling of 2′-hydroxychalcones as acetylcholinesterase inhibitors
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A series of 2′-hydroxy- and 2′-hydroxy-4′,6′-dimethoxychalcones was synthesised and evaluated as inhibitors of human acetylcholinesterase (AChE). The majority of the compounds were found to show some activity, with the most active compounds having IC
- Sukumaran, Sri Devi,Chee, Chin Fei,Viswanathan, Geetha,Buckle, Michael J. C.,Othman, Rozana,Rahman, Noorsaadah Abd.,Chung, Lip Yong
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- Design and synthesis of chalcone derivatives as potent tyrosinase inhibitors and their structural activity relationship
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Browning of fruits and vegetables is a serious issue in the food industry, as it damages the organoleptic properties of the final products. Overproduction of melanin causes aesthetic problems such as melisma, freckles and lentigo. In this study, a series of chalcones (1-10) have been synthesized and examined for their tryrosinase inhibitory activity. The results showed that flavokawain B (1), flavokawain A (2) and compound 3 were found to be potential tyrosinase inhibitors, indicating IC50 14.20-14.38 μM values. This demonstrates that 4-substituted phenolic compound especially at ring A exhibited significant tyrosinase inhibition. Additionally, molecular docking results showed a strong binding affinity for compounds 1-3 through chelation between copper metal and ligands. The detailed molecular docking and SARs studies correlate well with the tyrosinase inhibition studies in vitro. The structures of these compounds were elucidated by the 1D and 2D NMR spectroscopy, mass spectrometry and single X-ray crystallographic techniques. These findings could lead to design and discover of new tyrosinase inhibitors to control the melanine overproduction and overcome the economic loss of food industry.
- Akhtar, Muhammad Nadeem,Sakeh, Nurshafika M.,Zareen, Seema,Gul, Sana,Lo, Kong Mun,Ul-Haq, Zaheer,Shah, Syed Adnan Ali,Ahmad, Syahida
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- New developments in the synthesis of (e)-8-styrylflavones
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A novel route for the synthesis of new (E)-8-styrylflavones is reported. This methodology involves the regio- and stereoselective Heck cross-coupling reaction of 8-iodoflavones and styrene derivatives. The Heck precursors, 8-iodoflavones, were obtained through an efficient regioselective one-pot oxidative cyclization-iodination reaction of (E)-2′-hydroxychalcones by applying the iodine/dimethyl sulfoxide system.
- De Azevedo, Orlando D. C. C.,Seixas, Raquel S. G. R.,Silva, Artur M. S.
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p. 1379 - 1384
(2015/06/16)
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- Flavokawain derivative or pharmaceutically acceptable salt thereof having inhibitory activity on Hsp90 and medical use thereof
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The present invention relates to a flavokawain derivative or a pharmaceutically acceptable salt thereof having an activity for inhibiting Hsp90 and a medical use thereof wherein the flavokawain derivative comprises good effect of inhibiting Hsp90 and accordingly leads to decomposition of Hsp 90 client protein causing diseases related to cancer or neurodegenerative diseases by inhibiting Hsp90, thereby being used in drug medicine and healthy food products for preventing or treating Hsp 90 which is a mediated disease like diseases related to cancer or neurodegenerative diseases.COPYRIGHT KIPO 2015
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Paragraph 0083-0086
(2016/10/10)
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- Flavokawains B and C, melanogenesis inhibitors, isolated from the root of Piper methysticum and synthesis of analogs
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The ethanolic extract of the root of Piper methysticum was found to inhibit melanogenesis in MSH-activated B16 melanoma cells. Flavokawains B and C were isolated from this extract based on their anti-melanogenesis activity and found to inhibit melanogenesis with IC50 values of 7.7 μM and 6.9 μM, respectively. Flavokawain analogs were synthesized through a Claisen-Schmidt condensation of their corresponding acetophenones and benzaldehydes and were evaluated in terms of their tyrosinase inhibitory and anti-melanogenesis activities. Compound 1b was the most potent of these with an IC50 value of 2.3 μM in melanogenesis inhibition assays using MSH-activated B16 melanoma cells.
