Sulfonamide and amide derivatives of tris(aminoethyl)amine (TREN) are known to facilitate phospholipid translocation across vesicle and erythrocyte membranes; that is, they act as synthetic translocases. In this report, a number of new TREN-based translocases are evaluated for their abilities to bind phosphatidylcholine and translocate a fluorescent phosphatidylcholine probe. Association consta...

A comparative research has been developed for acidity and stability constants of M(TTA) and M(Asp) complexes which have been determined by potentiometric pH titration. Depending on metal ion–binding properties, vital differences in building complex were observed. The present study shows that in M(TTA) complexes, metal ions are coordinated to the carboxyl groups, but in M(Asp) some metal ions ar...

To address the question of concerted versus a stepwise reaction mechanisms for the cyclization of the 2-hydroxypropyl aryl and alkyl RNA models (1a-k) promoted by dinuclear Zn(II) complex (4) at (s)spH 9.8 and 25 degrees C, the non-cleavable O-hydroxypropyl phenylphosphonate analogues 6a and 6b were subjected to the catalytic reaction in methanol. These phosphonates did not undergo isomerizatio...

Contents 1. Introduction 2. Soil acidity and its indices 2.1. Actual acidity. 2.2. Potential acidity. 2.3. Cation (positive ion) exchange capacity and saturation with bases. 3. Natural reasons for increasing soil acidification 3.1. Leaching regime. 3.2. Soil-forming rocks and plants. 3.3. The distribution of acid soils. 4. The reasons for anthropogenic acidification of soils. The phenomenon of ...

Commercial 0.9% saline solution for infusion has a pH around 5.5. There are many reasons for this acidity, some of them still obscure. It is also true that infusion of normal saline can lead to metabolic acidaemia, yet the link between the acidity of saline solution and the acidaemia it can engender is not straightforward. This commentary draws together the known and putative sources of acidity...

Density Functional Theory is situated within the evolution of Quantum Chemistry as a facilitator of computations and a provider of new, chemical insights. The importance of the latter branch of DFT, conceptual DFT is highlighted following Parr's dictum "to calculate a molecule is not to understand it". An overview is given of the most important reactivity descriptors and the principles they are...

Soil pH, soil acidity, and their effects on plants The pH scale, ranging from 0 to 14, is used to indicate acidity and alkalinity. pH is a measure of the concentration of hydrogen ions (symbol = H) in the water contained in the soil. A pH of 7.0 is neutral, values below 7 are acidic, and those above 7 are alkaline (basic). The lower the pH, the more acid the soil. Each unit pH drop indicates te...

Hadacidin 2 und seine Monoalkalisalze 3 wurden nach Literaturangaben dargestellt. Das nach 1. c. 1 gewonnene Produkt muß jedoch durch Extraktion mit siedendem Äther und nachfolgende Umfällung mit Chloroform/Petroläther (1 : 4) aus Acetonlösung gereinigt werden. Die IR-Spektren wurden mit Infrarotspektrometern IR-10 (4000 — 300 c m 1 , KBr-Preßlinge) und IR-11 (700 — 33 c m 1 , Nujolaufschlämmun...