Hydroxytyrosol, a naturally occurring chemical with antioxidant and antiviral properties, is widely used in the nutrition, pharmaceutical, and cosmetic industries. In the present study, a modularized cascade composed of Modules 1 and 2 was designed and implemented to convert l-tyrosine to hydroxytyrosol. Module 1 was a four-enzymatic cascade for converting l-tyrosine to tyrosol.
View Article and Find Full Text PDFJ Agric Food Chem
July 2024
Hydroxytyrosol, a naturally occurring compound with antioxidant and antiviral activity, is widely applied in the cosmetic, food, and nutraceutical industries. The development of a biocatalytic approach for producing hydroxytyrosol from simple and readily accessible substrates remains a challenge. Here, we designed and implemented an effective biocatalytic cascade to obtain hydroxytyrosol from 3,4-dihydroxybenzaldehyde and l-threonine via a four-step enzymatic cascade composed of seven enzymes.
View Article and Find Full Text PDFA palladium-catalyzed regioselective and asymmetric allylic alkylation of azlactones with MBH carbonates has been developed with chiral oxalamide-phosphine ligands. The corresponding reaction afforded a range of optically active γ-arylidenyl glutamic acid derivatives bearing an α-chiral quaternary stereocenter in good yields with excellent linear regio- and high enantioselectivity. This protocol furnishes an alternative approach for the construction of enantio-enriched unnatural α-amino acid derivatives.
View Article and Find Full Text PDFA one-pot, five-step domino reaction was developed for the arylation of bis-oxamides derived from optically pure 1,2-diphenylethylenediamine, leading to the formation of a series of chiral bis-oxalamide palladium(II) complexes bearing tetraaryl-conjugated substituents in good yields. In addition, these palladium(II) complexes exhibited perceptible blue fluorescence under ultraviolet light irradiation.
View Article and Find Full Text PDFAn asymmetric linear selective allylic alkylation of vinylaziridines with 3-aryl oxindoles has been developed by using a chiral oxamide-phosphine (COAP-Bn-OMe-)/palladium complex in methanol, which furnished a wide variety of 3,3-disubstituted oxindole derivatives in good yields with excellent regio- and enantioselectivities.
View Article and Find Full Text PDFThis paper presents a fuzzy PID control scheme with a real-valued genetic algorithm (RGA) to a setpoint control problem. The objective of this paper is to control a twin rotor MIMO system (TRMS) to move quickly and accurately to the desired attitudes, both the pitch angle and the azimuth angle in a cross-coupled condition. A fuzzy compensator is applied to the PID controller.
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