- Jeong, Hye-Jin,Lee, Chang Seok,Choi, Janggyoo,Hong, Yong Deog,Shin, Song Seok,Park, Jun Seong,Lee, John Hwan,Lee, Seokyong,Yoon, Kee Dong,Ko, Jaeyoung
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p. 799 - 802
(2015/02/19)
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- Chalcones with electron-withdrawing and electron-donating substituents: Anticancer activity against TRAIL resistant cancer cells, structure-activity relationship analysis and regulation of apoptotic proteins
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In the present study, a series of 46 chalcones were synthesised and evaluated for antiproliferative activities against the human TRAIL-resistant breast (MCF-7, MDA-MB-231), cervical (HeLa), ovarian (Caov-3), lung (A549), liver (HepG2), colorectal (HT-29), nasopharyngeal (CNE-1), erythromyeloblastoid (K-562) and T-lymphoblastoid (CEM-SS) cancer cells. The chalcone 38 containing an amino (-NH2) group on ring A was the most potent and selective against cancer cells. The effects of the chalcone 38 on regulation of 43 apoptosis-related markers in HT-29 cells were determined. The results showed that 20 apoptotic markers (Bad, Bax, Bcl-2, Bcl-w, Bid, Bim, CD40, Fas, HSP27, IGF-1, IGFBP-4, IGFBP-5, Livin, p21, Survivin, sTNF-R2, TRAIL-R2, XIAP, caspase-3 and caspase-8) were either up regulated or down regulated.
- Mai, Chun Wai,Yaeghoobi, Marzieh,Abd-Rahman, Noorsaadah,Kang, Yew Beng,Pichika, Mallikarjuna Rao
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supporting information
p. 378 - 387
(2014/04/17)
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- A novel synthesis of naringenin and related flavanones
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Efficient methods are reported for the preparation of naringenin (4',5,7-trihydroxyflavanone) which could be easily scaled-up. They have been applied to three other flavanones (6.hydroxyflavanone, 6,4'-dihydroxyflavanone, 6,3',4'-trihydroxyflavanone) suitably.
- Cui, Wei,Zhang, Ji,Wang, Qian,Gao, Kai,Zhang, Wei,Yang, Jian
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p. 686 - 689
(2015/02/19)
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- Synthesis of flavokawain analogues and their anti-neoplastic effects on drug-resistant cancer cells through Hsp90 inhibition
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Hsp90 is an ubiquitous molecular chaperone protein, which plays an important role in regulating maturation and stabilization of many oncogenic proteins. Due to its potential to simultaneously disable multiple signaling pathways, Hsp90 represents great promise as a therapeutic target of cancer. In this study, we synthesized flavokawain analogues and evaluated their biological activities against drug-resistant cancer cells. The study indicated that compound 1i impaired the growth of gefitinib-resistant non-small cell lung cancer (H1975), down-regulated the expression of Hsp90 client proteins including EGFR, Her2, Met, Akt and Cdk4, and upregulated the expression of Hsp70. The result strongly suggested that compound 1i inhibited the proliferation of cancer cells through Hsp90 inhibition. Overall, compound 1i could serve as a potential lead compound to overcome the drug resistance in cancer chemotherapy.
- Seo, Young Ho,Park, Sun You
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p. 1154 - 1158
(2014/05/06)
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- Aurones as histone deacetylase inhibitors: Identification of key features
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In this study, a total of 22 flavonoids were tested for their HDAC inhibitory activity using fluorimetric and BRET-based assays. Four aurones were found to be active in both assays and showed IC50 values below 20 μM in the enzymatic assay. Molecular modelling revealed that the presence of hydroxyl groups was responsible for good compound orientation within the isoenzyme catalytic site and zinc chelation.
- Zwick, Vincent,Chatzivasileiou, Alkiviadis-Orfefs,Deschamps, Nathalie,Roussaki, Marina,Simes-Pires, Claudia A.,Nurisso, Alessandra,Denis, Iza,Blanquart, Christophe,Martinet, Nadine,Carrupt, Pierre-Alain,Detsi, Anastasia,Cuendet, Muriel
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supporting information
p. 5497 - 5501
(2014/12/12)
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- Synthesis and biological evaluation of flavones and benzoflavones as inhibitors of BCRP/ABCG2
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Multidrug resistance (MDR) often leads to a failure of cancer chemotherapy. Breast Cancer Resistance Protein (BCRP/ABCG2), a member of the superfamily of ATP binding cassette proteins has been found to confer MDR in cancer cells by transporting molecules with amphiphilic character out of the cells using energy from ATP hydrolysis. Inhibiting BCRP can be a solution to overcome MDR.We synthesized a series of flavones, 7,8-benzofl avones and 5,6-benzo flavones with varying substituents at positions 3, 3′ and 4′ of the (benzo)fl avone structure. All synthesized compounds were tested for BCRP inhibition in Hoechst 33342 and pheophorbide A accumulation assays using MDCK cells expressing BCRP. All the compounds were further screened for their P-glycoprotein (P-gp) and Multidrug resistance-associated protein 1 (MRP1) inhibitory activity by calcein AM accumulation assay to check the selectivity towards BCRP. In addition most active compounds were investigated for their cytotoxicity. It was observed that in most cases 7,8-benzoflavones are more potent in comparison to the 5,6-benzoflavones. In general it was found that presence of a 3-OCH3 substituent leads to increase in activity in comparison to presence of OH or no substitution at position 3. Also, it was found that presence of 3′,4′-OCH3 on phenyl ring lead to increase in activity as compared to other substituents. Compound 24, a 7,8-benzoflavone derivative was found to be most potent being 50 times selective for BCRP and showing very low cytotoxicity at higher concentrations.
