1. Towards the biodegradation pathway of fosfomycin
K Pallitsch, A Schweifer, A Roller, F Hammerschmidt Org Biomol Chem. 2017 Apr 11;15(15):3276-3285. doi: 10.1039/c7ob00546f.
Three functionalised propylphosphonic acids were synthesised to study C-P bond cleavage in R. huakuii PMY1. (R)-1-Hydroxy-2-oxopropylphosphonic acid [(R)-5] was prepared by chiral resolution of (±)-dimethyl 1-hydroxy-2-methylallyllphosphonate [(±)-12], followed by ozonolysis and deprotection. The N-(l-alanyl)-substituted (1R,2R)-2-amino-1-hydroxypropylphosphonic acid 10, a potential precursor for 2-oxopropylphosphonic acid (5) in cells, was obtained by coupling the aminophosphonic acid with benzotriazole-activated Z-l-alanine and hydrogenolytic deprotection. (1R*,2R*)-1,2-Dihydroxy-3,3,3-trifluoropropylphosphonic acid, a potential inhibitor of C-P bond cleavage after conversion into its 2-oxo derivative in the cell, was accessed from trifluoroacetaldehyde hydrate via hydroxypropanenitrile 21, which was silylated and reduced to the aldehyde (±)-23. Diastereoselective addition of diethyl trimethylsilyl phosphite furnished diastereomeric α-siloxyphosphonates. The less polar one was converted to the desired racemic phosphonic acid (±)-(1R*,2R*)-9 as its ammonium salt.
2. A Vegan Diet Is Associated with a Significant Reduction in Dietary Acid Load: Post Hoc Analysis of a Randomized Controlled Trial in Healthy Individuals
Alexander Müller, Amy Marisa Zimmermann-Klemd, Ann-Kathrin Lederer, Luciana Hannibal, Stefanie Kowarschik, Roman Huber, Maximilian Andreas Storz Int J Environ Res Public Health. 2021 Sep 23;18(19):9998. doi: 10.3390/ijerph18199998.
The composition of diet strongly affects acid-base homeostasis. Western diets abundant in acidogenic foods (meat and cheese) and deficient in alkalizing foods (fruits and vegetables) increase dietary acid load (DAL). A high DAL has been associated with numerous health repercussions, including cardiovascular disease and type-2-diabetes. Plant-based diets have been associated with a lower DAL; however, the number of trials exploring this association is limited. This randomized-controlled trial sought to examine whether an isocaloric vegan diet lowers DAL as compared to a meat-rich diet. Forty-five omnivorous individuals were randomly assigned to a vegan diet (n = 23) or a meat-rich diet (n = 22) for 4 weeks. DAL was determined using potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores at baseline and after 3 and 4 weeks, respectively. After 3 weeks, median PRAL (-23.57 (23.87)) and mean NEAPR (12.85 ± 19.71) scores were significantly lower in the vegan group than in the meat-rich group (PRAL: 18.78 (21.04) and NEAPR: 60.93 ± 15.51, respectively). Effects were mediated by a lower phosphorus and protein intake in the vegan group. Our study suggests that a vegan diet is a potential means to reduce DAL, whereas a meat-rich diet substantially increases the DAL burden.
3. Bis-Boric Acid-Mediated Regioselective Reductive Aminolysis of 3,4-Epoxy Alcohols
Wei Tang, Chuan Wang J Org Chem. 2022 Nov 18;87(22):15653-15660. doi: 10.1021/acs.joc.2c01878. Epub 2022 Nov 3.
Herein we report a bis-boric acid-mediated regioselective reductive aminolysis of 3,4-epoxy alcohols, providing new access to prepare amino diols in high diastereofidelity directly starting from nitroarenes. Notably, this step-economical process is enabled by the essential dual function of bis-boric acid, which is engaged initially in the 4,4'-bipyridine-catalyzed reduction of nitro compounds as the reductant and subsequently promotes the ring opening reaction of 3,4-epoxy alcohols with the in situ-generated anilines.
