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Objective: This is a cross-sectional study that compares the sales of "healthy" and "unhealthy" vending machines following the introduction of healthier vending machines on a university campus. Method: Healthy ("green" and "amber" category), competitively priced snacks and beverages in vending machines (n = 4) called "Grab Goodness" were placed alongside standard vending machines (n = 11). The monthly sales data from all vending machines were captured electronically for 20 months. Results: Assortment of snacks and beverages offered by standard vending machines were of low nutritional quality, with only 16% of all products categorized as "green." The new Grab Goodness machines accounted for 28% of all vending machine purchases over 20 months, and 50% of all products purchased through these machines were "green" category items. Conclusions: The purchases of healthier snack options demonstrate encouraging patterns that support more nutritious and healthy alternatives in vending machines.

The diterpene synthase AfAS was identified from Aspergillus fumigatiaffinis. Its amino acid sequence and—according to a structural model—active site architecture are highly similar to those of the fusicocca‐2,10(14)‐diene synthase PaFS, but AfAS produces a structurally much more complex diterpene with a novel 6–5–5–5 tetracyclic skeleton called asperfumene. The cyclisation mechanism of AfAS was elucidated through isotopic labelling experiments and DFT calculations. The reaction cascade proceeds in its initial steps through similar intermediates as for the PaFS cascade, but then diverges through an unusual vicinal deprotonation‐reprotonation process that triggers a skeletal rearrangement at the entrance to the steps leading to the unique asperfumene skeleton. The structural model revealed only one major difference between the active sites: The PaFS residue F65 is substituted by I65 in AfAS. Intriguingly, site‐directed mutagenesis experiments with both diterpene synthases revealed that position 65 serves as a bidirectional functional switch for the biosynthesis of tetracyclic asperfumene versus structurally less complex diterpenes. [ABSTRACT FROM AUTHOR]

Die Diterpensynthase AfAS wurde aus Aspergillus fumigatiaffinis identifiziert. Ihre Aminosäuresequenz und – einem Strukturmodell zufolge – die Architektur des aktiven Zentrums sind denen der Fusicocca‐2,10(14)‐dien‐Synthase PaFS sehr ähnlich, AfAS produziert jedoch ein strukturell viel komplexeres Diterpen mit einem neuartigen 6–5–5–5 tetracyclischen Gerüst namens Asperfumen. Der Cyclisierungsmechanismus von AfAS wurde durch Isotopenmarkierungsexperimente und DFT‐Rechnungen aufgeklärt. Die Reaktionskaskade verläuft in ihren ersten Schritten über ähnliche Intermediate wie die PaFS‐Kaskade, divergiert dann aber durch einen ungewöhnlichen vicinalen Deprotonierungs‐Reprotonierungsprozess, der eine Skelettumlagerung am Startpunkt der Stufen auslöst, die zum einzigartigen Asperfumen‐Gerüst führen. Das Strukturmodell zeigte nur einen wesentlichen Unterschied zwischen den aktiven Zentren: Der PaFS‐Rest F65 ist in AfAS durch I65 ersetzt. Interessanterweise zeigten ortsspezifische Mutageneseexperimente mit beiden Diterpensynthasen, dass Position 65 als bidirektionaler funktioneller Schalter für die Biosynthese von tetracyclischem Asperfumen im Vergleich zu strukturell weniger komplexen Diterpenen dient. [ABSTRACT FROM AUTHOR]

An I2-mediated [3+2+1] aerobic cyclization reaction of anilines with alkynes and tertiary amines without any peroxides has been reported. This protocol employed tertiary amines as a C1 building block for the direct synthesis of 2-non, 2-alkyl, and even 2-aryl substituted quinolines via C–N bond cleavage. Differing from the traditional methods, both terminal and internal alkynes were compatible in this metal-free three-component system. It is possible that the 2-vinylbenzenamine species might be produced as one of the active intermediates in this process. [ABSTRACT FROM AUTHOR]