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The novel hydrogensquarate salt of 1,10-phenanthroline has been synthesized, isolated and structurally elucidated by single crystal X-ray diffraction. 1,10-Phenanthrolinium hydrogensquarate monohydrate (1) crystallizes in the non-centrosymmetric P21 space group. Its hydrogensquarate anions form a stable dimer by means of (Sq)OH⋯O＝C(Sq) hydrogen bonds with lengths of 2.509, 2.526, 2.510, and 2.524 Å. The solvent water molecule interacts with the anion dimers by means of strong and moderate hydrogen bonds HOH⋯O＝C(Sq) with bond lengths of 2.782 and 2.845 Å, respectively. The 1,10-phenanthrolinium cation participates in NH⋯OH2 interactions with the water molecule (bond lengths of 2.810, 2.758, 2.779 and 2.760 Å). Surprisingly, compound contains four independent molecules in the unit cell. Optical properties were elucidated by means of linear-polarized solid-state IR-spectroscopy and UV-spectroscopy. In addition TGA, DSC, DTA data, positive and negative ESI mass spectra as well as 1H- and 13C NMR spectra are presented. Quantum chemical methods were used to calculate the electronic structure, vibrational data and electronic spectra as well as non-linear optical properties of neutral 1,10-phenanthroline and its protonated cation. Second harmonic generation measurements of the novel compound demonstrate that the compound possesses effective d coefficients of 1.9 ± 0.5 pm V−1, value that is about three times higher that of the low temperature form of potassium dideuterophosphate. [Copyright &y& Elsevier]

The actual business conditions which are featured with great number of changes in the social and political system in the Republic of Macedonia have their impact in all the spheres of the social life, including the accounting-management profession. The fact that "the modern management is not compatible with obsolete accounting" is very often emphasized. As it is natural, the management accounting should be adjusted to the management needs. Starting with this statement, the research subject of this study will be the process of implementation and efficient functioning of the management accounting in the companies and organizations in the Republic of Macedonia, taking into consideration their impact on the success of the companies and their functioning. On the other hand, the scientific-empirical goal, on the basis of empirical research, is completely focused on the ways of implementing of the management accounting as one kind of contemporary approach of the managers in the organizations by the means of high management, undercovering completely the possibilities for efficient implementation and application of the management accounting concept in the Macedonian organizations.

The 'digital plumber' is a conceptualisation in ubicomp research that describes the work of installing and maintaining IoT devices. But an important and often understated element of commercial IoT solutions is their long-term socio-technical infrastructural nature, and therefore long-term installation and maintenance needs. This adds complexity to both the practice of digital plumbing and to the work of design that supports it. In this paper we study a commercial company producing and installing IoT alarm systems. We examine video recordings that capture how a digital plumbing representative and software development team members make changes to both the installation process and supporting technology. Our data enables us to critically reflect on concepts of infrastructuring, and uncover the ways in which the team methodically foreground hidden elements of the infrastructure to address a point of failure experienced during field trials of a new version of their product. The contributions from this paper are twofold. Firstly, our findings build on previous examples of infrastructuring in practice by demonstrating the use of notions of elemental states to support design reasoning through the continual foregrounding and assessment of tensions identified as key factors at the point of failure. Secondly, we build on current notions of digital plumbing work. We argue that additional responsibilities of 'reporting failure' and 'facilitation of change' are part of the professional digital plumbing role and that commercial teams should support these additional responsibilities through collaborative troubleshooting and design sessions alongside solid communication channels with related stakeholders within the product team., Competing Interests: Conflict of InterestsThe authors declare that they have no conflict of interest., (© The Author(s) 2023.)

