p-Hydroxybenzoic Acid-Urea-Formaldehyde Copolymers and Their Ion-Exchange Properties

Copolymers (PUF) were synthesized by the condensation of p-hydroxybenzoic acid (P), urea (U), and formaldehyde (F), in the presence of different acidic catalysts and using varied molar ratios of reacting monomers. One of the copolymers having the highest molecular weight was fractionated. Copolymer compositions have been determined on the basis of their elemental analysis and conductometric titrations in the nonaqueous phase. Molecular weights (M_n) have been estimated by VPO. Copolymer prepared by using the stoichiometric properties of the monomers and HCI as catalyst furnished the highest molecular weight (M_n). The viscosity measurements carried out in DMF indicate normal behavior. TGA and DSC data were analyzed to compare the relative thermal stability and estimate the characteristic parameters. IR spectra were studied to elucidate the structure. Chelation ion-exchange properties have also been studied employing the batch equilibration method. The order of selectivity of metal ions by the copolymers is UO₂ ²⁺ > Fe³⁺ >Cu²⁺ > Co²⁺.     

Polymers Derived from 4-Substituted Salicylic Acids as Antifungal Agents

4-Amino-, chloro-, and bromo-substituted salicylic acid-formaldehyde polymers and their metal chelates were screened for their antifungal activity. Various copolymers prepared from 4-chloro-(bromo)salicylic acid, formaldehyde, and other comonomers were also screened for their antifungal activity. All these polymers, copolymers, and polychelates were found active against several fungi Their fungicidal activities are compared with those of the corresponding monomers and monomeric chelates.     

Magnetic,Spectral, Thermal,and Electrical Properties of Coordination Polymers Derived from Terpolymers

Coordination polymers of Cu(II), Ni(II), Co(II), zinc(II), chromium(IU), iron(IU), oxovanadium(N), and dioxouranium-(VI) with p-hydroxybenzoic acid (PHB)-thiourea (T)-trioxane (T) (PHBTT) polymer were prepared. The analytical data agree with 1:1 metal-ligand stoichiometry. Magnetic susceptibility, visible and IR spectra, and thermal and electrical conductivities of the chelates have been studied and probable structures assigned to the chelates.     

Effect of Chain Length of Polyethylene Glycol and Crosslink Density (NCO/OH) on Properties of Castor Oil Based Polyurethane Elastomers

The equilibrium swelling study of polyurethanes (PU) was carried out in various solvents in order to calculate their solubility parameter. The kinetics of swelling and sorption have also been studied in 1,4‐dioxane at 30°C. The PU was synthesized by reacting a novel polyol (castor oil derivative and epoxy based resin, EpxR) and one of the polyethylene glycols (PEG 200, PEG 400, PEG 600) with different weight compositions, with a toluene diisocyanate (TDI) adduct (derived from toluene diisocyanate and R60 polyol). Different NCO/OH ratio viz. 1, 1.3 and 1.7 were employed in the study. The results were found to vary with the weight composition of polyol components, as well as the crosslink density of the samples. The sorption behavior is also found to vary with the molecular weight of polyethylene glycol employed in the preparations of the polyurethanes. Kinetic studies of swelling revealed that the sorption is anomalous in nature. The diffusion coefficient (D) increased with an increase in the NCO/OH ratio and decreased with an increase in chain length of polyethylene glycol. The sorption coefficient (S) decreased with an increase in crosslink density (NCO/OH) and increased with increasing polyethylene glycol (i.e., PEG 200, PEG 400, and PEG 600) moieties in the polyurethanes. The molecular weight between two crosslink points was calculated using the Flory Rehner equation (24), and hence, the number of chains per unit volume (N) and degree of crosslinking (ν) in all the samples were determined.     

Synthesis and Study of Polymeric Ultraviolet Absorbers. II

Polymeric UV absorbers have been prepared by free-radical solution copolymerization at 75°C of methyl methacrylate and 2-hydroxy-4-methacryloyloxybenzophenone monomers at low conversion (around 10%). The composition of the copolymers was determined by UV, IR, and NMR studies. The molecular weight was estimated by GPC. The reactivity ratios were determined by several methods. Viscosity was used to study the effect of copolymer composition and solvents. The copolymers were also analyzed by TGA and DSC, and DSC was used to study the effect of copolymer composition on T_g.     

