2243-53-0Relevant articles and documents
Highly Regioselective 5-endo-tet Cyclization of 3,4-Epoxy Amines into 3-Hydroxypyrrolidines Catalyzed by La(OTf)3
Hoshino, Yoshihiko,Iwabuchi, Yoshiharu,Kuriyama, Yuse,Sasano, Yusuke,Uesugi, Shun-ichiro,Yamaichi, Aoto
supporting information, p. 1961 - 1965 (2021/01/04)
Highly regioselective intramolecular aminolysis of 3,4-epoxy amines has been achieved. Key features of this reaction are (1) chemoselective activation of epoxides in the presence of unprotected aliphatic amines in the same molecules by a La(OTf)3 catalyst and (2) excellent regioselectivity for anti-Baldwin 5-endo-tet cyclization. This reaction affords 3-hydroxy-2-alkylpyrrolidines stereospecifically in high yields. DFT calculations revealed that the regioselectivity might be attributed to distortion energies of epoxy amine substrates. The use of this reaction was demonstrated by the first enantioselective synthesis of an antispasmodic agent prifinium bromide.
Nickel-catalyzed electrocarboxylation of allylic halides with CO2
Wu, La-Xia,Deng, Fang-Jie,Wu, Lin,Wang, Huan,Chen, Tai-Jie,Guan, Ye-Bin,Lu, Jia-Xing
, p. 13137 - 13141 (2021/08/03)
Nickel-catalyzed regioselective electrocarboxylation of allylic halides with CO2at atmospheric pressure has been developed by adjusting reaction parameters, including catalyst, solvent, temperature and additive. β,γ-Unsaturated carboxylic acids were obtained in moderate to good yields and with high chain selectivity. This reaction shows tolerance to functional groups. In addition, cyclic voltammetry was performed to provide the possible mechanism of nickel-catalyzed CO2allylation.
Photo-Promoted Decarboxylative Alkylation of α, β-Unsaturated Carboxylic Acids with ICH2CN for the Synthesis of β, γ-Unsaturated Nitriles
Pan, Chunxiang,Yang, Chunhui,Li, Kangkui,Zhang, Keyang,Zhu, Yuanbin,Wu, Shiyuan,Zhou, Yongyun,Fan, Baomin
supporting information, p. 7188 - 7193 (2021/10/01)
An efficient, catalyst/photocatalyst-free, and cost-effective methodology for the decarboxylative alkylation of α,β-unsaturated carboxylic acids to synthesize β,γ-unsaturated nitriles has been developed. The reaction proceeded in an environmentally benign atmosphere of blue light-emitting diode irradiation with K2CO3 and water at room temperature. The methodology worked for a wide range of substrates (22 examples) with up to 83% yield. The protocol is also compatible for gram-scale synthesis.
Synthesis of (+) and (-)-Streptomyces coelicolor Butanolide 5 (SCB-5)
Brüggemann, Moritz,Donges, Jonas,Frank, Andrea,Hofmann, Sandra,Nubbemeyer, Udo,Schollmeyer, Dieter
supporting information, p. 3345 - 3358 (2021/06/26)
Various 1-(1-hydroxyalkyl) paraconyl alcohols are important signaling molecules within antibiotics production in Streptomyces sp. Intending developing a flexible convergent chemical synthesis of such butanolides, a zwitterionic aza-Claisen rearrangement was chosen as reliable strategy generating the central stereotriad. Reaction of enantiopure N-allyl pyrrolidines and 4-phenylbutenoic acid fluoride delivered defined configured amides displaying the 2,3,1’ stereotriads. The configuration was determined by the allyl alcohol moiety indicating a complete remote stereo control. Amide removal by iodolactonization and proceeding reductions, halocyclization and elimination gave key alkylidene tetrahydrofuran derivatives. Stepwise degradation of the olefins through ozonolysis, reductive work-up and protecting group removal delivered both enantiomers of the target Streptomyces coelicolor butanolide 5.
sEH Inhibitor or pharmaceutically acceptable composition thereof as well as preparation method and application thereof
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Paragraph 0125-0126, (2021/09/21)
The invention provides sEH inhibitor or a pharmaceutically acceptable composition and a preparation method and application thereof, and belongs to the technical field of medicines. sEH Inhibitor or a pharmaceutically acceptable composition thereof according to the present invention is provided, and the sEH inhibitor has the structure shown I. sEH Inhibitor provided by the invention can stabilize an endogenous substance epoxy fatty acid with wide physiological activity, has a strong inhibition effect on human recombinant sEH, and can be used for regulating the generation of a plurality of pro-inflammatory cytokines. The invention relieves the stress of endoplasmic reticulum, prevents or reverses the dysfunction of endothelial dysfunction, stabilizes mitochondria function multiple action mechanisms to obviously relieve neuropathic pain, and can effectively avoid adverse reactions related to the target spot. Furthermore, the sEH inhibitor structure provided by the invention does not contain free carboxyl groups, can avoid adverse reactions such as gastrointestinal irritation caused by oral administration, and is small in adverse reaction, high in bioavailability, excellent in analgesic effect and small in administration amount.
