Cycloaddition Reactions Involving Two Heterocyclic Rings. Preparation of Novel Triazolonaphthyridine Ring Systems

A novel class of cycloaddition reactions is described involving the nitrogen atom of a 3-(s-triazol-3-yl) substituent and the 2- or 4- pasition of a pyridinium ring. Structures are confirmed by spectral data

C-Acylation of 2-Methylfuran and Thiophene using N-Acylbenzotriazoles

Reactions of 2-methylfuran and thiophene with readily available N-acylbenzotriazoles (RCOBt, where R = 4-tolyl, 4-methoxyphenyl, benzyl, 4-nitrophenyl, 4-diethylaminophenyl, 2-pyridyl and 1-naphthyl) in the presence of TiCl4 or ZnBr2 produced 2-methyl-4-acylfurans 2a-e and 2-acylthiophenes 3a-f in average yields of 54 % and 75 %, respectively. Literature yields for the preparation of the same compounds are significantly lower

Cycloaddition Reactions Involving Two Heterocyclic Rings. Preparation of Novel Triazolonaphthyridine Ring Systems

A novel class of cycloaddition reactions is described involving the nitrogen atom of a 3-(s-triazol-3-yl) substituent and the 2- or 4- pasition of a pyridinium ring. Structures are confirmed by spectral data

A QSPR Study of Sweetness Potency Using the CODESSA Program

A total of 397 natural and artificial comprehensively referenced sweeteners were classified by their structures into nine sets. The sweetness potencies were correlated with quantum Chemical and other molecular descriptors using the heuristic and the best multi-linear regression methods of the CODESSA software package. QSPR models (two-parameter unless otherwise indicated) emerged for each subclass of sweeteners with R2 values of 0.835 for 47 aldoximes, 0.959 for 8 acesulfamates, 0.919 for 9 sulfamates, 0.941 for 10 α-arylsulfonylalkanoic acids, 0.715 for 27 guanidines (0.802 in a three-parameter correlation), 0.769 for 30 ureas/thioureas (0.888 in a three-parameter correlation), 0.905 for 20 natural sweeteners, 0.957 for 7 miscellaneous sweeteners (one-parameter correlation), 0.688 for 87 peptides (five-parameter correlation). A significant global five-parameter QSPR theoretical model with R2 of 0.686 for the entire set of sweeteners is presented and discussed with reference to the possible existence of single or multiple sweetness receptors

A General Treatment of Solubility 4. Description and Analysis of a PCA Model for Ostwald Solubility Coefficients

Article discussing a general treatment of solubility and a description and analysis of a principal component analysis (PCA) model for Ostwald solubility coefficients

Quantitative Structure–Property Relationship Studies on Ostwald Solubility and Partition Coefficients of Organic Solutes in Ionic Liquids

Article discussing quantitative structure-property relationship studies on Ostwald solubility and partition coefficients of organic solutes in ionic liquids

A General Treatment of Solubility. 3. Principal Component Analysis (PCA) of the Solubilities of Diverse Solutes in Diverse Solvents

Article discussing a general treatment of solubility and principle component analysis (PCA) of the solubilities of diverse solutes in diverse solvents

Lithium and aluminium carbamato derivatives of the utility amide 2, 2, 6, 6- tetramethylpiperidide

Insertion of CO2 into the metal-N bond of a series of synthetically-important alkali-metal TMP (2,2,6,6-tetramethylpiperidide) complexes has been studied. Determined by X-ray crystallography, the molecular structure of the TMEDA-solvated Li derivative shows a central 8-membered (LiOCO)2 ring lying in a chair conformation with distorted tetrahedral lithium centres. While trying to obtain crystals of a THF solvated derivative, a mixed carbonato/carbamato dodecanuclear lithium cluster was formed containing two central (CO3)2- fragments and eight O2CTMP ligands with four distinct bonding modes. A bisalkylaluminium carbamato complex has also been prepared via two different methods (CO2 insertion into a pre-formed Al-N bond and ligand transfer from the corresponding lithium reagent) which adopts a dimeric structure in the solid state