- Juvale, Kapil,Stefan, Katja,Wiese, Michael
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p. 115 - 126
(2013/10/01)
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- Reactivity assessment of chalcones by a kinetic thiol assay
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The electrophilic nature of chalcones (1,3-diphenylprop-2-en-1-ones) and many other α,β-unsaturated carbonyl compounds is crucial for their biological activity, which is often based on thiol-mediated regulation processes. To better predict their biological activity a simple screening assay for the assessment of the second-order rate constants (k2) in thia-Michael additions was developed. Hence, a clear structure-activity relationship of 16 differentially decorated hydroxy-alkoxychalcones upon addition of cysteamine could be established. Moreover, amongst other naturally occurring α,β-unsaturated carbonyl compounds k2 values for curcumin and cinnamaldehyde were gained while cinnamic acids or esters gave no or very slow reactions.
- Amslinger, Sabine,Al-Rifai, Nafisah,Winter, Katrin,W?rmann, Kilian,Scholz, Rebekka,Baumeister, Paul,Wild, Martin
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supporting information
p. 549 - 554
(2013/03/13)
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- Investigation of chalcones and benzochalcones as inhibitors of breast cancer resistance protein
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Breast cancer resistance protein (BCRP/ABCG2) belongs to the ATP binding cassette family of transport proteins. BCRP has been found to confer multidrug resistance in cancer cells. A strategy to overcome resistance due to BCRP overexpression is the investigation of potent and specific BCRP inhibitors. The aim of the current study was to investigate different multi-substituted chalcones for their BCRP inhibition. We synthesized chalcones and benzochalcones with different substituents (viz. OH, OCH3, Cl) on ring A and B of the chalcone structure. All synthesized compounds were tested by Hoechst 33342 accumulation assay to determine inhibitory activity in MCF-7 MX and MDCK cells expressing BCRP. The compounds were also screened for their P-glycoprotein (P-gp) and Multidrug resistance-associated protein 1 (MRP1) inhibitory activity in the calcein AM accumulation assay and were found to be selective towards inhibition of BCRP. Substituents at position 2′ and 4′ on chalcone ring A were found to be essential for activity; additionally there was a great influence of substituents on ring B. Presence of 3,4-dimethoxy substitution on ring B was found to be optimal, while presence of 2- and 4-chloro substitution also showed a positive effect on BCRP inhibition.
- Juvale, Kapil,Pape, Veronika F.S.,Wiese, Michael
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experimental part
p. 346 - 355
(2012/03/09)
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- A one-pot synthesis of aurones from substituted acetophenones and benzaldehydes: A concise synthesis of aureusidin
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A one-pot synthesis of aurones from substituted acetophenone and benzaldehyde has been developed on the basis of an improved Algar-Flynn-Oyamada reaction. By using this method, several aurones were prepared in three steps from commercial starting materials. The usefulness of this one-pot strategy was confirmed by a synthesis of aureusidin, an inhibitor of iodothyronine deiodinase, in 41% overall yield. In comparison with a two-step synthesis of this product from the same substrates, the one-pot strategy was more effective, giving a higher yield and requiring fewer and simpler operations. Georg Thieme Verlag Stuttgart New York.
- Zhao, Xiaolong,Liu, Jie,Xie, Zhixiang,Li, Ying
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experimental part
p. 2217 - 2224
(2012/09/22)
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- COMPOUNDS, THEIR SYNTHESES, AND THEIR USES
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Embodiments of the present invention provide compounds (such as Formula (I) compounds, Formula (II) compounds, and various embodiments thereof). Compositions comprising those compounds are also provided. Methods for their preparation are included. Also, uses of the compounds are included, such as administering and treating diseases (e.g., cancer and infections).
