1878-85-9Relevant academic research and scientific papers
New Multidentate Compounds of Ether-Ester Type
Lin, Whei Oh,de Souza, Maria C. Bastos Viera,Altoe, Antonio P.,Alt, Helmut G.
, p. 359 - 364 (1983)
A series of ether-esters containing multidentate components have been prepared from phenoxyacetic acid.The ligands were synthesized from the appropriate phenoxyacetic acid chloride and various alcohols.Four types of new compounds have been obtained. - Keywords: Acyclic crown compounds; Ester-ether crown compounds; Multidentate ligands; Phenoxyacetic acid ester
Polycarboxylated compounds and compositions containing same
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Page/Page column 22-23, (2021/06/09)
Methods of selectively modifying lignin, polycarboxylated products thereof, and methods of deriving aromatic compounds therefrom. The methods comprise electrochemically oxidizing lignin using stable nitroxyl radicals to selectively oxidize primary hydroxyls on β-O-4 phenylpropanoid units to corresponding carboxylic acids while leaving the secondary hydroxyls unchanged. The oxidation results in polycarboxylated lignin in the form of a polymeric β-hydroxy acid. The polymeric β-hydroxy acid has a high loading of carboxylic acid and can be isolated in acid form, deprotonated, and/or converted to a salt. The β-hydroxy acid, anion, or salt can also be subjected to acidolysis to generate various aromatic monomers or oligomers. The initial oxidation of lignin to the polycarboxylated form renders the lignin more susceptible to acidolysis and thereby enhances the yield of aromatic monomers and oligomers obtained through acidolysis.
Modulation of DNA damage response by targeting ATM kinase using newly synthesized di-phenoxy acetamide (DPA) analogs to induce anti-neoplasia
Al-Ostoot, Fares Hezam,Sherapura, Ankith,Malojirao, Vikas H.,Thirusangu, Prabhu,Al-Muhimeed, Tahani I.,Khanum, Shaukath Ara,Prabhakar
, p. 1344 - 1360 (2021/06/14)
Background: Imbalance and instability in the structure of the DNA have become major characteristics of cancer. In response to DNA damage, DNA damage response (DDR) protein, ataxia telangiectasia mutated (ATM), plays a pivotal role in the modulation of regulatory regions responsible for inhibition of apoptosis, thereby neoplastic progression. Methods: A new series of DPA (7a–t) were synthesized, characterized. Anti-proliferative studies to identify the lead compound were carried out by LDH and MTT assay. Apoptosis/DNA damage was measured through FACS, Annexin-v staining, TUNEL and Comet assay. Elucidation of molecular mechanism through immunoblot and further validation of the drug effect through in vivo approaches. Results: Initial in vitro anti-proliferative screening of Compounds DPA (7a–t) against multiple cancer cell lines identified Compound DPA (7n) as a potent cytotoxic molecule with IC50 value of 4.3?μM. Down the line, in vitro and in vivo evaluation of Compound DPA (7n) inferred that it has apoptotic inducing potentiality. Further, evaluation of molecular mechanism inferred that Compound DPA (7n) effectively modulates ATM phosphorylation only, eventually altering downstream signalling pathways. Conclusions: Compound DPA (7n) emerged as a potent proapoptotic and anti-neoplastic agent by inhibiting ATM kinase activity both in vitro and in vivo. The conferring results ascertain that the drug could be developed as a new ATM kinase inhibitor with anti-cancer capacity. Graphic abstract: [Figure not available: see fulltext.]
