Impact of Geometric Parameters,Charge, and Lipophilicity on Bioactivity of Armed Quinoxaline,Benzothiaole, and Benzothiazine: Pom Analyses of Antibacterial and Antifungal Activity

Abstract

A series of four different armed heterocyclic candidates; 1-(2-methyl-2,3-dihydro-1,3-benzothiazol-2-yl)acetone (2), 1-(3-methyl-4H-1,4-benzothiazin-2-yl)ethanone (3), 2-[(2-aminophenyl)dithio]aniline (4), and 3-hydroxy-3-methyl-4-(3-methyl-2-quinoxalinyl)-2-butanone (5) have been prepared and their microbial activities were evaluated. A correlation of the structure and activities relationships of these compounds with respect to molecular modeling, Lipinski Rule of Five, drug likeness, toxicity profiles, and other physico-chemical properties of drugs are described and verified experimentally.     

A convenient route to diazepines by intramolecular cyclisation of carbonylazides

The appropriate substituted carbonylazides I treated with warm acetic acid give the corresponding acetamide IV or the cyclic lactam VI . This is a convenient route to 10,11-Dihydro-5H-pyrrolo[1,2-a][1,4]-benzodiazepin-11-one and 10,11-Dihydro-4H-thieno[2,3-e]pyrrolo[1,2-a][1,4]diazepin-10-one.     

Synthesis,characterization and coordination chemistry of substituted β-amino dicarbonyls

An efficient and facile method for the synthesis of novel structurally diverse β-amino dicarbonyl compounds is described by exploring the aza-Michael addition reaction in an aqueous medium as a key step. Thereby, 2-(aryl-disubstituted-amino-1-yl-methyl)-malonic acid diethyl esters were achieved in a good to excellent yields. These products were easily isolated with enough purity just by using simple recrystallization. The crystals of the compounds (17) and (24) have been obtained and studied by X-ray crystallographic analyses.     

Methyl 3‐para‐anisyl‐4‐(2‐hydroxy­benzoyl)­isoxazole‐5‐carboxyl­ate

The title compound, C₁₉H₁₅NO₆, contains a planar isoxazole ring. An intramolecular hydrogen bond is formed between the OH group attached to a phenyl ring and a carbonyl O atom.     

Interactions of peptides with metallic cations. I. Complexes glycylglycine–M (M=Li, Na)

In view of better understanding interactions of aminoacids and peptides with metallic cations, in the isolated state and in water, the model system glycylglycine–M⁺ (M=Li, Na) has been studied theoretically. The computations have been performed with the help of the density functional theory (DFT) and the B3LYP functional. The extended basis set was the standard 6-31++G**. In solution we used a recent model of continuum with a multicentric multipole expansion of the charge distribution. Our study shows that low energy complexes with lithium and sodium are rather similar. In the isolated state, the most stable form corresponds to a bidentate complex in which the cation interacts with two oxygen atoms, one from the terminal COOH and one from the amidic carbonyl. In solution, the coordination of the cation in the most stable form is 3, the nitrogen of the end amino group being the third ligand.

The energy range between the lowest energy structure and the highest energy one, in both cases, is slightly reduced under the electrostatic influence of the solvent.     

Interaction of lead atom with atmospheric hydroxyl radical. An ab initio and density functional theory study of the resulting complexes PbOH and HPbO

The two potential hypersurfaces 2A' (ground state) and 2A" (excited state) have been studied through ab initio and density functional theory (DFT) methods for the Pb(OH) complex. Two processes have been identified. The first one concerns the hydrogen inversion process in the coordination of PbOH and the second one the isomerization of PbOH into HPbO. Eight stationary points have been found; four of them correspond to the stable structures with symmetries PbOH(2A'), PbOH(2A"), HPbO(2A'), and HPbO(2Pi), and four correspond to transition states [TS] with the symmetries 2Pi, 2A', 2Sigma+, and 2A". The hydrogen inversion process in PbOH exhibits the so-called Renner-Teller effect with a rather low barrier, whereas the isomerization process PbOH-->HPbO exhibits a rather high barrier. The energetic, structural, spectroscopy, and thermodynamics results obtained at various levels through, e.g., DFT with BLYP, B3LYP exchange-correlation functionals, coupled clusters methods, namely CCSD (single and double excitations) and CCSD(T) (with triple excitations, by perturbation) are presented for the whole sets of the stationary points and their dissociation products. The relativistic effects, as well as spin-orbit interaction, taken into account in the case of the BLYP exchange-correlation functional, have been estimated and discussed in order to measure their importance in the case of system including heavy metals such as Pb. Reactions of lead (Pb) with oxidizing atmospheric molecules (OH, HO2, O2, and O3) have been studied at various levels of approximation in order to study the possible existence of PbOH in the atmosphere.     

Assessing impact force localization by using a particle swarm optimization algorithm

This paper focuses on the inverse problem regarding force localization in the case of impacts not concentrated at a point but which occur on elastic beams. Following the identification approach proposed to solve this problem and which is based on the reciprocity theorem, the impact location characteristics were determined by using particle swarm optimization algorithm. To eliminate numerical trouble due to the trivial solutions appearing in this formulation, the fitness function was customized by introducing a set of weighting coefficients. Four different formulations of the fitness function were considered and their performances with regards to the number of sensors used and their positions were analyzed. They enabled a selection of the best combination of weighting coefficients to be used in the context of an impact force localization process based on the particle swarm optimization technique. Three sensors were found to be required and comparison with a genetic algorithm has revealed the effectiveness of the proposed method in terms of accuracy and computational time.     

Research on nitrogen and sulfur heterocyclic compounds: Synthesis of 10H-pyrrolo[1,2-a]thieno[3,4-e][1,4]-diazepin-5(4H)-one and some derivatives

The synthesis of 10H-pyrrolo[1,2-a]thieno[3,4-e][1,4]diazepin-5(4H)-one ( 16 ) and some derivatives are described from methyl 3-bromomethylthiophene-4-carboxylate ( 5 ). The key step of these sequences is the intramolecular cyclization of the carbonylazides 12 and 13 .     

Réarrangement de thiénobenzothiépinones en thiénoisothiazolinone et benzoisothiazolinone

Under the conditions of the Schmidt reaction the thienobenzothiepinones 1 , 2 and 13 involve a rearrangement respectively in N-benzythieno[2,3-d]isothiazolin-3-one ( 5 ) and benzoisthiazolin-3-one ( 6 ). A mechanism for this rearrangement is proposed.