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There was no consistent evidence of reproductive toxicity in rats, even at exposure levels which resulted in significantly reduced parental weight gain. In addition, when parental exposure was stopped on GD (gestation day) 20, birth weights as well as postnatal survival were generally similar to control values, even in the 1500 ppm exposure group. Postnatal weight gain was also similar to controls early in weaning, but, if maternal exposure was reinitiated, weight gain was reduced in the high exposure group. However, when exposure was continued until delivery, pups in the high exposure group exhibited reduced litter size, birth weight and poor survival. Thus it was likely that the reduction in fetal weight, seen in the developmental toxicity study in mice, was transient and had no postnatal consequences if maternal exposure was terminated Photodegradation of dissolved organic matter in ice under solar irradiation.The photodegradation behavior of dissolved organic matter (DOM) with different origins in ice under solar irradiation was investigated.<br /><br /> Exposure to sunlight at 22-36% in ice. The naturally occurring DOM had higher photodegradation potentials than the wastewater-derived DOM in ice. Ultraviolet (UV)-absorbing compounds in DOM, regardless of DOM origin, had much higher photodegradation potentials than gross DOC in ice. The susceptibility of UV-absorbing compounds with natural origin to sunlight exposure in ice was higher than those derived from wastewater. Trihalomethane (THM) precursors were more susceptible to photochemical reactions than gross DOC and haloacetic acid (HAA) precursors in ice. THM precursors in naturally occurring DOM were more photoreactive than those in wastewater-derived DOM in ice, while the photoreactivity of HAA precursors in ice was independent of DOM origin. In ice, the photoreactivity of humic-like fluorescent materials, regardless of DOM origin, was higher than that of gross DOC and protein-like fluorescent materials.<br /><br /> DOC reductions caused by sunlight irradiation were found to be negatively correlated to DOC levels, and positively correlated to the aromaticity of DOM. The photodegradation of both wastewater-derived and naturally occurring DOM in ice was significantly facilitated at both acid and alkaline pH, as compared to neutral pH. The photodegradation of DOM in ice, regardless of the origin, was facilitated by nitrate ion [Formula: see text] , nitrite ion [Formula: see text] , ferric ion (Fe(3+)) and ferrous ion (Fe(2+)), and on the other hand, was inhibited by chloridion ion (Cl(-)) and copper ion (Cu(2+)).De Novo Synthesis of Dihydrobenzofurans and Indolines and Its Application to a Modular, Asymmetric Synthesis of Beraprost.Dihydrobenzofurans and indolines are important constituents of pharmaceuticals. Herein, we describe a novel strategy for their construction in which the aromatic ring is created de novo through an inverse-electron demand Diels-Alder reaction and cheletropic extrusion sequence of a 2-halothiophene-1,1-dioxide with an enol ether/enamide, followed by aromatization. Unusually, the aromatization process proved to be highly challenging, but it was discovered that treatment of the halocyclohexadienes with a base effected an α-elimination-aromatization reaction.<br /><br /> Mechanistic investigation of this step using deuterium-labeling studies indicated the intermediacy of a carbene which undergoes a 1,2-hydrogen shift and subsequent aromatization. The methodology was applied to a modular and stereoselective total synthesis of the antiplatelet drug beraprost in only 8 steps from a key enal-lactone. This lactone provided the core of beraprost to which both its sidechains could be appended through a 1,4-conjugate addition process (lower ω-sidechain), followed by de novo construction of beraprost's dihydrobenzofuran (upper α-sidechain) using our newly developed methodology. Additionally, [https://dashing-grape-h1pf36.mystrikingly.com/blog/we-show-selective-hydroxyl-groups-in-the-linear-hrpks-product-are Photo Acid Generator] have demonstrated the breadth of our newly established protocol in the synthesis of functionalized indolines, which occurred with high levels of regiocontrol. According to density-functional theory (DFT) calculations, the high selectivity originates from attractive London dispersion interactions in the TS of the Diels-Alder reaction.N-Heterotriangulenes: Fascinating Relatives of Triphenylamine.Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestrasse 42, D-91054, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestrasse 42, D-91054, Carbonyl- and dimethylmethylene-bridged triphenylamines called N-heterotriangulenes are not only aesthetically pleasing π-conjugated scaffolds interesting on their own but also provide numerous possibilities for further synthetic modifications to serve as versatile precursors for the construction of functional organic molecules.<br /><br /> In this Personal Account we give a historical synopsis depicting the long way from the initial synthesis of N-heterotriangulenes back in the 1970s to their derivatization followed by recent applications in organic electronics.