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Some terpolymeric stabilizers based on polymerizable derivatives of 2,4‐dihydroxy‐benzophenone were prepared and evaluated as photostabilizers for rigid poly(vinyl chloride) (PVC). The prepared terpolymers, namely, (methyl methacrylate)/(2‐hydroxyethyl methacrylate)/2‐hydroxy‐4‐methacryloxybenzophenone (MMA/HEMA/HBMA) and (methyl methacrylate)/(2‐hydroxyethyl methacrylate)/2‐hydroxy‐4‐(3‐methacryloxy‐2‐hydroxypropoxy)benzophenone (MMA/HEMA/PBMA), were characterized, and their structures were confirmed by GPC, thermogravimetric analysis, FTIR, and ultraviolet‐visible (UV–vis) spectroscopy. The results revealed that the stabilizing effect of these terpolymers increased upon increasing the stabilizer concentration and the content of UV absorber units in the terpolymers. Promising results were achieved, and the prepared terpolymers showed higher stabilizing efficiency than the corresponding monomeric UV absorbers of low molecular weight. J. VINYL ADDIT. TECHNOL., 2011.© 2011 Society of Plastics Engineers

in Wiley Online Library (wileyonlinelibrary.com).Hexahydroquinolines 1a,b reacted with carbon disulphide in different conditions to yield the corresponding adducts 2a,b and 3a,b. Carrying out the same reactions in acetone as solvent produced the modified new products 4a,b. The interaction of pyrazolopyridine derivatives 5a-d with carbon disulphide under the same previous conditions furnished the isolated products 6a-d, 7a-d, and 8a-d. Studying the behavior of 1a,b or 5a-d toward Lawesson's reagent (LR) formed the final adducts 11a,b or 12a-d. The structure of synthesized compounds was confirmed with the spectroscopic and microanalytical data. The biological activities of 2a, 4a, 4b, 7a, 7c, 8d, 11a, 11b, 12b, and 12c were tested for antimicrobial evaluation.

Certain cytosine-rich (C-rich) DNA sequences can fold into secondary structures as four-stranded i-motifs with hemiprotonated base pairs. Here we synthesized C-rich TINA-intercalating oligonucleotides by inserting a nonnucleotide pyrene moiety between two C-rich regions. The stability of their i-motif structures was studied by using UV melting temperature measurements and circular dichroism spectra at different pH values under noncrowding and crowding conditions (20% poly(ethylene glycol)). When TINA ((R)-3-((4-(1-pyrenylethynyl)benzyl)oxy) propane-1,2-diol) is inserted, the oligonucleotides could form an i-motif at a higher pH than observed for the corresponding wildtype oligonucleotide.

In continuation of our investigation of characteristics and thermodynamic properties of the i‐motif 5′‐d[(CCCTAA)3CCCT)] upon insertion of intercalating nucleotides into the cytosine‐rich oligonucleotide, this article evaluates the stabilities of i‐motif oligonucleotides upon insertion of naphthalimide (1H‐benzo[de]isoquinoline‐1,3(2H)‐dione) as the intercalating nucleic acid. The stabilities of i‐motif structures with inserted naphthalimide intercalating nucleotides were studied using UV melting temperatures (Tm) and circular dichroism spectra at different pH values and conditions (crowding and non‐crowding). This study indicated a positive effect of the naphthalimide intercalating nucleotides on the stabilities of the i‐motif structures compared to the wild‐type structure which is in contrast to a previous observation for a pyrene‐intercalating nucleotide showing a decrease in Tm values.