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The first enantioselective reduction of 2‐substituted cyclic imines to the corresponding amines (pyrrolidines, piperidines, and azepines) by imine reductases (IREDs) in non‐conventional solvents is reported. The best results were obtained in a glycerol/phosphate buffer 1 : 1 mixture, in which heterocyclic amines were produced with full conversions (>99 %), moderate to good yields (22–84 %) and excellent S‐enantioselectivities (up to >99 % ee). Remarkably, the process can be performed at a 100 mM substrate loading, which, for the model compound, means a concentration of 14.5 g L−1. A fed‐batch protocol was also developed for a convenient scale‐up transformation, and one millimole of substrate 1 a was readily converted into 120 mg of enantiopure amine (S)‐2 a with a remarkable 80 % overall yield. This aspect strongly contributes to making the process potentially attractive for large‐scale applications in terms of economic and environmental sustainability for a good number of substrates used to produce enantiopure cyclic amines of high pharmaceutical interest. [ABSTRACT FROM AUTHOR]

The rise of drug resistance to antivirals poses a significant global concern for public health; therefore, there is a pressing need to identify novel compounds that can effectively counteract strains resistant to current antiviral treatments. In light of this, researchers have been exploring new approaches, including the investigation of natural compounds as alternative sources for developing potent antiviral therapies. Thus, this work aimed to evaluate the antiviral properties of the organic-soluble fraction of a root exudate derived from the tomato plant Solanum lycopersicum in the context of herpesvirus infections. Our findings demonstrated that a root exudate from Solanum lycopersicum exhibits remarkable efficacy against prominent members of the family Herpesviridae, specifically herpes simplex virus type 1 (HSV-1) (EC50 25.57 µg/mL, SI > 15.64) and human cytomegalovirus (HCMV) (EC50 9.17 µg/mL, SI 32.28) by inhibiting a molecular event during the herpesvirus replication phase. Moreover, the phytochemical fingerprint of the Solanum lycopersicum root exudate was characterized through mass spectrometry. Overall, these data have unveiled a novel natural product with antiherpetic activity, presenting a promising and valuable alternative to existing drugs. [ABSTRACT FROM AUTHOR]

The application of biocatalysis has become essential in both academic and industrial domains for the asymmetric synthesis of chiral amines, and it serves as an alternative tool to transition‐metal catalysis and complements traditional chemical methods. It relies on the swift expansion of available processes, primarily as a result of advanced tools for enzyme discovery, combined with high‐throughput laboratory evolution techniques for optimizing biocatalysts. This concept paper explores the utilization of non‐conventional media such as ether‐type solvents, deep eutectic solvents, and micellar catalysis to enhance biocatalytic reactions for chiral amine synthesis. Each section focuses on the unique properties of these media, including their ability to stabilize enzymes, alter substrate solubility, and modulate enzyme selectivity. The paper aims to provide insights into how these innovative media can overcome traditional limitations, offering new avenues for sustainable and efficient chiral amine production through biocatalytic processes. [ABSTRACT FROM AUTHOR]

Wittig reaction between substituted phosphonium salts and (hetero)aromatic and alkyl carbonyl compounds in Deep Eutectic Solvents has been developed under a scalable and friendly protocol. Highly efficient reactions were successfully run with a wide range of bases including organic (DBU, LiTMP, t‐BuOK) and inorganic (NaOH, K2CO3) ones in ChCl/Gly 1 : 2 (mol/mol) as solvent under mild conditions, at room temperature and under air. The proposed protocol was applied to a wide range of substrates, including (hetero)aromatic aldehydes with substituents as halogens (I, Br, Cl), EDG (alkoxy, methyl), EWG (NO2, CF3) or reactive groups as CN, esters, and ketones. Vinylic, alkynyl and cycloalkyl, alicyclic and α,β‐unsaturated aldehydes can also be used. Highly electrophilic ketones gave good yields. The diastereoselectivity of the reaction is in complete agreement with the E/Z ratio predictable under traditional conditions. We demonstrated that the protocol is scalable to 2 g (5 mmol) of phosphonium salt, furthermore the proposed workup protocol allows to remove TPPO without need of additional chromatographic purification. [ABSTRACT FROM AUTHOR]

