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6‐Alkyl‐6‐hydroxycyclohexa‐2,4‐dienone derivatives, commonly referred to as ortho‐quinols, and their simple ester and ether variants constitute a class of organic compounds that aroused much interest amongst chemists over the past 70 years for several reasons related to organic synthesis, natural product chemistry and biochemistry. It was very early on that organic chemists understood the potential of the unique yet versatile chemical reactivity of such compounds to synthesize more complex structures, and it soon emerged that ortho‐quinols could constitute key intermediates in the biosynthesis of certain natural products of various origins. This minireview discusses the chemistry of ortho‐quinols from the point of view of their role in the synthesis and biosynthesis of natural products. Examples of completed syntheses of natural products mostly taken in the literature of the last 20 years or so, together with some chosen pieces from older but pioneering and most remarkable works, are highlighted to illustrate this discussion. [ABSTRACT FROM AUTHOR]

Abstract: The electrodeposition of Pt on glassy carbon (GC) and gas diffusion layer (GDL) surfaces in dilute chloroplatinic acid solutions (10 mM PtCl4 2− in 0.5 M NaCl) was performed potentiodynamically in the absence and presence of ultrasound (20 kHz) at various ultrasonic powers (up to 6 W) respectively and at (313 ± 2) K. In our conditions, it was found that platinum electrodeposition is an irreversible process which requires a substantial overpotential to drive the formation of Pt nuclei on the GC and GDL surfaces; however, under sonication Pt electrodeposition becomes more facile due to lower concentration and nucleation overpotentials and overall currents are significantly increased compared to silent conditions. It was also observed that the specific electrochemical surface area (SECSA) was significantly affected for Pt/GC and Pt/GDL electrodes prepared in the presence of rotation (GC only) and under sonication compared to those prepared under silent conditions. This finding was explained to be due to both larger and agglomerated platinum nanoparticles formed on the GC and GDL surface caused by forced convection. It was also found that ultrasound produced larger Pt nanoparticles on GC electrodes than those on GDL electrodes. [Copyright &y& Elsevier]

Abstract Objective To assess the performance of angiography derived Fractional Flow Reserve (FFRangio) in multivessel disease (MVD) patients undergoing angiography. Background FFR is the reference standard for physiologic assessment of coronary stenosis and guidance of revascularization, especially in patients with MVD, yet it remains grossly underutilized. The non-wire based FFRangio performs well in non-MVD patients, but its accuracy in MVD is unknown. Methods A prospective clinical study was conducted at Gifu Heart Centre, Japan. Patients underwent physiologic assessment of all relevant coronary lesions using wire-based FFR (wbFFR) and FFRangio. Primary outcome was diagnostic performance (sensitivity, specificity, accuracy) for FFRangio with wbFFR as reference. Other outcomes were the correlation between wbFFR/FFRangio, time required for wbFFR/FFRangio measurements, and the effect of wbFFR/FFRangio on the reclassification of coronary disease severity. Results Fifty patients (118 lesions in total) were included. Mean age was 72 ± 9 years, 72% were male, 36% had triple vessel disease and the average SYNTAX score was 13. The mean measurement of wbFFR and FFRangio were 0.83 ± 0.12 and 0.81 ± 0.11, respectively. Accuracy, sensitivity and specificity for FFRangio were 92.3% (95% CI 79.1–98.4%), 92.4% (95% CI 84.3–97.2%) and 92.4% (95% CI 87.4–97.3%), respectively. Pearson's r between wbFFR and FFRangio was 0.83. FFRangio measurement was faster than wbFFR (9.6 ± 3.4 vs. 15.0 ± 8.9 min, p < 0.001). Conclusions In patients with MVD, FFRangio shows good correlation and excellent diagnostic performance compared to wbFFR, and measuring FFRangio is faster than wbFFR. These results highlight the potential clinical benefits of utilizing FFRangio among patients with MVD. Highlights • FFR is grossly underutilized in clinical practice. • Angiography derived FFR modalities may help increase the use of physiologic assessment, but their accuracy in MVD patients has not been examined. • In MVD patients, FFRangio showed excellent diagnostic performance, while saving roughly a third of the time required for physiologic assessment. • The effect of FFRangio on functional SYNTAX score calculation/reclassification of coronary disease severity was similar to that of invasive FFR [ABSTRACT FROM AUTHOR]