Previously we reported the results from an effort to improve Gram-negative antibacterial activity in the oxazolidinone class of antibiotics via a systematic medicinal chemistry campaign focused entirely on C-ring modifications. In that series we set about testing if the efflux and permeation barriers intrinsic to the outer membrane of Escherichia coli could be rationally overcome by designing analogs to reside in specific property limits associated with Gram-negative activity: i) low MW (<400), ii) high polarity (clogD 7.4 <1), and iii) zwitterionic character at pH 7.4. Indeed, we observed that only analogs residing within these limits were able to overcome these barriers. Herein we report the results from a parallel effort where we explored structural changes throughout all three rings in the scaffold for the same purpose. Compounds were tested against a diagnostic MIC panel of Escherichia coli and Staphylococcus aureus strains to determine the impact of combining structural modifications in overcoming the OM barriers and in bridging the potency gap between the species. The results demonstrated that distributing the charge-carrying moieties across two rings was also beneficial for avoidance of the outer membrane barriers. Importantly, analysis of the structure-permeation relationship (SPR) obtained from this and the prior study indicated that in addition to MW, polarity, and zwitterionic character, having ≤4 rotatable bonds is also associated with evasion of the OM barriers. These combined results provide the medicinal chemist with a framework and strategy for overcoming the OM barriers in GNB in antibacterial drug discovery efforts., (Copyright © 2017. Published by Elsevier Ltd.)

Novel antibacterials with activity against the Gram-negative bacteria associated with nosocomial infections, including Escherichia coli and other Enterobacteriaceae, are urgently needed due to the increasing prevalence of multidrug-resistant strains. A major obstacle that has stalled progress on nearly all small-molecule classes with potential for activity against these species has been achieving sufficient whole-cell activity, a difficult challenge due to the formidable outer membrane and efflux barriers intrinsic to these species. Using a set of compound design principles derived from available information relating physicochemical properties to Gram-negative entry or activity, we synthesized and evaluated a focused library of oxazolidinone analogues, a currently narrow spectrum class of antibacterials active only against Gram-positive bacteria. In this series, we have explored the effectiveness for improving Gram-negative activity by identifying and combining beneficial structural modifications in the C-ring region. We have found polar and/or charge-carrying modifications that, when combined in hybrid C-ring analogues, appear to largely overcome the efflux and/or permeability barriers, resulting in improved Gram-negative activity. In particular, those analogues least effected by efflux and the permeation barrier had significant zwitterionic character.

The three new Au (III), Pt (II) and Pd (II) complexes with pentapeptide glycyl-glycyl-(L)-methyonyl-glycyl-glycine have been synthesized, isolated, and spectroscopically and structurally elucidated in solution and in the solid-state. Solid-state linear-dichroic infrared (IR-LD) spectroscopy of oriented colloids in a nematic liquid crystal host, (1)H- and (13)C-NMR, TGA and DSC, UV-VIS spectroscopy, EPR, ESI- and FAB- mass spectrometry and HPLC tandem mass spectrometry (HPLC-MS/MS) have been used. Quantum chemical calculations and molecular modelling were carried out in order to determine the structures and spectroscopic properties of the ligand, the newly synthesised metal complexes and their interactions with calf thymus DNA. The pentapeptide coordinates in a tetradentate manner with the metal ions via an S-atom on the methyonyl-side chain, two N-amide nitrogens, (after a deprotonation of gly(1) and gly(2) residues) and the primary NH(2) nitrogen of N(termini). The MN(3)S chromophores are distorted to near square planar geometry. Their interaction with calf thymus DNA shows the competitive N7 (G) coordination position, where the pentapeptide residues is coordinated with the metal centers in a tridentate manner through the S-atom and both N-amide centers. This interaction leads to a transfer from a distorted square planar geometry (D(4h) symmetry) to a pseudo tetrahedral (T(d) symmetry) of the metal ions with the obtained dihedral angle values of the MN(3)N7(G) chromophors within 114.67 degrees to 110.92 degrees . The isolated Au (III) complex is stable for about 1.5 months, while the stability of the Au (III) complex/DNA adduct is decreased to 33 days.

