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Cultivation of energy crops is concerned with estimation of the total lignified biomass (dendromass) production, which is based on the plantation density and individual plant dendromass. The main objective of this study was to investigate the allometry of aboveground leafless biomass of juvenile black poplar hybrids (Populus deltoides x P. nigra ), traditionally used for timber and cellulose production, and to derive generic allometric models for dendromass prediction, relevant to energy crop cultivation in Bulgaria. The study material comprised a variety of growth sites, tree ages and clones, specific to poplar plantings in Bulgaria. We used three principal quantitative predictors: diameter at breast height, total tree height and mean stand (stock) height. The models were not differentiated by clone, because the black poplar hybrids tested were not equally represented in the data, and the inclusion of tree age as a predictor variable seemed unreliable, because of the significant, up to 3 years, variation, which was possible within the narrow age range investigated. We defined the mean stand (stock) height as a composite quantitative variable, which reflected the interaction between the time since planting (age), site quality and the intrinsic growth potential. Stepwise and backward multiple regression analyses were applied to these quantitative variables and their products and sets of adequacy and goodnessof-fit criteria were used to derive individual biomass models for stem and branches. Then we developed compatible additive systems of models for stem, branch and total lignified biomass in log-transformed form. Finally, the prediction data were back-transformed, applying correction for bias, and were cross-validated. Three systems of generic equations were derived to enable flexible model implementation. Equation system M1 proposes a stem biomass model based on tree and stand heights and stem diameter, and a model for branches including mean stand height and breast height diameter; this model displayed the best goodness-of-fit characteristics. Model system M2 uses only the tree height and diameter and therefore is most relevant to dendromass determination in single trees or harvested saplings, while model M3 allows fast and sufficiently accurate biomass estimation of standing poplar stock, because it employs the average stand height and the individual tree diameters. All models are applicable to predict lignified aboveground biomass of juvenile Populus deltoides x P. nigra trees of diameter up to 21 cm and total height up to 16 m.

This article presents a novel formulation for preparation of Lactobacillus casei 01 encapsulated in soy protein isolate and alginate microparticles using spray drying method. A response surface methodology was used to optimise the formulation and the central composite face-centered design was applied to study the effects of critical material attributes and process parameters on viability of the probiotic after microencapsulation and in simulated gastrointestinal conditions. Spherical microparticles were produced in high yield (64 %), narrow size distribution (d50=9.7 µm, span=0.47) and favourable mucoadhesive properties, with viability of the probiotic of 11.67, 10.05, 9.47 and 9.20 log CFU/g after microencapsulation, 3 h in simulated gastric and intestinal conditions and four-month cold storage, respectively. Fourier-transform infrared spectroscopy confirmed the probiotic stability after microencapsulation, while differential scanning calorimetry and thermogravimetry pointed to high thermal stability of the soy protein isolate-alginate microparticles with encapsulated probiotic. These favourable properties of the probiotic microparticles make them suitable for incorporation into functional food or pharmaceutical products.

Herein we report the synthesis of different derivatives of (fluoro)quinolones norfloxacin, ciprofloxacin and pipemidic acid, by incorporating (benzoylamino)methyl on the free nitrogen of the pyperazinyl moiety. The compounds were structurally characterized by 1D and 2D NMR, FTIR and high-resolution mass spectroscopy. In addition, their physicochemical properties were a matter of interest to be correlated with their structure and antimicrobial activity in vitro. Their antimicrobial activities were screened against Gram-positive, Gram-negative bacteria and C. albicans. Higher distribution coefficients and consequently lower water solubility were determined for all synthesized compounds than the ones of the corresponding leading compounds. Inconsequential correlations between the lipophilicity of the compounds and MIC were observed, suggesting that passive diffusion is not the only mechanism for their penetration into bacterial cells. Further studies are needed to determine how substitutions in the (fluoro)quinolone moiety affect the primary target(s), substrate behavior in respect to bacterial transporters and overall bioavailability.

The protonation of ten aliphatic amides in sulfuric acid media was studied by UV spectroscopy. The pKBH+ values and solvation parameters were calculated using Yates and McClelland Method, Excess Acidity Method and Bunnett and Olsen Method. pKBH+ values were –1.44, –1.15, –0.80, –0.32, –1.13 and –0.80 for formamide, dimethylformamide, diethylformamide, diisopropylformamide, diisobutyl­form­amide and dibutylformamide, respectively. According to the pKBH+ values obtained for acetamide, dimethylacetamide, diethylacetamide and diisopropylacetamide (–0.57, –0.29, –0.32 and 0.36, respectively), analogous acetamides were more basic than formamides. Applying the Hammett’s equation, satisfactory correlation could be gained only for some formamides, the basicities of which increased linearly with the inductive effect of the electron donating groups. From Taft’s approach, it can be concluded that the polar effect slightly dominates over the steric one. Excellent correlation between pKBH+ and solvation parameters m* was achieved for formamide, dimethylformamide and diethylformamide. At half- and full-protonation, better correlation was obtained for formamides than for acetamides.

