The Experts below are selected from a list of 2358 Experts worldwide ranked by ideXlab platform
Hermann M Niemeyer - One of the best experts on this subject based on the ideXlab platform.
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Hydroxamic Acids derived from 2 hydroxy 2h 1 4 benzoxazin 3 4h one key defense chemicals of cereals
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Hermann M NiemeyerAbstract:Many cereals accumulate Hydroxamic Acids derived from 2-hydroxy-2H-1,4-benzoxazin-3(4H)-one. These benzoxazinoid Hydroxamic Acids are involved in defense of maize against various lepidopteran pests, most notably the European corn borer, in defense of cereals against various aphid species, and in allelopathy affecting the growth of weeds associated with rye and wheat crops. The role of benzoxazinoid Hydroxamic Acids in defense against fungal infection is less clear and seems to depend on the nature of the interactions at the plant−fungus interface. Efficient use of benzoxazinoid Hydroxamic Acids as resistance factors has been limited by the inability to selectively increase their levels at the plant growth stage and the plant tissues where they are mostly needed for a given pest. Although the biosynthesis of benzoxazinoid Hydroxamic Acids has been elucidated, the genes and mechanisms controlling their differential expression in different plant tissues and along plant ontogeny remain to be unraveled.
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Hydroxamic Acids derived from 2 hydroxy 2h 1 4 benzoxazin 3 4h one key defense chemicals of cereals
Journal of Agricultural and Food Chemistry, 2009Co-Authors: Hermann M NiemeyerAbstract:Many cereals accumulate Hydroxamic Acids derived from 2-hydroxy-2H-1,4-benzoxazin-3(4H)-one. These benzoxazinoid Hydroxamic Acids are involved in defense of maize against various lepidopteran pests...
Bhubaneswar Mandal - One of the best experts on this subject based on the ideXlab platform.
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ethyl 2 cyano 2 4 nitrophenylsulfonyloxyimino acetate mediated lossen rearrangement single pot racemization free synthesis of Hydroxamic Acids and ureas from carboxylic Acids
ChemInform, 2014Co-Authors: Kishore Thalluri, Srinivasa Rao Manne, Dharm Dev, Bhubaneswar MandalAbstract:Ethyl 2-cyano-2-(4-nitrophenylsulfonyloxyimino)acetate (ECN) is employed as a new coupling reagent for the preparation of Hydroxamic Acids and their subsequent Lossen rearrangement into the corresponding isocyanates.
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ethyl 2 cyano 2 4 nitrophenylsulfonyloxyimino acetate mediated lossen rearrangement single pot racemization free synthesis of Hydroxamic Acids and ureas from carboxylic Acids
Journal of Organic Chemistry, 2014Co-Authors: Kishore Thalluri, Srinivasa Rao Manne, Dharm Dev, Bhubaneswar MandalAbstract:Ethyl 2-cyano-2-(4-nitrophenylsulfonyloxyimino)acetate (4-NBsOXY) mediated Lossen rearrangement and its application for the synthesis of ureas is demonstrated. Required Hydroxamic Acids for the Lossen rearrangements were synthesized from carboxylic Acids using the same reagent. Finally, reaction of an amine with the produced isocyanate resulted in urea. Good yields without racemization were achieved under milder and simpler reaction conditions. Reactions are compatible with common N-protecting groups, such as Boc, Fmoc, Cbz, and benzyl, as well as various OH protecting groups, such as tBu and Bzl. Conversion from carboxylic acid to urea is achieved in one pot. Most importantly, byproducts Oxyma [ethyl 2-cyano-2-(hydroxyimino)acetate] and 4-nitrobenzenesulfonic acid can be recovered easily and can be recycled to prepare the reagent. Thus, the method is environmentally friendly and cost-effective.
