Journal of agricultural and food chemistry [J Agric Food Chem] 2022 May 25; Vol. 70 (20), pp. 6050-6058. Date of Electronic Publication: 2022 May 11.
A new class of axially chiral thiazine molecules were constructed and showed promising antibacterial activities against the plant pathogen Xanthomonas oryzae pv. oryzae ( Xoo ). The axial chiralities of these compounds ( R - or S -atropisomer) showed clear impacts on the in vitro inhibitory activities against Xoo . An optimal molecule of this class with the ( S )-axially chiral configuration was identified to exhibit inhibitory activity against Xoo with an EC 50 value of 4.18 μg/mL. This inhibition efficiency is superior to that of two commercial antibacterial agrochemicals, thiodiazole-copper and bismerthiazol, as the positive controls. This hit compound also performed better than the controls in our in vivo studies. Preliminary mechanistic studies via scanning electron microscopy images showed that our hit compound at a concentration of 10 μg/mL destroyed the bacterial integrity of Xoo . Label-free quantitative proteomics analysis indicated that a total of 366 differentially expressed proteins of the rice plants were significantly influenced in the presence of our hit molecule.
Journal of agricultural and food chemistry [J Agric Food Chem] 2022 Apr 11. Date of Electronic Publication: 2022 Apr 11.
Trifluoromethylpyridine (TFMP) is a biologically active fragment formed by connecting trifluoromethyl and pyridine ring. As a result of its unique physical and chemical properties and outstanding biological activity, a variety of pesticide compounds with the TFMP fragment have been discovered and marketed and have played important roles in crop protection research. It is therefore a timely and valuable task to summarize the rationality on how to create new molecules containing TFMP fragments based on the structure-activity relationships, design mentality, and potential mechanism. This review gives a brief summary on the pesticides containing TFMP fragments in the past 5 years and introduces the latest progress of our group in this field. The aim is to provide readers with a convenient route to touch this topic and hopefully serve some educational purpose for graduate students as well.
Deng R, Wu S, Mou C, Liu J, Zheng P, Zhang X, and Chi YR
Journal of the American Chemical Society [J Am Chem Soc] 2022 Mar 30; Vol. 144 (12), pp. 5441-5449. Date of Electronic Publication: 2022 Mar 11.
Catalysis, Methane analogs derivatives, Stereoisomerism, Aldehydes, and Sulfones
A carbene-catalyzed sulfonylation reaction between enone aryl aldehydes and sulfonyl chlorides is disclosed. The reaction effectively installs sulfone moieties in a highly enantioselective manner to afford sulfone-containing bicyclic lactones. The sulfonyl chloride behaves both as an oxidant and a nucleophilic substrate (via its reduced form) in this N -heterocyclic carbene (NHC)-catalyzed process. The NHC catalyst provides both activation and stereoselectivity control on a very remote site of enone aryl aldehyde substrates. Water plays an important role in modulating catalyst deactivation and reactivation routes that involve reactions between NHC and sulfonyl chloride. Experimental studies and DFT calculations suggest that an unprecedented intermediate and a new oxidation mode of the NHC-derived Breslow intermediate are involved in the new asymmetric sulfonylation reaction.
Chemical communications (Cambridge, England) [Chem Commun (Camb)] 2021 Nov 02; Vol. 57 (87), pp. 11501-11504. Date of Electronic Publication: 2021 Nov 02.
Nickel complexes ligated by strongly donating diphosphines catalyze enantioselective hydrogenation for the preparation of acyclic and cyclic β-amido esters. A combination of acetic acid and indium powder provides protons and electrons to form nickel hydrido complexes under umpolung hydrogenation conditions.
Organic letters [Org Lett] 2021 Oct 01; Vol. 23 (19), pp. 7513-7517. Date of Electronic Publication: 2021 Sep 17.
A carbene-catalyzed reaction to synthesize chiral dihydroisoquinolinones via an o -quinodimethane ( o -QDM) intermediate is disclosed. o -QDM reacts with cyclic sulfonic imines via annulation to afford highly enantioenriched dihydroisoquinolinone products. ESI-HRMS studies suggest a stepwise Mannich addition and acylation reaction pathway, and the pathways of the catalytic and uncatalyzed background reactions are evaluated via DFT calculations.
Organic letters [Org Lett] 2021 Sep 17; Vol. 23 (18), pp. 7064-7068. Date of Electronic Publication: 2021 Sep 01.
Palladium catalyzes a domino Heck arylation and alkylation of nonconjugated cyclodienes to produce trans isomers of disubstituted cyclohexenes in exceptionally high enantiomeric ratios, reaching 100:1 to 200:1 in many cases. Importantly, the interactions of the two CF bonds of Josiphos and the sodium ion of malonates facilitates stereoselective allylic attack through DFT calculations and experiments. This is a new type of attractive noncovalent interactions found in organometallic catalysis.
Jin J, Huang X, Xu J, Li T, Peng X, Zhu X, Zhang J, Jin Z, and Chi YR
Organic letters [Org Lett] 2021 May 21; Vol. 23 (10), pp. 3991-3996. Date of Electronic Publication: 2021 May 12.
An NHC-catalyzed atroposelective reaction between ynals and urazoles is disclosed. The reaction establishes a chiral C-N axis via an atroposelective [3 + 2] annulation/desymmetrization process. Our reaction allows efficient access to axially chiral and heteroatom-rich urazole derivatives with potential applications in bioactive molecules and catalysis.
Chemical communications (Cambridge, England) [Chem Commun (Camb)] 2021 Apr 25; Vol. 57 (32), pp. 3933-3936. Date of Electronic Publication: 2021 Mar 24.
Nickel-catalyzed Heck reaction of cycloalkenes delivers unusual conjugated arylated isomers. Nickel(0) catalysts ligated by chelating dialkylphosphines effectively activate not only aryl triflates as electrophiles, but also less reactive aryl mesylates, tosylates and pivalates. The omission of bases allows nickel hydride species to exist long enough to perform in situ olefin isomerization of initial Heck adducts.