Targeting HIF-1α by newly synthesized Indolephenoxyacetamide (IPA) analogs to induce anti-angiogenesis-mediated solid tumor suppression
Al-Ostoot, Fares Hezam,Sherapura, Ankith,V, Vigneshwaran,Basappa, Giridhara,H.K, Vivek,B.T, Prabhakar,Khanum, Shaukath Ara
, p. 1328 - 1343 (2021/05/03)
Background: Hypoxic microenvironment is a common feature of solid tumors, which leads to the promotion of cancer. The transcription factor, HIF-1α, expressed under hypoxic conditions stimulates tumor angiogenesis, favoring HIF-1α as a promising anticancer agent. On the other hand, synthetic Indolephenoxyacetamide derivatives are known for their pharmacological potentiality. With this background here, we have synthesized, characterized, and validated the new IPA (8a–n) analogs for anti-tumor activity. Methods: The new series of IPA (8a–n) were synthesized through a multi-step reaction sequence and characterized based on the different spectroscopic analysis FT-IR, 1H, 13C NMR, mass spectra, and elemental analyses. Cell-based screening of IPA (8a–n) was assessed by MTT assay. Anti-angiogenic efficacy of IPA (8k) validated through CAM, Rat corneal, tube formation and migration assay. The underlying molecular mechanism is validated through zymogram and IB studies. The in vivo anti-tumor activity was measured in the DLA solid tumor model. Results: Screening for anti-proliferative studies inferred, IPA (8k) is a lead molecule with an IC50 value of ?5?μM. Anti-angiogenic assays revealed the angiopreventive activity through inhibition of HIF-1α and modulation downstream regulatory genes, VEGF, MMPs, and P53. The results are confirmative in an in vivo solid tumor model. Conclusion: The IPA (8k) is a potent anti-proliferative molecule with anti-angiogenic activity and specifically targets HIF1α, thereby modulates its downstream regulatory genes both in vitro and in vivo. The study provides scope for new target-specific drug development against HIF-1α for the treatment of solid tumors. Graphic abstract: [Figure not available: see fulltext.].
Electrochemical Aminoxyl-Mediated Oxidation of Primary Alcohols in Lignin to Carboxylic Acids: Polymer Modification and Depolymerization
Rafiee, Mohammad,Alherech, Manar,Karlen, Steven D.,Stahl, Shannon S.
supporting information, p. 15266 - 15276 (2019/10/19)
An electrochemical process has been developed for chemoselective oxidation of primary alcohols in lignin to the corresponding carboxylic acids. The electrochemical oxidation reactions proceed under mildly basic conditions and employ 2,2,6,6-tetramethyl-1-piperidine N-oxyl (TEMPO) and 4-acetamidoO (ACT) as catalytic mediators. Lignin model compounds and related alcohols are used to conduct structure-reactivity studies that provide insights into the origin of the reaction selectivity. The method is applied to the oxidation of lignin extracted from poplar wood chips via a mild acidolysis method, and the reaction affords a novel polyelectrolyte material. Gel permeation chromatography data for the oxidized lignin shows that this material has a molecular weight and molecular weight distribution very similar to that of the extracted lignin, but notable differences are also evident. Base titration reveals a significant increase in the acid content, and the oxidized lignin has much higher water solubility relative to the extracted lignin. Treatment of the oxidized lignin under acidic conditions results in depolymerization of the material into characterized aromatic monomers in nearly 30 wt% yield.
Design and Synthesis of Novel 4-Hydroxyl-3-(2-phenoxyacetyl)-pyran-2-one Derivatives for Use as Herbicides and Evaluation of Their Mode of Action
Lei, Kang,Li, Pan,Yang, Xue-Fang,Wang, Shi-Ben,Wang, Xue-Kun,Hua, Xue-Wen,Sun, Bin,Ji, Lu-Sha,Xu, Xiao-Hua
, p. 10489 - 10497 (2019/10/02)
In order to develop a novel herbicide containing the β-triketone motif, a series of 4-hydroxyl-3-(2-phenoxyacetyl)-pyran-2-one derivatives were designed and synthesized. The bioassay results showed that compound II15 had good pre-emergent herbicidal activity even at a dosage of 187.5 g ha-1. Moreover, compound II15 showed a broader spectrum of weed control when compared with a commercial herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), and displayed good crop safety to Triticum aestivum L. and Zea mays Linn. when applied at 375 g ha-1 under pre-emergence conditions, which indicated its great potential as a herbicide. More importantly, studying the molecular mode of action of compound II15 revealed that the novel triketone structure is a proherbicide of its corresponding phenoxyacetic acid auxin herbicide, which has a herbicidal mechanism similar to that of 2,4-D. The present work indicates that the 4-hydroxyl-3-(2-phenoxyacetyl)-pyran-2-one motif may be a potential lead structure for further development of novel auxin-type herbicides.