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Ethyl 2‑Cyano-2-(4-nitrophenylsulfonyloxyimino)acetate-Mediated Lossen Rearrangement: Single-Pot Racemization-Free Synthesis of Hydroxamic Acids and Ureas from Carboxylic Acids
2014Co-Authors: Kishore Thalluri, Srinivasa Rao Manne, Dharm Dev, Bhubaneswar MandalAbstract:Ethyl 2-cyano-2-(4-nitrophenylsulfonyloxyimino)acetate (4-NBsOXY) mediated Lossen rearrangement and its application for the synthesis of ureas is demonstrated. Required Hydroxamic Acids for the Lossen rearrangements were synthesized from carboxylic Acids using the same reagent. Finally, reaction of an amine with the produced isocyanate resulted in urea. Good yields without racemization were achieved under milder and simpler reaction conditions. Reactions are compatible with common N-protecting groups, such as Boc, Fmoc, Cbz, and benzyl, as well as various OH protecting groups, such as tBu and Bzl. Conversion from carboxylic acid to urea is achieved in one pot. Most importantly, byproducts Oxyma [ethyl 2-cyano-2-(hydroxyimino)acetate] and 4-nitrobenzenesulfonic acid can be recovered easily and can be recycled to prepare the reagent. Thus, the method is environmentally friendly and cost-effective
Jiwang Chern - One of the best experts on this subject based on the ideXlab platform.
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quinazolin 2 4 dione based Hydroxamic Acids as selective histone deacetylase 6 inhibitors for treatment of non small cell lung cancer
Journal of Medicinal Chemistry, 2019Co-Authors: Chaowu Yu, Peiyun Hung, Huiting Yang, Yihsun Ho, Yisheng Cheng, Jiwang ChernAbstract:We designed and synthesized quinazolin-2,4-dione-based Hydroxamic Acids to serve as selective competitive inhibitors of histone deacetylase-6 (HDAC6). The most potent and selective compound, 3d (IC50, 4 nM, HDAC6; IC50 > 10 μM, HDAC1), substantially increased acetylation of α-tubulin instead of histones in the lung cancer cell line, LL2. Paclitaxel in combination with 3d had a synergistic anticancer effect on reduction of programmed death-ligand 1 expression in LL/2 cells. When given orally, 3d was mainly found to locate in the liver and lungs, at a concentration 18- to 70-fold greater, respectively, than in plasma. As an orally active HDAC6 inhibitor, 3d (20 mg/kg) potentiated paclitaxel antitumor activity (percentage tumor growth inhibition, 67.5%) in a xenograft syngeneic non-small cell lung cancer mouse model.
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Quinazolin-2,4-dione-Based Hydroxamic Acids as Selective Histone Deacetylase‑6 Inhibitors for Treatment of Non-Small Cell Lung Cancer
2018Co-Authors: Peiyun Hung, Huiting Yang, Yisheng Cheng, Hsing-yi Lai, Jiwang ChernAbstract:We designed and synthesized quinazolin-2,4-dione-based Hydroxamic Acids to serve as selective competitive inhibitors of histone deacetylase-6 (HDAC6). The most potent and selective compound, 3d (IC50, 4 nM, HDAC6; IC50 > 10 μM, HDAC1), substantially increased acetylation of α-tubulin instead of histones in the lung cancer cell line, LL2. Paclitaxel in combination with 3d had a synergistic anticancer effect on reduction of programmed death-ligand 1 expression in LL/2 cells. When given orally, 3d was mainly found to locate in the liver and lungs, at a concentration 18- to 70-fold greater, respectively, than in plasma. As an orally active HDAC6 inhibitor, 3d (20 mg/kg) potentiated paclitaxel antitumor activity (percentage tumor growth inhibition, 67.5%) in a xenograft syngeneic non-small cell lung cancer mouse model
Julia Lloyd - One of the best experts on this subject based on the ideXlab platform.
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identification and optimisation of a series of substituted 5 1h pyrazol 3 yl thiophene 2 Hydroxamic Acids as potent histone deacetylase hdac inhibitors
Bioorganic & Medicinal Chemistry Letters, 2007Co-Authors: Steve Price, Walter Bordogna, Richard James Bull, David E Clark, Peter Crackett, Hazel Joan Dyke, Matthew S Gill, Neil Victor Harris, Julia Gorski, Julia LloydAbstract:Abstract Optimisation of ADS100380, a sub-micromolar HDAC inhibitor identified using a virtual screening approach, led to a series of substituted 5-(1H-pyrazol-3-yl)-thiophene-2-Hydroxamic Acids (6a–i), that possessed significant HDAC inhibitory activity. Subsequent functionalisation of the pendent phenyl group of compounds 6f and 6g provided analogues 6j–w with further enhanced enzyme and anti-proliferative activity. Compound 6j demonstrated efficacy in a mouse xenograft experiment.