In angiosperms, the strigolactone (SL) receptor is the α/β hydrolase DWARF14 (D14) that, upon SL binding, undergoes conformational changes, triggers SL-dependent responses and hydrolyses SLs. SL signalling involves the formation of a complex between SL-bound D14, the E3-ubiquitin ligase SCFMAX2 and the transcriptional corepressors SMXL6/7/8, which become ubiquitinated and degraded by the proteasome. SL also destabilises the D14 receptor. The current model proposes that D14 degradation occurs after SMXLs ubiquitination via SCFMAX2 and proteasomal degradation. Using fluorescence and luminescence assays on transgenic lines expressing D14 fused to GREEN FLUORESCENT PROTEIN or LUCIFERASE, we showed that SL-induced D14 degradation may also occur independently of SCFMAX2 and/or SMXL6/7/8 through a proteasome-independent mechanism. Furthermore, SLs hydrolysis was not essential for triggering either D14 or SMXL7 degradation. The activity of mutant D14 proteins predicted to be non-functional for SL signalling was also examined, and their capability to bind SLs in vitro was studied using Differential Scanning Fluorimetry. Finally, we found that under certain conditions, the efficiency of D14 degradation was not aligned with that of SMXL7 degradation. These findings suggest a more complex regulatory mechanism governing D14 degradation than previously anticipated and provide novel insights into the dynamics of SL signalling in Arabidopsis., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

A methodology for the total and modulable synthesis of (4 Z )-lachnophyllum lactone ( 1 ), on a gram scale, is reported for the first time. The present work started with the design of a retrosynthetic pathway for the target compound, with the key step identified in Pd-Cu bimetallic cascade cross-coupling cyclization. (4 Z )-Lachnophyllum lactone ( 1 ) is an acetylenic furanone previously isolated, in a low amount, from the organic extract of the autotrophic weed Conyza bonariensis . Tested against the stem parasitic weed Cuscuta campestris in a seedling growth bioassay, (4 Z )-lachnophyllum lactone ( 1 ) showed almost 85% of inhibitory activity up to 0.3 mM in comparison with the control. At the same concentration, the compound displayed radicle growth inhibitory activity of the root parasitic weeds Orobanche minor and Phelipanche ramosa higher than 70 and 40%, respectively. Surprisingly, the compound showed a high percentage of inhibition, up to 0.1 mM, on C. bonariensis seed germination too. This versatile synthetic strategy was also used to obtain two further natural analogues, namely, (4 E )-lachnophyllum lactone ( 8 ) and (4 Z ,8 Z )-matricaria lactone ( 9 ), that showed, in most cases, the same inhibitory trend with slight differences, highlighting the importance of the stereochemistry and unsaturation of the side chain. Furthermore, all of the compounds showed antifungal activity at 1 mM reducing the mycelial growth of the olive pathogen Verticillium dahliae . The design and implementation of scalable and modulable total synthesis on a gram scale of acetylenic furanones allow the production of a large amount of these natural products, overcoming the limit imposed by isolation from natural sources. The results of the present study pave the way for the development of ecofriendly bioinspired pesticides with potential application in agrochemical practices as alternative to synthetic pesticides.

The current SARS-CoV-2 pandemic and the likelihood that new coronavirus strains will emerge in the immediate future point out the urgent need to identify new pan-coronavirus inhibitors. Strigolactones (SLs) are a class of plant hormones with multifaceted activities whose roles in plant-related fields have been extensively explored. Recently, we proved that SLs also exert antiviral activity toward herpesviruses, such as human cytomegalovirus (HCMV). Here we show that the synthetic SLs TH-EGO and EDOT-EGO impair β-coronavirus replication including SARS-CoV-2 and the common cold human coronavirus HCoV-OC43. Interestingly, in silico simulations suggest the binding of SLs in the SARS-CoV-2 main protease (M pro ) active site, and this was further confirmed by an in vitro activity assay. Overall, our results highlight the potential efficacy of SLs as broad-spectrum antivirals against β-coronaviruses, which may provide the rationale for repurposing this class of hormones for the treatment of COVID-19 patients.

The synthesis of acetals in acidic natural deep eutectic solvents (NADES), in which the solvent itself participates in the catalytic promotion of the reaction, is reported herein. The reaction is performed under feasible conditions, open air, without the need of external additives, catalysts or water-removing techniques, and it is wide in scope. The products are easily recovered, and the reaction medium is fully recycled and reused without weakening of its catalytic activity after 10 times. Remarkably, the entire process has been realized on gram scale., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

A straightforward and efficient protocol to promote the metalation/anionic Fries rearrangements of O-aryl carbamates, using for the first time a lithium amide as metalating agent under aerobic/ambient-friendly reaction conditions, is reported. This approach enables the sustainable preparation of salicylamide derivatives with high levels of chemoselectivity within ultrafast reaction times, working at room temperature in the presence of air/moisture, and using environmentally responsible cyclopentyl methyl ether as a solvent. Furthermore, the regioselective manipulation of O-2-tolyl carbamates has been accomplished using interchangeably alkyllithiums or lithium amides, with an unexpected beneficial contribution from the employment of biorenewable protic eutectic mixtures as non-innocent reaction media., (© 2022 Wiley-VCH GmbH.)