Method of linear polarized vibrational (both IR- and Raman) spectroscopy of oriented colloids in nematic host is applied on N-acetyl-L-cysteine, L-cysteine, L-cystine and L-ascorbic acid with a view to obtain experimental bands assignment and local structural elucidation in solid-state. Structural results are compared with available crystallographic data for all of the systems studied. Scopes and limitations of the polarized method are shown. Discussion on the correlation between polarized spectroscopic data and the space group type as well as the number of the molecules in the unit cell (Z) is performed. Compounds with monoclinic space group P2(1), containing Z = 1 (N-acetyl-L-cysteine) and 2 (L-cysteine and L-ascorbic acid) are elucidated. One of the rare for organic molecules, hexagonal P6(1)22 space group and Z = 6 (L: -cystine) is also elucidated. Experimental assignment of the characteristics frequencies is obtained, explaining the typical for the crystals Fermi-resonance, Fermy-Davydov and Davydov splitting effects. For first time in the literature we are reported the orientation of the solid-mixture in nematic host, using the trade product ACC (Hexal, Germany), containing mainly N-acetyl-L-cysteine and L-ascorbic acid. Quantitative IR-spectroscopic approach for determination of solid mixtures is presented as well. The intensity ratio between 1,716 cm(-1) (characteristic for N-acetyl-L-cysteine) and 990 cm(-1), (attributed N-acethyl-cysteine and vitamin C) is used. Linear regression analysis between content and the peak ratio data for ten solid-binary mixtures, leads to straight-line plot y = 1.08(2) (+/-0.04(9)) + (-0.11(4) +/- 0.01(1))x, where x = 1/X ( i ). Factor r of 0.9641 and a reliability of 98.85% are obtained. The analysis of ACC 200 (Hexal, Germany) show that the IR measurements leads to standard deviation of 0.010 and 0.011 at P about 0.0500 for the systems and a confidence of >98.77(1)%.

This mini review deals with the modern aspects of the spectroscopy and structural elucidation of amino acid derivatives and small biologically active compounds. Free peptide bond rotation in these systems yields various conformers, which possess differing biological activities. Another phenomenon is the intermolecular or intramolecular stacking observed in aromatic small peptides. Specifically, the main aim is to illustrate the successful application of the "complex tool", consisting of a combination of the theoretical approximation methods with experimental linear polarized infrared (IR-LD) and/or Raman spectroscopy of oriented colloid suspensions in a nematic host. The possibilities and limitations of the approach for detailed vibrational assignment and structural elucidation of small peptides are discussed. Having in mind that physical and chemical properties of these systems can be precisely calculated by means of ab initio and DFT methods at Hartee-Fock, MP2 and B3LYP level of theory, varying basis sets, the results obtained allow a precise assignment of many vibrational bands to the corresponding normal modes, electronic structures and conformational state. The validity of the conclusions about the structure or vibrational properties of these systems have been supported, compared and/or additionally proved by the results from independent physical methods. In this respect (1)H and (13)C-NMR, single crystal X-ray diffraction, HPLC tandem mass spectrometry as well as thermal methods are all employed. A well ordered crystal must first be grown in order to determine the molecular structure by the absolute method of single crystal X-ray diffraction. Although the 3D structures of peptides have been determined over the past decades, peptide crystallization is still a major obstacle to X-ray diffraction work, the presence of chiral centre/s makes for this difficulty. For this reason the "complex tool" presented can be regarded as an alternative method for obtaining of structural information in the solid-state. It is obviously that only absolute crystallographic method can yield geometric parameters, bond lengths and angles, but the spectroscopic method presented can provide information about the dihedral angles for cis- and trans-configurated amide groups, mutual disposition of the aromatic fragments in peptides. Its validity is illustrated by comparing the theoretical and spectroscopic results obtained with available crystallographic data. The mini review can serve as a useful source of information not only for specialists in IR spectroscopy but, also, for other scientists, working in the field of structural analysis of amino acid derivatives and other small biologically active systems.

