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Salts of the weakly coordinating anions [Ga(OTeF5)4]− as well as [Ga(Et)(OTeF5)3]− and the neutral Ga2(Et)3(OTeF5)3 were synthesized and characterized by spectroscopic methods and single‐crystal X‐ray diffraction. Ga2(Et)3(OTeF5)3 was formed by treating GaEt3 with pentafluoroorthotelluric acid (HOTeF5) and reacted with PPh4Cl and CPh3Cl to [PPh4][Ga(Et)(OTeF5)3] and [CPh3][Ga(Et)(OTeF5)3]. In contrast, Ag[Ga(OTeF5)4] was prepared from AgOTeF5 and GaCl3 and was used as a versatile starting material for further reactions. Starting with Ag[Ga(OTeF5)4] the substrates [PPh4][Ga(OTeF5)4] and [CPh3][Ga(OTeF5)4] were formed from PPh4Cl and CPh3Cl. [ABSTRACT FROM AUTHOR]

Salts of the weakly coordinating anions [Ga(OTeF5)4]− as well as [Ga(Et)(OTeF5)3]− and the neutral Ga2(Et)3(OTeF5)3 were synthesized and characterized by spectroscopic methods and single‐crystal X‐ray diffraction. Ga2(Et)3(OTeF5)3 was formed by treating GaEt3 with pentafluoroorthotelluric acid (HOTeF5) and reacted with PPh4Cl and CPh3Cl to [PPh4][Ga(Et)(OTeF5)3] and [CPh3][Ga(Et)(OTeF5)3]. In contrast, Ag[Ga(OTeF5)4] was prepared from AgOTeF5 and GaCl3 and was used as a versatile starting material for further reactions. Starting with Ag[Ga(OTeF5)4] the substrates [PPh4][Ga(OTeF5)4] and [CPh3][Ga(OTeF5)4] were formed from PPh4Cl and CPh3Cl. [ABSTRACT FROM AUTHOR]

Abstract: Hydrocarbons are emitted into the Earth's atmosphere in very large quantities by human and biogenic activities. Their atmospheric oxidation processes almost exclusively yield RO2 radicals as reactive intermediates whose atmospheric fate is not yet fully unraveled. Herein, we show that gas‐phase reactions of two RO2 radicals produce accretion products composed of the carbon backbone of both reactants. The rates for accretion product formation are very high for RO2 radicals bearing functional groups, competing with those of the corresponding reactions with NO and HO2. This pathway, which has not yet been considered in the modelling of atmospheric processes, can be important, or even dominant, for the fate of RO2 radicals in all areas of the atmosphere. Moreover, the vapor pressure of the formed accretion products can be remarkably low, characterizing them as an effective source for the secondary organic aerosol. [ABSTRACT FROM AUTHOR]

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Cadmium is a potent inducer of programmed cell death (PCD) in plants but the morphological changes in cells exposed to cadmium are poorly characterized. Using light and transmission electron microscopy (TEM) we have investigated the changes in ultrastructure of tobacco BY-2 cells treated with 50 µ M CdSO4. The cadmium-induced alterations in cell morphology occurred gradually over a period of 3-4 days and the first stages of the response resembled vacuolar type of cell death. The initial formation of numerous small cytoplasmic vacuoles and dilation of endoplasmic reticulum was followed first by fusion of smaller vacuoles with each other and with big vacuoles, and then by the appearance of autophagic vacuoles containing autophagic bodies. The final stages of cell death were accompanied by necrotic features including loss of plasmalemma integrity, shrinkage of the protoplast and unprocessed cellular components. In addition, we observed a gradual degradation of nuclear material. Our results demonstrate that cadmium-induced plant cell death is a slow process featuring elements of vacuolar cell death and terminating with necrosis. [ABSTRACT FROM AUTHOR]

The character of programmed cell death (PCD) in plants differs in connection with the context, triggering factors and differentiation state of the target cells. To study the interconnections between cell cycle progression and cell death induction, we treated synchronized tobacco BY-2 cells with cadmium ions that represent a general abiotic stressor influencing both dividing and differentiated cells in planta. Cadmium induced massive cell death after application in all stages of the cell cycle; however, both the progression and the forms of the cell death differed pronouncedly. Apoptosis-like PCD induced by cadmium application in the S and G2 was characterized by pronounced internucleosomal DNA fragmentation. In contrast, application of cadmium in M and G1 phases was not accompanied by DNA cleavage, indicating suppression of autolysis and non-programmed character of the death. We interpret these results in the context of the situation in planta, where the induction of apoptosis-like PCD in the S and G2 phase might be connected with a need to preserve genetic integrity of dividing meristematic cells, whereas suppression of PCD response in differentiated cells (situated in G1/G0 phase) might help to avoid death of the whole plant, and thus enable initiation of the recovery and adaptation processes. [ABSTRACT FROM AUTHOR]

Solid phase synthesis (SPS) is well established for the synthesis of biomacromolecules such as peptides, oligonucelotides, and oligosaccharides, and today is also used for the synthesis of synthetic macromolecules and polymers. The key feature of this approach is the stepwise assembly of building blocks on solid support, enabling monodispersity and monomer sequence control. However, in order to achieve such control, a high excess of building blocks is required during the reaction. Herein, the recovery, purification, and reusability of building blocks used in SPS, including representative examples of tailor‐made building blocks, Fmoc‐protected amino acids, and functionalized carbohydrate ligands, are reported for the first time. Results demonstrate the general applicability with recovery in high yields and high purity. Furthermore, the described recovery process can be applied in both manual and automated synthesis using a standard peptide synthesizer. Overall, this process is envisioned to be applicable for a large variety of building blocks used in the SPS of different types of molecules, and to contribute to more resourceful SPS syntheses. [ABSTRACT FROM AUTHOR]