Ketoreductase catalyzed stereoselective bioreduction of α-nitro ketones
Wang, Zexu,Wu, Xiaofan,Li, Zhining,Huang, Zedu,Chen, Fener
supporting information, p. 3575 - 3580 (2019/04/14)
We report here the stereoselective bioreduction of α-nitro ketones catalyzed by ketoreductases (KREDs) with publicly known sequences. YGL039w and RasADH/SyADH were able to reduce 23 class I substrates (1-aryl-2-nitro-1-ethanone (1)) and ten class II substrates (1-aryloxy-3-nitro-2-propanone (4)) to furnish both enantiomers of the corresponding β-nitro alcohols, with good-to-excellent conversions (up to >99%) and enantioselectivities (up to >99% ee) being achieved in most cases. To the best of our knowledge, KRED-mediated reduction of class II α-nitro ketones (1-aryloxy-3-nitro-2-propanone (4)) is unprecedented. Select β-nitro alcohols, including the synthetic intermediates of bioactive molecules (R)-tembamide, (S)-tembamide, (S)-moprolol, (S)-toliprolol and (S)-propanolol, were stereoselectively synthesized in preparative scale with 42% to 90% isolated yields, showcasing the practical potential of our developed system in organic synthesis. Finally, the advantage of using KREDs with known sequence was demonstrated by whole-cell catalysis, in which β-nitro alcohol (R)-2k, the key synthetic intermediate of hypoglycemic natural product (R)-tembamide, was produced in a space-time yield of 178 g L?1 d?1 as well as 95% ee by employing the whole cells of a recombinant E. coli strain coexpressing RasADH and glucose dehydrogenase as the biocatalyst.
Iridium-catalysed primary alcohol oxidation and hydrogen shuttling for the depolymerisation of lignin
Lancefield, Christopher S.,Teunissen, Lucas W.,Weckhuysen, Bert M.,Bruijnincx, Pieter C. A.
supporting information, p. 3214 - 3221 (2018/07/31)
Lignin is a potentially abundant renewable resource for the production of aromatic chemicals, however its selective depolymerisation is challenging. Here, we report a new catalytic system for the depolymerisation of lignin to novel, non-phenolic monoaromatic products based on the selective β-O-4 primary alcohol dehydrogenation with a Cp?Ir-bipyridonate catalyst complex under basic conditions. We show that this system is capable of promoting the depolymerisation of model compounds and isolated lignins via a sequence of selective primary alcohol dehydrogenation, retro-aldol (Cα-Cβ) bond cleavage and in situ stabilisation of the aldehyde products by transfer (de)hydrogenation to alcohols and carboxylic acids. This method was found to give good to excellent yields of cleavage products with both etherified and free-phenolic lignin model compounds and could be applied to real lignin to generate a range of novel non-phenolic monomers including diols and di-acids. We additionally show, by using the same catalyst in a convergent, one-pot procedure, that these products can be selectively channelled towards a single di-acid product, giving much simpler product mixtures as a result.
Isoflavone amide derivatives, their preparation method and medical use
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Paragraph 0077, (2017/08/31)
The invention belongs to the field of medicinal chemistry, and relates to derivatives of isoflavones amides, as well as a preparation method and medical application of derivatives, in particular to the derivatives of the isoflavones amides with the general formula of (I) shown as the specification, the preparation method and the medical application of the derivatives, particularly the application of the derivatives of the isoflavones amides serving as medicaments for preventing or treating hyperlipemia, adiposis or type-II diabetes.
Discovery of benzofuran-3(2H)-one derivatives as novel DRAK2 inhibitors that protect islet β-cells from apoptosis
Wang, Sheng,Xu, Lei,Lu, Yu-Ting,Liu, Yu-Fei,Han, Bing,Liu, Ting,Tang, Jie,Li, Jia,Wu, Jiangping,Li, Jing-Ya,Yu, Li-Fang,Yang, Fan
, p. 195 - 208 (2017/03/02)
Death-associated protein kinase-related apoptosis-inducing kinase-2 (DRAK2) is a serine/threonine kinase that plays a key role in a wide variety of cell death signaling pathways. Inhibition of DRAK2 was found to efficiently protect islet β-cells from apoptosis and hence DRAK2 inhibitors represent a promising therapeutic strategy for the treatment of diabetes. Only very few chemical entities targeting DRAK2 are currently known. We carried out a high throughput screening and identified compound 4 as a moderate DRAK2 inhibitor with an IC50value of 3.15?μM. Subsequent SAR studies of hit compound 4 led to the development of novel benzofuran-3(2H)-one series of DRAK2 inhibitors with improved potency and favorable selectivity profiles against 26 selected kinases. Importantly, most potent compounds 40 (IC50?=?0.33?μM) and 41 (IC50?=?0.25?μM) were found to protect islet β-cells from apoptosis in dose-dependent manners. These data support the notion that small molecule inhibitors of DRAK2 represents a promising strategy for the treatment of diabetes.
