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1. Sensitized Photooxidation of Ortho ‐Prenyl Phenol: Biomimetic Dihydrobenzofuran Synthesis and Total ¹O₂ Quenching ^†

   https://doi.org/10.1111/php.13689  

   Jabeen, Shakeela; Ghosh, Goutam; Lapoot, Lloyd; Durantini, Andrés M.; Greer, Alexander (September 2022, Photochemistry and Photobiology)

   Abstract The sensitized photooxidation ofortho‐prenyl phenol is described with evidence that solvent aproticity favors the formation of a dihydrobenzofuran [2‐(prop‐1‐en‐2‐yl)‐2,3‐dihydrobenzofuran], a moiety commonly found in natural products. Benzene solvent increased the total quenching rate constant (k_T) of singlet oxygen with prenyl phenol by ~10‐fold compared to methanol. A mechanism is proposed with preferential addition of singlet oxygen to prenyl site due to hydrogen bonding with the phenol OH group, which causes a divergence away from the singlet oxygen ‘ene’ reaction toward the dihydrobenzofuran as the major product. The reaction is a mixed photooxidized system since an epoxide arises by a type I sensitized photooxidation. 

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2. Anion Photoelectron Imaging Spectroscopy of C ₆ HF ₅ ^– , C ₆ F ₆ ^– , and the Absence of C ₆ H ₂ F ₄ ^–

   https://doi.org/10.1021/acs.jpca.3c04016  

   McGee, Conor J.; McGinnis, Kristen Rose; Jarrold, Caroline Chick (October 2023, The Journal of Physical Chemistry A)
3. Luminescence and Scintillation of [Nb ₂ O ₂ F ₉ ] ^3– -Dimer-Containing Oxide–Fluorides: Cs ₁₀ (Nb ₂ O ₂ F ₉ ) ₃ F, Cs _9.4 K _0.6 (Nb ₂ O ₂ F ₉ ) ₃ F, and Cs ₁₀ (Nb ₂ O ₂ F ₉ ) ₃ Cl

   https://doi.org/10.1021/acs.inorgchem.1c03787  

   Ayer, Gyanendra B.; Morrison, Gregory; Smith, Mark D.; Jacobsohn, Luiz G.; zur Loye, Hans-Conrad (February 2022, Inorganic Chemistry)
4. Phosphatidylinositol 3, 5‐bisphosphate regulates Ca ²⁺ transport during yeast vacuolar fusion through the Ca ²⁺ ATPase Pmc1

   https://doi.org/10.1111/tra.12736  

   Miner, Gregory E.; Sullivan, Katherine D.; Zhang, Chi; Rivera‐Kohr, David; Guo, Annie; Hurst, Logan R.; Ellis, Ez C.; Starr, Matthew L.; Jones, Brandon C.; Fratti, Rutilio A. (June 2020, Traffic)

   Abstract The transport of Ca²⁺across membranes precedes the fusion and fission of various lipid bilayers. Yeast vacuoles under hyperosmotic stress become fragmented through fission events that requires the release of Ca²⁺stores through the TRP channel Yvc1. This requires the phosphorylation of phosphatidylinositol‐3‐phosphate (PI3P) by the PI3P‐5‐kinase Fab1 to produce transient PI(3,5)P₂pools. Ca²⁺is also released during vacuole fusion upontrans‐SNARE complex assembly, however, its role remains unclear. The effect of PI(3,5)P₂on Ca²⁺flux during fusion was independent of Yvc1. Here, we show that while low levels of PI(3,5)P₂were required for Ca²⁺uptake into the vacuole, increased concentrations abolished Ca²⁺efflux. This was as shown by the addition of exogenous dioctanoyl PI(3,5)P₂or increased endogenous production of by the hyperactivefab1^T2250Amutant. In contrast, the lack of PI(3,5)P₂on vacuoles from the kinase deadfab1^EEEmutant showed delayed and decreased Ca²⁺uptake. The effects of PI(3,5)P₂were linked to the Ca²⁺pump Pmc1, as its deletion rendered vacuoles resistant to the effects of excess PI(3,5)P₂. Experiments with Verapamil inhibited Ca²⁺uptake when added at the start of the assay, while adding it after Ca²⁺had been taken up resulted in the rapid expulsion of Ca²⁺. Vacuoles lacking both Pmc1 and the H⁺/Ca²⁺exchanger Vcx1 lacked the ability to take up Ca²⁺and instead expelled it upon the addition of ATP. Together these data suggest that a balance of efflux and uptake compete during the fusion pathway and that the levels of PI(3,5)P₂can modulate which path predominates. 

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5. Computational protocol for predicting ¹⁹F NMR chemical shifts for PFAS and connection to PFAS structure

   https://doi.org/10.1002/jcc.26939  

   Mifkovic, Maleigh; Pauling, Jessica; Vyas, Shubham (June 2022, Journal of Computational Chemistry)

   Abstract Per‐ and polyfluoroalkyl substances (PFAS) are robust “forever” chemicals that have become global environmental contaminants due to their inability to degrade using traditional techniques. In addition to the persistent nature of PFAS, the structural and functional diversity in PFAS creates a unique challenge in identification and remediation. Their identification is further complicated by the absence of standards for many PFAS. This work is aimed at developing a protocol for computing and establishing accurate¹⁹F NMR chemical shifts for PFAS using density functional theory (DFT), which can aid in the identification of PFAS. The impact of solvation and basis sets was evaluated by comparing the computed data with the experimental measurements. Results showed the addition of dispersion corrections in the methodology improve the accuracy of calculated NMR parameters within 4 ppm of the experimental values. Adding a second diffuse function and additional polarization did not improve the accuracy, likely because of the electronegativity of fluorine which does not allow the electron density of fluorine atoms to be polarized. The inclusion of various implicit solvation (DMSO, chloroform, and water) yielded negligible differences in accuracy, and were overall less accurate than the gas phase calculations. The most accurate methodology was then applied to more environmentally relevant PFAS, and the impact of helical nature on the NMR signatures was evaluated. The implication of this work is to be able to improve the identification of structurally diverse PFAS using the¹⁹F NMR. 

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