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.     

CIAT with simultaneous epimerization at two stereocenters. Synthesis of substituted beta-methyl-alpha-homophenylalanines

Diastereoselective aza-Michael additions of phenylethylamine to 3-aroylbutenoic acids are reported. During these processes, efficient control over two new stereogenic centers on the Michael acceptor has been possible via crystallization-induced asymmetric transformation (CIAT). As an application, a convenient two-step synthesis of anti-beta-methylhomophenylalanines is also described.     

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.