Palladium-Catalyzed Direct C-H Arylation of 3-Butenoic Acid Derivatives
Yang, Shan,Liu, Lingling,Zhou, Zheng,Huang, Zhibin,Zhao, Yingsheng
supporting information, p. 296 - 299 (2021/01/13)
We report herein a direct method to synthesize 4-aryl-3-butenoic acid through a carboxylic-acid-directed oxidative Heck reaction. The various 4-aryl-3-butenoic acids are easily prepared in moderate to good yields. In view of the promising bioactivity of 4-phenyl-3-butenoic acid previously reported, its derivatives reported here may be bioactive.
Inter-and Intramolecular Cycloaddition Reactions of Ethenetricarboxylates with Styrenes and Halostyrenes
Yamazaki, Shoko,Wang, Zhichao,Iwata, Kentaro,Katayama, Khotaro,Sugiura, Hirotaka,Mikata, Yuji,Morimoto, Tsumoru,Ogawa, Akiya
supporting information, p. 731 - 753 (2020/11/18)
Inter-and intramolecular cycloaddition reactions of ethenetricarboxylates with styrenes and α-halostyrenes have been investigated. The reactions of ethenetricarboxylates with styrenes or α-bromostyrenes in the presence of SnCl 4or SnBr 4stereoselectively gave 2,4-cis-substituted cyclobutanes. The intramolecular cycloaddition reactions of a series of styrene-functionalized ethenetricarboxylate amides, including in situ generated derivatives, showed high diversity of reaction modes depending on the structures and substituents of the substrates. The regioselectivity and stereoselectivity of the reactions as well as reaction mechanisms were discussed based on the DFT calculations.
Electroreductive Cobalt-Catalyzed Carboxylation: Cross-Electrophile Electrocoupling with Atmospheric CO2
Ackermann, Lutz,Ang, Nate W. J.,Oliveira, Jo?o C. A.
supporting information, p. 12842 - 12847 (2020/06/02)
The chemical use of CO2 as an inexpensive, nontoxic C1 synthon is of utmost topical interest in the context of carbon capture and utilization (CCU). We present the merger of cobalt catalysis and electrochemical synthesis for mild catalytic carb
An Enzymatic Platform for the Highly Enantioselective and Stereodivergent Construction of Cyclopropyl-δ-lactones
Chandgude, Ajay L.,Fasan, Rudi,Liu, Ningyu,Ren, Xinkun
supporting information, p. 21634 - 21639 (2020/09/23)
Abiological enzymes offers new opportunities for sustainable chemistry. Herein, we report the development of biological catalysts derived from sperm whale myoglobin that exploit a carbene transfer mechanism for the asymmetric synthesis of cyclopropane-fused-δ-lactones, which are key structural motifs found in many biologically active natural products. While hemin, wild-type myoglobin, and other hemoproteins are unable to catalyze this reaction, the myoglobin scaffold could be remodeled by protein engineering to permit the intramolecular cyclopropanation of a broad spectrum of homoallylic diazoacetate substrates in high yields and with up to 99 % enantiomeric excess. Via an alternate evolutionary trajectory, a stereodivergent biocatalyst was also obtained for affording mirror-image forms of the desired bicyclic products. In combination with whole-cell transformations, the myoglobin-based biocatalyst was used for the asymmetric construction of a cyclopropyl-δ-lactone scaffold at a gram scale, which could be further elaborated to furnish a variety of enantiopure trisubstituted cyclopropanes.
Synthesis of Allylboranes via Cu(I)-Catalyzed B-H Insertion of Vinyldiazoacetates into Phosphine-Borane Adducts
Drikermann, Denis,M??el, Robert S.,Al-Jammal, Walid K.,Vilotijevic, Ivan
supporting information, p. 1091 - 1095 (2020/02/15)
Cu(I) catalysts enable C-B bond formation via direct insertion of vinyldiazoacetates into B-H bonds of borane-phosphine Lewis adducts to form phosphine-protected allylboranes under mild conditions. The resulting allylborane-phosphine Lewis adducts can be used in the diastereoselective allylation of aldehydes directly without the need for removal of the phosphine. The allylation reaction proceeds with high diastereoselectivity and yields 5,6-disubstituted dihydropyranones after treatment with an appropriate acid.
