The protective effects against drought stress of the endophytic bacterium Bacillus subtilis 10-4 were measured by studying the priming response in two wheat (Triticum aestivum L.)—Ekada70 (E70) and Salavat Yulaev (SY)—lines, tolerant and susceptible to drought, respectively. B. subtilis 10-4 improved germination and growth parameters under normal conditions in both cultivars with the most pronounced effect observed in cv. E70. Under drought conditions, B. subtilis 10-4 significantly ameliorated the negative impact of stress on germination and growth of cv. E70, but had no protective effect on cv. SY. B. subtilis 10-4 induced an increase in the levels of photosynthetic chlorophyll (Chl) a, Chl b, and carotenoids (Car) in the leaves of cv. E70, both under normal and drought conditions. In cv. SY plants, bacterial inoculation decreased the contents of Chl a, Chl b, and Car under normal conditions, but pigment content were almost recovered under drought stress. B. subtilis 10-4 increased water holding capacity (WHC) of cv. E70 (but did not affect this parameter in cv. SY) and prevented the stress-induced decline in WHC in both cultivars. Notably, B. subtilis 10-4 increased endogenous salicylic acid (SA) concentration in both cultivars, especially in cv. E70. Moreover, B. subtilis 10-4 reduced drought-induced endogenous SA accumulation, which was correlated with the influence of endophyte on growth, indicating a possible involvement of endogenous SA in the implementation of B. subtilis-mediated effects in both cultivars. Overall, B. subtilis 10-4 inoculation was found to increase drought tolerance in seedlings of both cultivars, as evidenced by decreased lipid peroxidation, proline content, and electrolyte leakage from tissues of wheat seedlings primed with B. subtilis 10-4 under drought conditions.

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A comprehensive analysis of solutions of 5‐fluorouracil (5FU) in water and an organic medium (dimethylsulfoxide, DMSO) was carried out using quantum chemical methods and nuclear magnetic resonance (NMR) spectroscopy. The details of anionic form generation in the solution of 5FU with an equimolar amount of potassium hydroxide were studied by 13С, 1Н, 15N and 19F NMR. Interpretation of NMR spectral data was carried out using quantum chemical calculations at the TPSSTPSS/6‐311+G(d,p) level of theory. Specific solvation of 5FU and 1THF‐5FU was modeled in approximation using the five‐water cluster model and solvate complex including two DMSO molecules. It was established that in an alkaline medium in DMSO 5FU occurred mainly as a type of an anion with a deprotonation on N(1) position of a pyrimidine ring whereas in water alkaline solution—as a mixture of two anions with a deprotonation on N(1) and N(3) positions with a predominant content of the latter form. For the quantitative definition of the deprotonation forms of 5FU the technique based on the data of theoretical and experimental NMR 13C spectroscopy, tested on a model compound 1‐(tetrahydrofuranyl‐2)‐5‐fluoro‐pyrimidinedione‐2,4 (tegafur, THF‐5FU), was offered. The N(3) anion was found from spectral data to be more thermodynamically stable than the N(1) anion by 2.40 kJ mol−1 (calculated value 2.24 kJ mol−1) in an alkaline–water solution. Both alkaline–water and alkaline–DMSO solutions of THF‐5FU (THF‐5FU/KOH = 1/1) were characterized by the ratio of the equilibrium concentrations of the anion and diketo‐tautomer as 9:1 and 4.3:1, respectively. Copyright © 2014 John Wiley & Sons, Ltd.

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Potentially useful 17-, and 22÷25-membered macrolides containing azine or hydrazide groups were synthesized from tetrahydropyran via [1+1]-condensation at room temperature of 7-oxooctyl-7-oxooctanoate, which was obtained via Tishchenko reaction from 7-oxooctanal, with hydrazine hydrate and hydrazides of several dicarboxylic acids.Polyfunctional macroheterocycles with interesting complexing properties and biological activity are widely used as interphase-transfer catalysts, extractants, analytical reagents, and materials for creating ion-selective electrodes [1-3].Herein we report the synthesis of 17-(9), 22-(10), 23- (11), 24- (12), and 25-membered (13) macrolides that may exhibit complexing properties and biological activity and contain azine or hydrazide functional groups. The synthetic scheme is based on chemo-and regioselective transformations of a ketoalcohol (2) that is accessible in three steps from tetrahydropyran (1) [4]. Corey oxidation of 2 produced ketoaldehyde 3, which has been used to synthesize 9-oxo-2E-decenoic acid (multifunctional pheromone of honeybee Apis mellifera L.) [5], and small quantities (up to 15%) of 7-oxooctyl-7-oxooctanoate (4) by disproportionation of 3 via a Tishchenko reaction. The yield of 4 could be increased (up to 70%) by using the classical method [6] with catalytic quantities of aluminium triisopropoxide.[1+1]-Condensation of 4 in dioxane at high dilution and room temperature with hydrazine hydrate or dihydrazides of malonic (5), succinic (6), glutaric (7), and adipic (8) acids and subsequent successive work up of the reaction mixture with CH 2 Cl 2 and hexane (1:10 ratio) produced in good yields (40-50%) macrolides with azine (9) or hydrazide (10-13) groups, respectively.