2019

2019-01- Acid Fluorides in Transition‐Metal Catalysis: A Good Balance between Stability and Reactivity

Blanchard, N.; Bizet, V. Angew. Chem. Int. Ed. 2019, 58, 6814-6817.
Several recent reports outlined the singular reactivity of acid fluorides as excellent electrophiles in transition‐metal catalysis. These species undergo oxidative addition of the metal into the C−F bond; then, retention or release of the CO moiety can occur and be controlled by tuning the catalytic system and the reaction parameters. Acid fluorides, which can be derived from carboxylic acids, show good stability and high reactivity in a wide range of possible functionalizations with nucleophiles. Their use provides an interesting alternative to that of the parent carboxylic acid derivatives (acid chlorides, esters, amides, acids, or aldehydes). 
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2019-02- Ruthenium-catalyzed ring-opening reaction of a 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with amines — an unexpected mode of ring-opening

Tait, K.; Koh, S.; Blanchard, N.; Tam, W. Can. J. Chem. 2019, 97, 310-316.
The ruthenium-catalyzed ring-opening reaction of a 3-aza-2-oxabicyclo[2.2.1]hept-5-ene with amines was investigated. In the presence of an amine and a ruthenium catalyst, the N–O bond is cleaved, forming a ring-opened allylic alcohol product. Through a possible ruthenium-catalyzed redox isomerization, the allylic alcohol is transformed into a saturated carbonyl product. This unexpected mode of ruthenium-catalyzed ring-opening reaction of a 3-aza-2-oxabicyclo[2.2.1]hept-5-ene leads to the formation of a cyclopentanone derivative in moderate yields.
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2019-03- Ipomoeassin F Binds Sec61α to Inhibit Protein Translocation

Zong, G.; Hu, Z.; O’Keefe, S.; Tranter, D.; Iannotti, M. J.; Baron, L.; Hall, B.; Corfield, K.; Paatero, A. O.; Henderson, M. J.; Roboti, P.; Zhou, J.; Sun, X.; Govindarajan, M.; Rohde, J. M.; Blanchard, N.; Simmonds, R.; Inglese, J.; Du, Y.; Demangel, C.; High, S.; Paavilainen, V. O.; Shi, W. Q. J. Am. Chem. Soc. 2019, 141, 8450-8461
Ipomoeassin F is a potent natural cytotoxin that inhibits growth of many tumor cell lines with single-digit nanomolar potency. However, its biological and pharmacological properties have remained largely unexplored. Building upon our earlier achievements in total synthesis and medicinal chemistry, we used chemical proteomics to identify Sec61α (protein transport protein Sec61 subunit alpha isoform 1), the pore-forming subunit of the Sec61 protein translocon, as a direct binding partner of ipomoeassin F in living cells.
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2019-04- Design, synthesis and biological evaluation of antimicrobial diarylimine and –amine compounds targeting the interaction between the bacterial NusB and NusE proteins

Qiu, Y.; Chan, S. T.; Lin, L.; Shek, T. L.; Tsang, T. F.; Barua, N.; Zhang, Y.; Ip, M.; Chan, P. K.-s.; Blanchard, N.; Hanquet, G.; Zuo, Z.; Yang, X.; Ma, C. Eur. J. Med. Chem. 2019, 178, 214-231
Discovery of antimicrobial agents with a novel model of action is in urgent need for the clinical management of multidrug-resistant bacterial infections. Recently, we reported the identification of a first-in-class bacterial ribosomal RNA synthesis inhibitor, which interrupted the interaction between the bacterial transcription factor NusB and NusE. In this study, a series of diaryl derivatives were rationally designed and synthesized based on the previously established pharmacophore model.
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2019-05- Recombinant Antibodies against Mycolactone

Naranjo, L.; Ferrara, F.; Blanchard, N.; Demangel, C.; D’Angelo, S.; Erasmus, F. M.; Teixera, A. A.; Bradbury, R. A Toxins 2019, 11, 346.
In the past, it has proved challenging to generate antibodies against mycolactone, the primary lipidic toxin A of Mycobacterium ulcerans causing Buruli ulcer, due to its immunosuppressive properties. Here we show that in vitro display, comprising both phage and yeast display, can be used to select antibodies recognizing mycolactone from a large human naïve phage antibody library.
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2019-06- Activating Pyrimidines by Pre-distortion for the General Synthesis of 7-Aza-indazoles from 2-Hydrazonylpyrimidines via Intramolecular Diels–Alder Reactions

Le Fouler, V.; Chen, Y.; Gandon, V.; Bizet, V.; Salome, C.; Fessard, T.; Liu, F.; Houk, K. N.; Blanchard, N. J. Am. Chem. Soc. 2019, 141, 15901-15909
Pyrimidines are almost unreactive partners in Diels–Alder cycloadditions with alkenes and alkynes, and only reactions under drastic conditions have previously been reported. We describe how 2-hydrazonylpyrimidines, easily obtained in two steps from commercially available 2-halopyrimidines, can be exceptionally activated by trifluoroacetylation. This allows a Diels–Alder cycloaddition under very mild reaction conditions, leading to a large diversity of aza-indazoles, a ubiquitous scaffold in medicinal chemistry.
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