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Page/Page column 38-39
(2010/04/03)
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- Isolation and synthesis of flavonols and comparison of their antioxidant activity
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Phytochemical investigation of the leaves of Astragalus beckari yielded four flavonol aglycones, namely kaempferol, quercetin, 5-deoxy kaempferol and fisitin. These isolated compounds were then synthesised in the laboratory using the Algar-Flyn-Oyamad reaction. Antioxidant activity of both the isolated and synthesised flavonoids was compared using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay method. The isolated flavonoids were found to be more active.
- Hasan, Aurangzeb,Sadiq,Abbas,Mughal,Khan, Khalid M.,Ali, Muhammad
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experimental part
p. 995 - 1003
(2010/09/05)
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- Solution phase synthesis of a combinatorial library of chalcones and flavones as potent cathepsin v inhibitors
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Cathepsin V is a papain-like cysteine protease. It is involved in the control of human T cells (responsible for cell immunity), and presents the largest elastolytic activity among the proteolytic enzymes. Therefore, cathepsin V is a potential molecular ta
- Alvim, Joel,Severino, Richele P.,Marques, Emerson F.,Martinelli, Ariane M.,Vieira, Paulo C.,Fernandes, Joao B.,Da Silva, M. Fatima Das G. F.,Correa, Arlene G.
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experimental part
p. 687 - 695
(2010/11/18)
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- Natural and synthetic 2′-hydroxy-chalcones and aurones: Synthesis, characterization and evaluation of the antioxidant and soybean lipoxygenase inhibitory activity
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A series of 2′-hydroxy-chalcones and their oxidative cyclization products, aurones, have been synthesized and tested for their antioxidant and lipoxygenase inhibitory activity. The natural product aureusidin (31) was synthesized in high yield by a new approach. An extensive structure-relationship study was performed and revealed that several chalcones and aurones possess an appealing pharmacological profile combining high antioxidant and lipid peroxidation activity with potent soybean LOX inhibition.
- Detsi, Anastasia,Majdalani, Maya,Kontogiorgis, Christos A.,Hadjipavlou-Litina, Dimitra,Kefalas, Panagiotis
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experimental part
p. 8073 - 8085
(2010/03/24)
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- Structure - Activity relationship studies of chalcone leading to 3-hydroxy-4,3′,4′,5′-tetramethoxychalcone and its analogues as potent nuclear factor κB inhibitors and their anticancer activities
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Chalcone is a privileged structure, demonstrating promising anti-inflammatory and anticancer activities. One potential mechanism is to suppress nuclear factor kappa B (NF-κB) activation. The structures of chalcone-based NF-κB inhibitors vary significantly that there is minimum information about their structure-activity relationships (SAR). This study aims to establish SAR of chalcone-based compounds to NF-κB inhibition, to explore the feasibility of developing simple chalcone-based potent NF-κB inhibitors, and to evaluate their anticancer activities. Three series of chalcones were synthesized in one to three steps with the key step being aldol condensation. These candidates demonstrated a wide range of NF-κB inhibitory activities, some of low micromolar potency, establishing that structural complexity is not required for NF-κB inhibition. Lead compounds also demonstrate potent cytotoxicity against lung cancer cells. Their cytotoxicities correlate moderately well with their NF-κB inhibitory activities, suggesting that suppressing NF-κB activation is likely responsible for at least some of the cytotoxicities. One lead compound effectively inhibits lung tumor growth with no signs of adverse side effects.
- Srinivasan, Balasubramanian,Johnson, Thomas E.,Lad, Rahul,Xing, Chengguo
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experimental part
p. 7228 - 7235
(2010/08/19)
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- Synthesis, cytotoxicity, and anti-Trypanosoma cruzi activity of new chalcones
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Synthesis of a cytotoxic dihydrochalcone, first isolated from a traditional Amazonian medicinal plant Iryanthera juruensis Warb (Myristicaceae), followed by a comprehensive SAR analysis of saturated and unsaturated chalcone synthetic intermediates, led to the identification of analogues with selective and significant in vitro anti-Trypanosoma cruzi activity. Further SAR studies were undertaken with the synthesis of 21 new chalcones containing two allyloxy moieties that resulted in the discovery of 2′,4′-diallyloxy- 6′-methoxy chalcones with improved selectivity against this parasite at concentrations below 25 μM, four of which exhibited a selectivity index greater than 12.