ToxML,a data exchange standard with content controlled vocabulary used to build better (Q)SAR models

Development of accurate quantitative structure–activity relationship (QSAR) models requires the availability of high quality validated data. International regulations such as REACH in Europe will now accept (Q)SAR-based evaluations for risk assessment. The number of toxicity datasets available for those wishing to share knowledge, or to use for data mining and modelling, is continually expanding. The challenge is the current use of a multitude of different data formats. The issues of comparing or combining disparate data apply both to public and proprietary sources. The ToxML project addresses the need for a common data exchange standard that allows the representation and communication of these data in a well-structured electronic format. It is an open standard based on Extensible Markup Language (XML). Supporting information for overall toxicity endpoint data can be included within ToxML files. This makes it possible to assess the quality and detail of the data used in a model. The data file model allows the aggregation of experimental data to the compound level in the detail needed to support (Q)SAR work. The standard is published on a website together with tools to view, edit and download it.     

CoMFA and CoMSIA studies on C-aryl glucoside SGLT2 inhibitors as potential anti-diabetic agents

SGLT2 has become a target of therapeutic interest in diabetes research. CoMFA and CoMSIA studies were performed on C-aryl glucoside SGLT2 inhibitors (180 analogues) as potential anti-diabetic agents. Three different alignment strategies were used for the compounds. The best CoMFA and CoMSIA models were obtained by means of Distill rigid body alignment of training and test sets, and found statistically significant with cross-validated coefficients (q ²) of 0.602 and 0.618, respectively, and conventional coefficients (r ²) of 0.905 and 0.902, respectively. Both models were validated by a test set of 36 compounds giving satisfactory predicted correlation coefficients (r ² _pred) of 0.622 and 0.584 for CoMFA and CoMSIA models, respectively. A comparison was made with earlier 3D QSAR study on SGLT2 inhibitors, which shows that our 3D QSAR models are better than earlier models to predict good inhibitory activity. CoMFA and CoMSIA models generated in this work can provide useful information to design new compounds and helped in prediction of activity prior to synthesis.     

Synthesis and Biological Activity of 3-[4H-(1,2,4)-Triazolyl]-2,6-diaryl-1,3,5-oxadiazine-4-thione

4-Amino-1,2,4-triazole (1) undergoes facile condensation with aromatic aldehydes to afford the corresponding 4-(arylidene-amino)-4H-[1,2,4]-triazole (2a–h) in good yield. Rearrangement of compounds (2a–h) with benzoyl isothiocyanate/4-chloro-benzoyl isothiocyanate/2,4-dichloro-benzoyl isothiocyanate yields corresponding 1,3,5-oxadiazine derivatives (3). Structural elucidation of these compounds was based on elementary analysis and spectral data studies. The newly synthesized compounds were evaluated for their antibacterial activities.     

Synthesis,method optimization,anticancer activity of 2,3,7-trisubstituted Quinazoline derivatives and targeting EGFR-tyrosine kinase by rational approach: 1st Cancer Update

A novel 3-(substituted benzylideneamino)-7-chloro-2-phenyl quinazoline-4(3H)-one (7–27) has been synthesized and characterised by IR, ¹H NMR, ¹³C NMR spectroscopy, and elemental analysis. We changed the methodology for the synthesis of 3-amino 7-chloro-2-phenyl quinazolin-4(3H)-one 6 to fusion reaction at 250 °C, instead of using solvent, to avoid the problem of ring opening, which is commonly observed while synthesizing quinazolines from benzoxazinone. NCI selected, 7-chloro-3-{[(4-chlorophenyl) methylidene] amino}-2-phenylquinazolin-4(3H)-one 12, with GI₅₀ value of ?5.59 M, TGI value of ?5.12 M, and LC₅₀ value of ?4.40 M showed remarkable activity against CNS SNB-75 Cancer cell line. Rational approach and QSAR techniques enabled the understanding of the pharmacophoric requirement for 2,3,7-tri substituted quinazoline derivatives to inhibit EGFR-tyrosine kinase as antitumor agents and could be used as an excellent framework in this field that may lead to discovery of potent anti tumor agent.