1.Green approach to stereoselective synthesis of benzo[d]chromeno[3,4- h]oxathiazonine derivatives via MCRs in water: a combined experimental and DFT study.
Djahaniani H1, Fatemi F, Ektefa F, Mohtat B, Notash B. Comb Chem High Throughput Screen. 2015;18(10):990-9.
(7S, 14S, 16R)- dialkyl 6-oxo-6,7,13,14-tetrahydro-7,14-methanobenzo[d]chromeno[3,4- h][1,6,3]oxathiazo-nine-14,16-dicarboxylates 4 and (S)-methyl 2-(2-methoxy-2-oxoethyl)-2,3- dihydrobenzo[d]thiazole-2-carboxylates 5 were readily synthesized in a ratio 3:1 and moderated yield by multicomponent reactions of 4-hydroxycoumarin and acetylenic esters with benzothiazole without using a catalyst. Also, The GIAO/DFT approach at the B3LYP/6-31G** level of theory was used to calculate the (1)H, (15)N, (17)O and (13)C NMR chemical shifts of product 4b. These computations are performed on the basis of X-ray structural data which are collected at 120(2) K temperature. In order to take into account intermolecular hydrogen bonds and the van der Waals effects, two different sizes of clusters (two model of trimeric and pentameric clusters) have been considered. A comparison between the experimental (Exp.) and calculated (Cal.) (1)H and (13)C NMR chemical shifts may reveal that the solution contains monomer, trimer1, trimer2, and pentamer models.
2.Arginase-2 is cooperatively up-regulated by nitric oxide and histone deacetylase inhibition in human umbilical artery endothelial cells.
Krause BJ1, Hernandez C2, Caniuguir A2, Vasquez-Devaud P2, Carrasco-Wong I2, Uauy R3, Casanello P4. Biochem Pharmacol. 2016 Jan 1;99:53-9. doi: 10.1016/j.bcp.2015.10.018. Epub 2015 Nov 10.
Arginase-2 counteracts endothelial nitric oxide synthase (eNOS) activity in human endothelium, and its expression is negatively controlled by histone deacetylase (HDAC2). Conversely NO inhibits HDAC and previous studies suggest that arginase-2 is up-regulated by NO. We studied whether NO regulates arginase-2 expression in umbilical artery endothelial cells (HUAEC) increasing ARG2 promoter accessibility. HUAEC exposed to NOC-18 (NO donor, 1-100μM, 0-24h) showed an increase in arginase-2 but a decrease in eNOS mRNA levels in a time-dependent manner, with a maximal effect at 100μM (24h). Conversely NOS inhibition with L-NAME (100μM) reduced arginase-2 mRNA and protein levels, an effect reverted by co-incubation with NOC-18. Treatment with TSA paralleled the effects of NO on arginase-2 and eNOS at mRNA and protein levels, with maximal effect at 10μM. Co-incubation of NOC-18 (100μM) with a sub-maximal concentration of TSA (1μM) potentiated the increase in arginase-2 mRNA levels, whilst L-NAME prevented TSA-dependent arginase-2 induction.
3.Systemic acquired resistance activation in solanaceous crops as a management strategy against root-knot nematodes.
Molinari S1. Pest Manag Sci. 2016 May;72(5):888-96. doi: 10.1002/ps.4063. Epub 2015 Jul 14.
BACKGROUND: Activators of systemic acquired resistance (SAR), such as salicylic acid (SA) and its synthetic functional analogues benzo(1,2,3)thiadiazole-7-carbothionic acid-S-methyl ester (BTH) and 2,6-dichloroisonicotinic acid (INA), were tested on tomato, eggplant and pepper for the control of the root-knot nematode Meloidogyne incognita. Effects on plant fitness, nematode reproduction and root galling were screened in relation to different methods of application, to different applied dosages of chemicals and to different plant growth stages. Dosages applied to plants were in relation to plant weights. These chemicals were also tested for their possible nematotoxic activity in vitro.
4.Effect of volatile organic compounds from bacteria on nematodes.
Xu YY1, Lu H1, Wang X1, Zhang KQ2, Li GH3. Chem Biodivers. 2015 Sep;12(9):1415-21. doi: 10.1002/cbdv.201400342.
The five studied bacterial strains could produce volatile organic compounds (VOCs) that kill nematodes. Based on their 16S rRNA sequences, these strains were identified as Pseudochrobactrum saccharolyticum, Wautersiella falsenii, Proteus hauseri, Arthrobacter nicotianae, and Achromobacter xylosoxidans. The bacterial VOCs were extracted using solid-phase micro-extraction (SPME) and subsequently identified by GC/MS analysis. The VOCs covered a wide range of aldehydes, ketones, alkyls, alcohols, alkenes, esters, alkynes, acids, ethers, as well as heterocyclic and phenolic compounds. Among the 53 VOCs identified, 19 candidates, produced by different bacteria, were selected to test their nematicidal activity (NA) against Caenorhabditis elegans and Meloidogyne incognita. The seven compounds with the highest NAs were acetophenone, S-methyl thiobutyrate, dimethyl disulfide, ethyl 3,3-dimethylacrylate, nonan-2-one, 1-methoxy-4-methylbenzene, and butyl isovalerate.