- Aponte, José C.,Verástegui, Manuela,Málaga, Edith,Zimic, Mirko,Quiliano, Miguel,Vaisberg, Abraham J.,Gilman, Robert H.,Hammond, Gerald B.
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experimental part
p. 6230 - 6234
(2009/09/25)
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- Synthetic chalcones, flavanones, and flavones as antitumoral agents: Biological evaluation and structure-activity relationships
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A series of synthetic chalcones, flavanones, and flavones has been synthesized and evaluated for antitumor activity against the human kidney carcinoma cells TK-10, human mammary adenocarcinoma cells MCF-7 (estrogen receptor-positive), and human colon adenocarcinoma cells HT-29. The most active series is the chalcone ones with the best results against TK-10 and HT-29 cells. Fourteen out of 53 analyzed compounds resulted very active against at least two of the studied tumoral cells. Alkaline single cell gel electrophoresis, comet assay, was performed as a study of the chromosomal aberrations promoted by the compounds on normal cells. Four active and two inactive chalcones were studied in the comet assay against normal human kidney cells (HK-2). A structure-activity relationship analysis of these compounds was performed and for 4- and 3,4-disubstituted derivatives a quantitative correlation was obtained in the case of anti-HT-29 activity.
- Cabrera, Mauricio,Simoens, Macarena,Falchi, Gabriela,Lavaggi, M. Laura,Piro, Oscar E.,Castellano, Eduardo E.,Vidal, Anabel,Azqueta, Amaia,Monge, Antonio,de Cerain, Adela Lopez,Sagrera, Gabriel,Seoane, Gustavo,Cerecetto, Hugo,Gonzalez, Mercedes
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p. 3356 - 3367
(2008/02/07)
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- Structural basis for the activity of the RSK-specific inhibitor, SL0101
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Inappropriate activity of p90 ribosomal S6 kinase (RSK) has been implicated in various human cancers as well as other pathologies. We previously reported the isolation, characterization, and synthesis of the natural product kaempferol 3-O-(3″,4″-di-O-acetyl-α-l-rhamnopyranoside), termed SL0101 [Smith, J. A.; Poteet-Smith, C. E.; Xu, Y.; Errington, T. M.; Hecht, S. M.; Lannigan, D. A. Cancer Res., 2005, 65, 1027-1034: Xu, Y.-M; Smith, J. A.; Lannigan, D. A.; Hecht, S. M. Bioorg. Med. Chem., 2006, 14, 3974-3977: Maloney, D. J.; Hecht, S. M. Org. Lett., 2005, 7, 1097-1099]. SL0101 is a potent and specific inhibitor of RSK; therefore, we performed an analysis of the structural basis for the inhibitory activity of this lead compound. In in vitro kinase assays we found that acylation of the rhamnose moiety and the 4′, 5, and 7-hydroxyl groups are responsible for maintaining a high affinity interaction of RSK with SL0101. It is likely that the hydroxyl groups facilitate RSK binding through their ability to form hydrogen bonds. To determine whether the SL0101 derivatives were specific for inhibition of RSK we analyzed their ability to preferentially inhibit the growth of the human breast cancer line, MCF-7, compared to the normal human breast line, MCF-10A. We have previously validated this differential growth assay as a convenient readout for analyzing the specificity of RSK inhibitors [Smith, J. A.; Maloney, D. J.; Clark, D. E.; Xu, Y.-M.; Hecht, S. M.; Lannigan, D. A. Bioorg. Med. Chem., 2006, 14, 6034-6042]. We found that acylation of the rhamnose moiety was essential for maintaining the selectivity for RSK inhibition in intact cells. Further, the efficacy of SL0101 in intact cells is limited by cellular uptake as well as possible hydrolysis of the acetyl groups on the rhamnose moiety by ubiquitous intracellular esterases. These studies should facilitate the development of a RSK inhibitor, based on the SL0101 pharmacophore, as an anti-cancer chemotherapeutic agent.
- Smith, Jeffrey A.,Maloney, David J.,Hecht, Sidney M.,Lannigan, Deborah A.
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p. 5018 - 5034
(2008/03/12)
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- Synthesis of chalcone analogues with increased antileishmanial activity
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Eighteen analogues of an active natural chalcone were synthesized using xanthoxyline and some derivatives, and these analogues were tested for selective activity against both promastigotes and intracellular amastigotes of Leishmania amazonensis in vitro. Three analogues (10, 12, and 19) containing nitro, fluorine or bromine groups, respectively, displayed increased selective activity against the parasites as compared with the natural chalcone. The nitrosylated chalcone 10 was also tested intralesionally in infected mice and was found to be as effective as Pentostan reference drug at a dose 100 times higher than that of the chalcone in controlling both the lesion growth and the parasite burden.