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identification and optimisation of a series of substituted 5 pyridin 2 yl thiophene 2 Hydroxamic Acids as potent histone deacetylase hdac inhibitors
Bioorganic & Medicinal Chemistry Letters, 2007Co-Authors: Steve Price, Walter Bordogna, Richard James Bull, David E Clark, Peter Crackett, Hazel Joan Dyke, Matthew S Gill, Neil Victor Harris, Julia Gorski, Julia LloydAbstract:Further investigation of a series of thienyl-based Hydroxamic Acids that included ADS100380 and ADS102550 led to the identification of the 5-pyridin-2-yl-thiophene-2-Hydroxamic acid 3c, which possessed modest HDAC inhibitory activity. Substitution at the 5- and 6-positions of the pyridyl ring of compound 3c provided compounds 5a-g, 7a, b, 9, and 13a. Compound 5b demonstrated improved potency, in vitro DMPK profile, and rat oral bioavailability, compared to ADS102550. Functionalisation of the pendent phenyl group of compounds 5b, 5e and 13a provided analogues that possessed excellent enzyme inhibition and anti-proliferative activity.
Kishore Thalluri - One of the best experts on this subject based on the ideXlab platform.
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ethyl 2 cyano 2 4 nitrophenylsulfonyloxyimino acetate mediated lossen rearrangement single pot racemization free synthesis of Hydroxamic Acids and ureas from carboxylic Acids
ChemInform, 2014Co-Authors: Kishore Thalluri, Srinivasa Rao Manne, Dharm Dev, Bhubaneswar MandalAbstract:Ethyl 2-cyano-2-(4-nitrophenylsulfonyloxyimino)acetate (ECN) is employed as a new coupling reagent for the preparation of Hydroxamic Acids and their subsequent Lossen rearrangement into the corresponding isocyanates.
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ethyl 2 cyano 2 4 nitrophenylsulfonyloxyimino acetate mediated lossen rearrangement single pot racemization free synthesis of Hydroxamic Acids and ureas from carboxylic Acids
Journal of Organic Chemistry, 2014Co-Authors: Kishore Thalluri, Srinivasa Rao Manne, Dharm Dev, Bhubaneswar MandalAbstract:Ethyl 2-cyano-2-(4-nitrophenylsulfonyloxyimino)acetate (4-NBsOXY) mediated Lossen rearrangement and its application for the synthesis of ureas is demonstrated. Required Hydroxamic Acids for the Lossen rearrangements were synthesized from carboxylic Acids using the same reagent. Finally, reaction of an amine with the produced isocyanate resulted in urea. Good yields without racemization were achieved under milder and simpler reaction conditions. Reactions are compatible with common N-protecting groups, such as Boc, Fmoc, Cbz, and benzyl, as well as various OH protecting groups, such as tBu and Bzl. Conversion from carboxylic acid to urea is achieved in one pot. Most importantly, byproducts Oxyma [ethyl 2-cyano-2-(hydroxyimino)acetate] and 4-nitrobenzenesulfonic acid can be recovered easily and can be recycled to prepare the reagent. Thus, the method is environmentally friendly and cost-effective.
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Ethyl 2‑Cyano-2-(4-nitrophenylsulfonyloxyimino)acetate-Mediated Lossen Rearrangement: Single-Pot Racemization-Free Synthesis of Hydroxamic Acids and Ureas from Carboxylic Acids
2014Co-Authors: Kishore Thalluri, Srinivasa Rao Manne, Dharm Dev, Bhubaneswar MandalAbstract:Ethyl 2-cyano-2-(4-nitrophenylsulfonyloxyimino)acetate (4-NBsOXY) mediated Lossen rearrangement and its application for the synthesis of ureas is demonstrated. Required Hydroxamic Acids for the Lossen rearrangements were synthesized from carboxylic Acids using the same reagent. Finally, reaction of an amine with the produced isocyanate resulted in urea. Good yields without racemization were achieved under milder and simpler reaction conditions. Reactions are compatible with common N-protecting groups, such as Boc, Fmoc, Cbz, and benzyl, as well as various OH protecting groups, such as tBu and Bzl. Conversion from carboxylic acid to urea is achieved in one pot. Most importantly, byproducts Oxyma [ethyl 2-cyano-2-(hydroxyimino)acetate] and 4-nitrobenzenesulfonic acid can be recovered easily and can be recycled to prepare the reagent. Thus, the method is environmentally friendly and cost-effective
