A new methodology for the synthesis of chalcogenoenynes is described. The palladium-catalyzed cross-coupling reaction of 1,2-bis(organanylchalcogeno)-alkenes and 1-alkynes gave the corresponding chalcogenoenynes in 71% to 88% yields. Preliminary pharmacologycal tests suggest that chalcogenoenynes may be useful drugs as anti-inflammatory and antinociceptive agents.
This review surveys literature from 2010 to 2025 on Aspergillus-derived enzymes for kinetic resolution (KR), using conventional databases and AI-assisted platforms. Among over 340 species, A. niger, A. oryzae, and A. terreus are widely recognized as safe and industrially relevant. Lipases from these fungi exhibit high stability, broad substrate specificity, and enantioselectivity, enabling efficient resolution of racemic mixtures. Advances in enzyme immobilization, protein engineering, and reaction medium optimization have enhanced catalytic performance under diverse conditions. Complementary enzymes, including esterases and epoxide hydrolases, further expand biocatalytic applications. Despite increasing demand for enantiopure compounds, challenges in yield, scalability, and enzyme discovery call for integrated molecular and process strategies. Aspergillus spp. emerge as a promising system for high-level enzyme expression, offering robust secretion capacity, efficient post-translational processing, and strong adaptability for industrial biocatalysis.
27 February 2023 in Biocatalysis and Biotransformation
The present work deals with the preparation and characterization of Zn2Al layered double hydroxides (LDHs) intercalated with chloride and dodecyl sulfate ions and their use as supports for the immobilization of Pseudomonas cepacia lipase (LipPS). LipPS was immobilized on LDH by adsorption, in situ entrapment and delamination entrapment methods. The performance of free and immobilized LipPS in the transesterification of (R,S)-1-phenylethanol was compared. The immobilized derivatives prepared by adsorption gave the highest conversions (c = 50%), with an enantiomeric excess of the product (eep) greater than 99% and a high enantiomeric ratio (E > 200). For immobilization by in situ entrapment (coprecipitation), a conversion of 31.5% and E > 200 were obtained. For immobilization by delamination entrapment, a conversion of 36% and E= 155 were obtained. Although the best results were obtained by adsorption, these results show that the delamination entrapment method can also be used to prepare bioinorganic-enzyme materials based on LDH. Our work therefore increases the range of methods that can be used to immobilize lipases for use in the production of optically pure secondary alcohols. Graphical abstract