- Boeck, Paula,Bandeira Falcao, Camila Alves,Leal, Paulo Cesar,Yunes, Rosendo Augusto,Filho, Valdir Cechinel,Torres-Santos, Eduardo Caio,Rossi-Bergmann, Bartira
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p. 1538 - 1545
(2007/10/03)
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- Synthesis of isoflavones containing naturally occurring substitution pattern by oxidative rearrangement of respective flavanones using thallium(III) p-tosylate
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Claisen condensation of substituted 2′-hydroxyacetophenones 1a-c with aromatic aldehydes affords respective substituted 2′-hydroxychalcones 2a-n which on base catalyzed cyclization in pyridine:methanol:water (1:1:1) give respective flavanones 3a-n. The oxidative rearrangement of flavanones with thallium(III) p-tosylate furnishes respective isoflavones 4a-n in overall 62-72% yields starting from 1. The present methodology has been successfully applied for the synthesis of naturally occurring isoflavones such as di-O-methyldaidzein 4a, cabruvin 4b, pseudobabtigenin methylether 4d, 5,7-dimethoxyisoflavone 4f, 5,7,4′-trimethoxyisoflavone 4g, derrustone 4i, 7,8,3′,4′- tetramethoxyisoflavone 41, purpuranin-A 4m and 7,8,3′,4′,5′- pentamethoxyisoflavone 4n and thus the first synthesis of 4n is reported.
- Singh, Om V.,Muthukrishnan,Sunderavadivelu
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p. 2575 - 2581
(2007/10/03)
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- Total synthesis of kaempferol and methylated kaempferol derivatives
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Kaempferol (1), a natural product from various plants, was synthesized in which the longest linear sequence is only seven steps in overall yields of 47% from commercially available 1,3,5-trimethoxybenzene (10). The methylated kaempferols 2-5 were also prepared by use of this concise synthetic methodology. The key transformations in this synthesis involved the I2 oxidative-promoting-cyclization and DDO oxidative hydroxylation. Several strategies to achieve 1 are provided.
- Lee, Yean-Jang,Wu, Tsao-Dong
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p. 201 - 206
(2007/10/03)
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- Anti-ulcer agent comprising chalcone derivative as effective ingredient and novel chalcone derivative
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The present invention relates to an anti-ulcer agent comprising a compound represented by the following general formula I as the effective ingredient, and a novel chalcone derivative included in the compound represented by this general formula I: STR1 wherein X and Y independently stand for a hydrogen atom or together form a single bond, R1 stands for a hydroxyl group, an acetoxy group, a carboxymethoxy group or a methoxycarbonylmethoxy group, R2 stands for a hydrogen atom, an isoprenyl group, isopentyl group or a propyl group, R3 stands for hydroxyl group or a methoxy group, R4 stands for a hydrogen atom, a hydroxyl group or a methoxy group, R5 stands for a hydrogen atom, a hydroxyl group, a methoxy group or an isopentyl group, R6 stands for a hydroxyl group, a methoxy group or a carboxymethoxy group, and R7 stands for a hydrogen atom or a methoxy group.
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- 13C Nuclear Magnetic Resonance Studies on 1,3-Diphenylprop-2-enones
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The 13C NMR spectra of 48 differently substituted chalcones (1,3-diphenylprop-2-enones) have been recorded and the results are discussed.The data will be useful in the identification of new/natural chalcones.
- Parmar, V. S.,Sharma, Sunil,Rathore, J. S.,Garg, Meenu,Gupta, Sandhya,et al.
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p. 470 - 474
(2007/10/02)
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- A highly enantioselective synthesis of (R)- and (S)-5,7-odimethyleucomol
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Both (R)- and (S)-5,7-O-dimethyleucomol 1b (R = Me) were synthesized in 57% overall yield in>96% enantiomeric excess. The key step involves the enantioselective α hydroxylation of the lithium enolate of 8 by readily available (+)- and (-)-[(8,8-dimethoxyc
- Davis, Franklin A.,Chen, Bang-Chi
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p. 6823 - 6826
(2007/10/02)
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- Synthesis of a New Flavone
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The structure of the naturally occuring flavone 5-O-methylacacetin (I) has been confirmed by its synthesis. 5,7-Di-O-methylacacetin has been synthesised.
- Srivastava, Savitri D.,Srivastava, Santosh K.
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