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Imine‐linked covalent organic frameworks (COFs) have been extensively studied in photocatalysis because of their easy synthesis and excellent crystallinity. The effect of imine‐bond orientation on the photocatalytic properties of COFs, however, is still rarely studied. Herein, we report two novel COFs with different orientations of imine bonds using oligo(phenylenevinylene) moieties. The COFs showed similar structures but great differences in their photoelectric properties. COF‐932 demonstrated a superior hydrogen evolution performance compared to COF‐923 when triethanolamine was used as the sacrificial agent. Interestingly, the use of ascorbic acid led to the protonation of the COFs, further altering the direction of electron transfer. The photocatalytic performances were increased to 23.4 and 0.73 mmol g−1 h−1 for protonated COF‐923 and COF‐932, respectively. This study provides a clear strategy for the design of imine‐linked COF‐based photocatalysts and advances the development of COFs. [ABSTRACT FROM AUTHOR]

A simple LC-MS/MS method facilitated by salting-out assisted liquid-liquid extraction (SALLE) was applied to simultaneously investigate the pharmacokinetics of trans-resveratrol (Res) and its major glucuronide and sulfate conjugates in rat plasma. Acetonitrile-methanol (80:20, v/v) and ammonium acetate (10 mol L−1) were used as extractant and salting-out reagent to locate the target analytes in the supernatant after the aqueous and organic phase stratification, then the analytes were determined via gradient elution by LC-MS/MS in negative mode in a single run. The analytical method was validated with good selectivity, acceptable accuracy (>85%) and low variation of precision (<15%). SALLE showed better extraction efficiency of target glucuronide and sulfate conjugates (>80%). The method was successfully applied to determine Res and its four conjugated metabolites in rat after Res administration (intragastric, 50 mg kg−1; intravenous, 10 mg kg−1). The systemic exposures to Res conjugates were much higher than those to Res (AUC0- t, i.v., 7.43 μ m h; p.o., 8.31 μ m h); Res-3- O-β- d-glucuronide was the major metabolite (AUC0- t, i.v., 66.1 μ m h; p.o., 333.4 μ m h). The bioavailability of Res was estimated to be ~22.4%. The reproducible SALLE method simplified the sample preparation, drastically improved the accuracy of the concomitant assay and gave full consideration of extraction recovery to each target analyte in bio-samples. [ABSTRACT FROM AUTHOR]