Possible synergistic effect of tamoxifen (2 μM) and hydrazinyldiene-chroman-2,4-diones (10-100 μM) was examined with an aim to create more effective treatment for ER+ breast cancer. Anti-breast cancer effect has been evaluated on the proliferation of MCF-7 breast adenocarcinoma cells using MTT and alamarBlue assays. Cell viability was evaluated after 48h-treatment and the ICs50 of the coumarin derivatives were determined. The apoptotic effect was evaluated by detection of PARP cleavage and reduced activity of the survival kinase Akt. The results demonstrated dose-dependent activity, with a percent of growth inhibition after combination treatment being significantly higher (53% to 79%, 10 μM and 100 μM, respectively) than the one in the cell lines treated with tamoxifen (29% to 37%) and the synthesized coumarin derivatives alone (11% to 68%, 10 μM and 100 μM, respectively). The ICs50 of the synthesized compounds significantly decreased in synergy with tamoxifen (33% to 51%). Coumarin derivative having thiazole moiety with additional methyl groups attached to the carbons at positions 5 and 4 in the thiazole ring showed to be the most potent, with IC50 20 µM when administered alone and 10 µM in synergy with tamoxifen. The levels of phospho-Thr308 Akt were down-regulated by the combination treatment, pointing to tyrosine kinase phosphorylation inhibition. In conclusion, the novel coumarin derivatives enhance the activity of tamoxifen and this combination may be suitable for prevention of ER+ breast cancer or development of related compounds. Further studies are needed to elucidate precisely the type of receptor involved in the activity and the mechanism of action.

This study aims to evaluate the influence of different concentrations of fructooligosaccharide (FOS) as prebiotic on functional and physicochemical properties of Lactobacillus casei loaded chitosan-Ca-alginate microparticles prepared by spray-drying method, after preparation and 6-month storage at 4 °C. Prebiotic compound positively influenced the viability of L. casei during preparation of the microparticles and in storage conditions, while no significant difference of the probiotic viability was observed when different concentrations of FOS in a range of 1.5 - 5% w/w were applied. Having in regard that non-significant improvement in the functional and physicochemical properties of the microparticles with increased content of the FOS was observed, the concentration of 1.5% w/w was recommended as an optimal for preparation of synbiotic loaded microparticles.

An improved synthetic method affording 4-chlorocoumarin-3-sulfonyl chloride (4) in very good yield (ca. 85 %) is reported. This compound was reacted with various bidentate nucleophiles such as 2-aminopyridines and 2-aminothiazoles in order to obtain substituted pyrido- and thiazino-1,2,4-thiadiazino-benzopyranone dioxides (potential anticancer and anti-HIV agents). These reactions occurred rapidly at room temperature giving yellowish precipitates, which are insoluble in common organic solvents, making the purification process challenging. Further investigation has shown that these fused heterocycles are not stable and decompose with opening of the 1,2,4-thiadiazine ring.

We report the synthesis of [(3-chlorobenzamido)methyl]triethylammonium chloride in a reaction of N-(chloromethyl)-3-chlorobenzamide and triethylamine in dry acetone. The structure of the newly synthesized compound was characterized with 1H-NMR, 13C-NMR, FTIR and Mass spectroscopy.

The protonation of some meta and para substituted benzamides in sulfuric acid solutions was studied by UV spectroscopy in the 190–350 nm region. Principal component analysis was applied to separate the effect of protonation from the medium effect. The spectral region 200–350 nm was used for the calculation of the ionization ratio from coefficient of the first principal component, which explains about 95–98 % of the total variability. The dissociation constants as well as the solvation parameters m* and f were calculated using the excess acidity method and the Bunnett–Olsen method. The pKBH+ values obtained with the HA function (defined by the average m* -values) are in satisfactory agreement with those calculated with the previously mentioned methods. The pKBH+ values were correlated with structure using the Hammett (r = – 0.91) and Taft approach. It was found that the inductive effect is more relevant than the resonance one for both substituted benzamides (meta and para).

