- Novel fluorinated 7-hydroxycoumarin derivatives containing an oxime ether moiety: Design, synthesis, crystal structure and biological evaluation
-
A series of fluorinated 7-hydroxycoumarin derivatives containing an oxime ether moiety have been designed, synthesized and evaluated for their antifungal activity. All the target compounds were determined by1H-NMR,13C-NMR, FTIR and HR-MS spectra. The single-crystal structures of compounds 4e, 4h, 5h and 6c were further confirmed using X-ray diffraction. The antifungal activities against Botrytis cinerea (B. cinerea), Alternaria solani (A. solani), Gibberella zeae (G. zeae), Rhizoctorzia solani (R. solani), Colletotrichum orbiculare (C. orbiculare) and Alternaria alternata (A. alternata) were evaluated in vitro. The preliminary bioassays showed that some of the designed compounds displayed the promising antifungal activities against the above tested fungi. Strikingly, the target compounds 5f and 6h exhibited outstanding antifungal activity against B. cinerea at 100 μg/mL, with the corresponding inhibition rates reached 90.1 and 85.0%, which were better than the positive control Osthole (83.6%) and Azoxystrobin (46.5%). The compound 5f was identified as the promising fungicide candidate against B. cinerea with the EC50 values of 5.75 μg/mL, which was obviously better than Osthole (33.20 μg/mL) and Azoxystrobin (64.95 μg/mL). Meanwhile, the compound 5f showed remarkable antifungal activities against R. solani with the EC50 values of 28.96 μg/mL, which was better than Osthole (67.18 μg/mL) and equivalent to Azoxystrobin (21.34 μg/mL). The results provide a significant foundation for the search of novel fluorinated 7-hydroxycoumarin derivatives with good antifungal activity.
- Dai, Peng,Jiao, Jian,Wang, Qing-Qing,Zhang, Shu-Guang,Zhang, Wei-Hua
-
-
- A general method for fluorescent labeling of the N-termini of lanthipeptides and its application to visualize their cellular localization
-
Labeling of natural products with biophysical probes has greatly contributed to investigations of their modes of action and has provided tools for visualization of their targets. A general challenge is the availability of a suitable functional group for chemoselective modification. We demonstrate here that an N-terminal ketone is readily introduced into various lanthipeptides by the generation of a cryptic N-terminal dehydro amino acid by the cognate biosynthetic enzymes. Spontaneous hydrolysis of the N-terminal enamines results in α-ketoamides that site-specifically react with an aminooxy-derivatized alkyne or fluorophore. The methodology was successfully applied to prochlorosins 1.7 and 2.8, as well as the lantibiotics lacticin 481, haloduracin α, and haloduracin β. The fluorescently modified lantibiotics were added to bacteria, and their cellular localization was visualized by confocal fluorescence microscopy. Lacticin 481 and haloduracin α localized predominantly at sites of new and old cell division as well as in punctate patterns along the long axis of rod-shaped bacilli, similar to the localization of lipid II. On the other hand, haloduracin β was localized nonspecifically in the absence of haloduracin α, but formed specific patterns when coadministered with haloduracin α. Using two-color labeling, colocalization of both components of the two-component lantibiotic haloduracin was demonstrated. These data with living cells supports a model in which the α component recognizes lipid II and then recruits the β-component.
- Bindman, Noah A.,Van Der Donk, Wilfred A.
-
supporting information
p. 10362 - 10371
(2013/08/23)
-
- N-ALKOXYAMIDES OF 6-(TRISUBSTITUTED PHENYL)-4-AMINOPICOLINATES AND THEIR USE AS SELECTIVE HERBICIDES FOR CROPS
-
N-Alkoxyamides of 4-aminopicolinic acids and 6-amino-4-pyrimidinecarboxylates are selective herbicides for corn, canola and sugar beet.
- -
-
Page/Page column 4-5
(2010/09/07)
-
- Design and synthesis of m1-selective muscarinic agonists: (R)-(-)-(Z)- 1-azabicyclo[2.2.1]heptan-3-one, O-(3-(3'-methoxyphenyl)-2-propynyl)-oxime maleate (CI-1017), a functionally m1-selective muscarinic agonist
-
The synthesis and SAR of a series of (Z)-(±)-1- azabicyclo[2.2.1]heptan-3-one, O-(3-aryl-2-propynyl)oximes are described. The biochemistry and pharmacology of 24Z (PD 142505) and its enantiomers are highlighted. 24Z is functionally an m1-selective muscari
- Tecle, Halle,Barrett, Stephen D.,Lauffer, David J.,Augelli-Szafran, Corinne,Brann, Mark R.,Callahan, Michael J.,Caprathe, Bradley W.,Davis, Robert E.,Doyle, Patricia D.,Eubanks, David,Lipiniski, William,Mirzadegan, Tara,Moos, Walter H.,Moreland,Nelson, Carrie B.,Pavia, Michael R.,Raby, Charlotte,Schwarz, Roy D.,Spencer, Carolyn J.,Thomas, Anthony J.,Jaen, Juan C.
-
p. 2524 - 2536
(2007/10/03)
-
- Synthesis and pharmacological characterization of O-alkynyloximes of tropinone and N-methylpiperidinone as muscarinic agonists
-
A number of O-alkynyloximes of tropinone and N-methyl-4-piperidinone have been synthesized and evaluated for muscarinic activity. The affinities of these oximes were tested in homogenates of cerebral cortex, heart, and submandibulary glands from rats using [3H]pirenzepine and [3H]-N- methylscopolamine as radioligands. The oximes bind to the cortical muscarinic receptors with pK(i) values varying from 3 to 7. Higher binding affinities were observed for the O-alkynyl tropinone oximes than the corresponding piperidinone analogues. Binding to the muscarinic sites in the heart and submandibulary glands was also observed but with lower affinities. Good M1 subtype selectivity (10-fold or greater) was observed with some oximes (26a, 28a, 32a) at the cortical sites. These oximes also attenuated scopolamine- induced impairment of the water mask task in mice. Functional assays for M3 activity on the rat aorta showed that all oximes possessed M3 agonist action but M2 agonist activity was not observed at the endothelium-denuded rabbit aorta. Analysis of the quantitative structure-activity relationship (QSAR) indicated that the Connolly surface area is an important determinant of activity, accounting for 70% of the variation in cortical binding affinity among the oximes.
- Xu, Rong,Sim, Meng-Kwoon,Go, Mei-Lin
-
p. 3220 - 3231
(2007/10/03)
-