Novel Bolaamphiphilic Pyrimidinophane As Building Block for Design of Nanosized Supramolecular Systems with Concentration-Dependent Structural Behavior

Abstract

A new macrocyclic bolaamphiphile with thiocytosine fragments in the molecule (B1) has been synthesized and advanced as perspective platform for the design of soft supramolecular systems. Strong concentration-dependent structural behavior is observed in the water-DMF (20% vol) solution of B1 as revealed by methods of tensiometry, conductometry, dynamic light scattering, and atomic force microscopy. Two breakpoints are observed in the surface tension isotherms. The first one, around 0.002 M, is identified as a critical micelle concentration (cmc), whereas the second critical concentration of 0.01 M is a turning point between the two models of the association involved. Large aggregates of ca. 200 nm are mostly formed beyond the cmc, whereas small micelle-like aggregates exist above 0.01 M. The growth of aggregates between these critical points occurs, resulting in a gel-like behavior. An unusual decrease in the solution pH with concentration takes place, which is assumed to originate from the steric hindrance around the B1 head groups. Because of controllable structural behavior, B1 is assumed to be a candidate for the development of biomimetic catalysts, nanocontainers, drug and gene carriers, etc.

Supramolecular Systems Based on Novel Mono‐ and Dicationic Pyrimidinic Amphiphiles and Oligonucleotides: A Self‐Organization and Complexation Study

“…[59] We have suggested a novel class of macrocyclic (pyrimidinophanes) and acyclic bola and gemini amphiphilic nucleotide base derivatives, in particular uracil derivatives, which contain no sugar spacers but labile polymethylene chains with onium groups. [60][61][62][63] These amphiphilic nonglycosidic analogues of nucleotides can possess the advantages of the nucleolipids to form organized systems. Therefore the present work is focused on the self-organization of novel pyrimidinic cationic surfactants and their interactions with the decamer of nucleic acid.…”

Supramolecular systems based on cationic surfactants and amphiphilic macrocycles

“…Specific aggregation behavior is evidently exempli fied by sulfur containing pyrimidinophane PP S (Scheme 3), which demonstrates concentration and temperature dependent gelation [40]. For PP S, an unusual transition from large aggregates to small micellelike particles with increasing solution concen tration was found.…”

“…A number of new dicationic surfactants containing a biofragment, in particular, nucleotide base, uracyl (Scheme 3), was studied in [34][35][36][37][38][39][40][41]. The acyclic and macrocyclic (pyrimidinophanes, PP) analogs were compared, while the macrocycle sizes, positions and lengths of alkyl radicals, and counterion natures were varied.…”

“…In this case, the nature of the head groups is widely varied, in particular, via the functionalization of trimethylammonium (TMA) group with hydroxyalkyl substituents [24][25][26]; incor poration of cyclic and bicyclic fragments [27][28][29]; and variations in the nature of the charged atom, for exam ple, by passing from surfactants of the TMA series to triphenylphosphonium (TPP) derivatives [30]. Among the above listed surfactants, mono and dicationic (gemini) analogs are being investigated [31][32][33] A separate field of research is devoted to mono and dicationic surfactants, which contain "natural" fragments in their molecules, e.g., nucleotide bases, steroid residues, etc., and have various structures, including acyclic and macrocyclic analogs with spac ers of different length and different numbers of hydro phobic fragments [34][35][36][37][38][39][40][41].…”

Amphiphilic Macrocyclic Derivative of Pyrimidine: Self-Assembly, Solubilization and Interaction with DNA Decamer

“…[14] Работы нашего авторского коллектива посвящены систематиче-скому исследованию новых типов амфифилов на макро-циклической платформе, содержащих в своей структуре пиримидиновый фрагмент -пиримидинофанов. В наших ранних работах было показано, что пиримидинофаны обладают рядом уникальных особенностей, в частности, способны к концентрационно зависимому гелеобразова-нию [15] и являются субстрат-специфичными катализато-рами расщепления экотоксикантов различной гидрофоб-ности. [16] Поэтому их дальнейшая модификация и изуче-ние функциональной активности представляет интерес и является актуальным.…”