A variety of benzamidomethyl derivatives were prepared in water under alkaline conditions (pH>9) via reaction of (benzamidomethyl)triethylammonium chloride (1) with different inorganic nucleophiles. Reaction of 1 with hydroxylamine did not give the expected mono(benzamidomethyl)-hydroxylamine (3) but rather gave N,N- di(benzamidomethyl)hydroxylamine (2). Reactions of 1 with sodium azide and potassium cyanide gave benzamidomethyl azide (4a) and benzamidomethyl cyanide (4b) respectively. Potassium thiocyanate and sodium iodide reacted with 1, and the anion- exchanged products (benzamidomethyl)triethylammonium isothiocyanate (5a) and (benzamidomethyl)triethylammonium iodide (5b) were thus obtained. Cyanamide and potassium cyanate reacted readily with 1 and both gave the same mixture of di(benzamidomethyl)amine (7) and tri(benzamidomethyl)amine (8). All the reactions occurred smoothly, under mild conditions, to give the products in moderate to high yields.

We report the synthesis of N-{[(4-nitrophenyl)amino]methyl}benzamide from (benzamidomethyl)triethylammonium chloride and 4-nitroaniline in aqueous media. The structure of the newly synthesized compound was characterized on the basis of 1H-NMR, 13C-NMR and FTIR spectroscopy.

Thiols and amines were benzamidomethylated in water solution at room temperature with (benzamidomethyl)triethylammonium chloride (1) in the presence of a small quantity of triethylamine (pH>9). Benzamidomethyl thioethers (3a-d) and (benzamidomethyl) amines or di(benzamidomethyl)amines (5) were obtained in high yields (>90%) as well as S(CH2NHBz)2 in a reaction of 1 with Na2S. Benzamidomethyl esters RCOOCH2NHBz were obtained (60-75%) in reactions of carboxylic acids with 1 in chloroform or dioxane.

In the title compound, C16H15N3O4, the dihedral angle between the chromane and isoxazole rings [r.m.s. deviations = 0.042 and 0.007 Å, respectively] is 20.33 (12)°. The molecular geometry is stabilized by an intramolecular N—H...O hydrogen bond. In the crystal, N—H...O hydrogen bonds generate chains along the c-axis direction. The crystal studied was a non-morohedral twin.

In this paper, the synthesis and structure of a novel pyrano[3,2-c]coumarin, which was obtained unexpectedly in a reaction of phosphoryl chloride and acenocoumarol, are presented. The chemical structure of the novel compound was elucidated by a detailed spectroscopic analysis based mainly on 1D and 2D NMR techniques. The structure was finally confirmed with a single-crystal X-ray analysis. The B3LYP/6-311+G** method correctly reproduces the bond lengths, bond angles, torsion angles, and other experimental spectroscopic data, which can be useful for investigating the characteristics of some structurally related molecules. Additionally, the title compound was obtained in high yields by performing a dehydratation reaction of acenocuomarol with acetic anhydride.

We report herein the synthesis of 1,1,2,2-tetrakis[(benzoylamino)methyl]-hydrazine from (benzamidomethyl)triethylammonium chloride and hydrazine monohydrate in the presence of triethylamine in ethanol/aqueous media. The structure of the newly synthesized compound was characterized on the basis of 1H-NMR, 13C-NMR, IR and mass spectral data.

(Benzoylamino)methyl 4-acetyloxybenzoate (3) was obtained in a reaction of benzamidomethylation of 4-acetyloxybenzoic acid (2) with (benzamidomethyl)­triethyl­ammonium chloride (1).

A new tribenzamidomethyl hydrazine was synthesized and its IR, 1H NMR, 13C NMR and MS spectroscopic data are presented.

Methylparabene (2) was simply benzamidomethylated with (benzamidomethyl)­triethylammonium chloride (1) in aqueous medium to afford methyl 4-(benzamido­methoxy)benzoate (3) in high yield. The title compound was characterized by elemental analysis, FT-IR, 1H-NMR and 13C-NMR spectroscopy.

In this note, two procedures for the synthesis of (benzoylamino)methyl 4-[(benzoylamino)­methoxy]benzoate (3) are presented. The first procedure is carried out in dioxane/water using benzoylaminomethyl-4-hydroxybenzoate, while the second one employs a suspension of 4-hydroxy­benzoic acid in dioxane. In both procedures, benzamidomethyl triethylammonium chloride is used for the benzamidomethylation reaction.

(Benzoylamino)methyl 4-hydroxybenzoate (“Benzamidomethylparaben”) (3) was obtained from a reaction of 4-hydroxybenzoic acid (2) with a dioxane suspension of (benzamidomethyl)triethylammonium chloride (1). The phenolic group in 2 cannot be benzamidomethylated with 1 in aqueous media.

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