The novel chloride salt of 1-butyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridine (1), has been synthesized as the tetrahydrate and its structure and properties elucidated in detail spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and mass spectrometry. Quantum chemical calculations were performed with a view to supporting and explaining the experimental structural and spectroscopic data. The compound (1) crystallizes in triclinic P1 space group and its unit cell contains two independent 1-butyl-4-[2-(3,5-dimethoxy4-hydroxyphenyl)ethenyl)]pyridinium] cations, differing with respect to the butyl chain torsion angle for which values of 80.0(9) degrees and 173.6(3) degrees are observed. The cations and anions are joined into infinite layers, formed by two different dimers and including solvent molecules. Hydrogen bonds OH...OH(2) (2.814 A), HOH...O(CH(3)) (2.960 A), OH...Cl (2.967 A), HOH...Cl(-) (3.034, 3.188, 3.161 and 3.062 A) and HOH...OH(2) (2.772 A) are observed. For first time in the literature, we are reporting the crystal structure of the dye with the syring-fragment in the molecule. The spectroscopic properties of the novel compound are compared and with those of the corresponding quinoide form (2). Both the forms (1) and (2) are characterized by 21 and 140 nm solvatochromic effects depending of the type of the solvent. The UV-spectroscopic data in solution confirm the formation of classical H-aggregates in polar protic solvent mixture.

The correlation between the structure and the spectroscopic properties of N-methylcodeinium iodide (1) has been studied, using the methods of single crystal X-ray diffraction, IR-LD spectroscopy of oriented samples as a suspension in nematic liquid crystals, UV-vis spectroscopy and 1H and 13C NMR spectroscopy. HPLC tandem mass spectrometry (HPLC ESI MS/MS) and thermal methods were also employed. Quantum chemical calculations have been performed with a view to obtaining the electronic structure and vibrational properties of the title compound. Compound (1) crystallizes in the space group P2(1)2(1)2(1) and its cations and anions are joined by moderate intermolecular OH...I- interaction of length 3.442A. The codeine molecule exhibits the classical T-shape for opiates. A dihedral angle value of 86.4(5) degrees between the A/B/C and D/E planes is obtained. Rings A and B are effectively coplanar with an interplanar angle of 3.6(3) degrees.

Two novel hydrogensquarates of 3-nicotinoyl (1) and 3-isonicotinoyl (2) coumarin have been synthesized and their structures and properties elucidated spectroscopically and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and electronic spectra. The IR-spectroscopic elucidation is carried out by a comparison with the characteristics of corresponding neutral 3-nicotinoyl and 3-isonicotinoyl coumarins.

The IR-spectroscopic properties of three esters of 1-coumarinylbenzylphosphonic acid are elucidated both in solution and in solid-state. Linear-polarized IR-spectroscopy of oriented colloid suspensions in nematic host is used for experimental IR-characteristic band assignment in solid-state. Theoretical quantum chemical DFT calculations at B3LYP level of theory and 6-31++G** basis set are carried. Theoretical electronic structure and vibrational properties of compounds studied are discussed.

By means of IR-LD spectroscopy of oriented as suspension in nematic liquid crystal solids, a detailed IR-bands assignment and a stereo-structural prediction of codeine, codeinone and N-norcodeine have been carried out. The data are compared with known crystallographic ones of codeine and codeinone obtained by single crystal X-ray diffraction.

A flow injection on-line sorption system was developed for the separation and preconcentration of traces of Ag, Cd, Co, Ni, Pb, U and Y from natural water samples with subsequent detection by ICP TOF MS. Simultaneous preconcentration of the analytes was achieved by complexation with the chelating reagent 1-phenyl-3-methyl-4-benzoylpyrazol-5-one immobilized on the inner walls of a (200cm x 0.5mm) PTFE knotted reactor. The analytes were eluted and transported to an axial ICP TOF MS system with 1% (v/v) HNO(3) containing 0.3microg l(-1) of Rh as an internal standard using ultrasonic nebulization. The detection limits (3sigma) varied from 0.3ng l(-1) for Y to 15.2ngl(-1) for Ni and the precision (R.S.D.) was better than 4%. Using a loading time of 90s and a sample flow rate of 4.5ml min(-1), enhancement factors of 3-14 were obtained for the different analytes in comparison with their direct determination by ICP TOF MS with ultrasonic nebulization without preconcentration. The accuracy of the method was demonstrated by analysis of water based certified reference materials.