Article
Chemistry, Organic
Si-Yu Wang, Zhong-Wei Zhang, Liu Yuan, Yi Jin, Cong-Hai Zhang, Jun Lin
Summary: An efficient and simple method for the preparation of 2-pyridinone is reported, using 3-hydroxy-2-aryl acrylate and nitro ketene aminal as substrates. The obtained products included various bicyclic 2-pyridinones and multi-substituted 6-amino-2-pyridinones, with good to excellent yields. This method can be used for the synthesis of bicyclic 2-pyridinones, as well as multi-substituted complex 2-pyridinones.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Enrique Reyes-Bravo, Dino Gnecco, Jorge R. Juarez, Maria L. Orea, Sylvain Bernes, David M. Aparicio, Joel L. Teran
Summary: This study describes the synthesis of new chiral highly functionalized zwitterionic bicyclic lactams starting from acyclic beta-enaminoesters derived from (R)-(-)-2-phenylglycinol. The key step involves an intramolecular non-classical Corey-Chaykovsky ring-closing reaction of the corresponding sulfonium salts derived from beta-enaminoesters. This methodology allows for the generation of two or three new stereogenic centers with high diastereoselectivity, and the utility of these intermediates was demonstrated by the stereocontrolled total synthesis of cis-4-hydroxy-2-methyl piperidine and its corresponding pipecolic acid derivative.
Article
Chemistry, Organic
Jun Yan, Christine Tran, Pascal Retailleau, Mouad Alami, Abdallah Hamze
Summary: Functionalized 4-aryl-4H-benzo[d][1,3]oxazines were synthesized using ortho-amide-N-tosylhydrazones under transition-metal-free conditions. This method utilizes readily available N-tosylhydrazones as the diazo compound precursors and involves an intramolecular ring closure reaction mediated by a protic polar additive (iPrOH), resulting in a wide range of functionalized oxazines in good to excellent yields. Additionally, the feasibility of this strategy was demonstrated by the gram-scale elaboration of a bromo-substituted 4H-benzo[d][1,3]oxazine and its post-functionalization through palladium-catalyzed cross-couplings.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Mahmood Sanchooli, Hojjat Delarami Samareh, Mahdiye Poorsargol, Pouya Karimi, Fatemeh Rashki Ghaleno
Summary: A proper descriptor was proposed to correlate pIC50 of a series of 19 substituted 6-amino, 4-phenyl, tetrahydroquinoline (6A4PTHQ) derivatives with their non-conventional intramolecular hydrogen bond (nCIHB). Solvents, especially protic solvents, were found to weaken nCIHB in all 6A4PTHQ derivatives. The study provides a way to clarify the complex role of nCIHB in drug transport and absorption processes.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Organic
Thomas Mies, Andrew J. P. White, Philip J. Parsons, Anthony G. M. Barrett
Summary: The synthesis of 8-hydroxyisochroman-1-one derivatives was described using a base-induced anionic accelerated rearrangement reaction, providing important compounds for further study.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Inorganic & Nuclear
Almira R. Miftyakhova, Maria D. Matveeva, Dmitry Zhilyaev, Oleg S. Eltsov, Giovanni Talarico, Alexander F. Smol'yakov, Leonid G. Voskressensky, Ilya Efimov
Summary: A mild, simple, and efficient method for the synthesis of ortho, meta, and para-fluoroaryl substituted pyrroles was discovered. Through NMR spectroscopy, it was found that ortho-fluoroaryl substituted pyrroles exist as inhibited conformational isomers, with intramolecular interactions between the hydrogen and fluorine atoms. The ratio of obtained rotamers was determined to be constant regardless of temperature, based on 2D HMBC and HSQC NMR spectroscopy.
JOURNAL OF FLUORINE CHEMISTRY
(2021)
Article
Chemistry, Organic
Haiwen Li, Junhu Xin, Yuhang Xue, Cunde Wang
Summary: A pseudo-three-component annulation reaction was investigated to access polysubstituted 5H-chromeno[2,3-b]pyridines. This reaction involved a sequential intermolecular addition/cyclization/epoxidation/ring opening/aromatization sequence, providing an efficient and atom economical approach for the synthesis of 3-hydroxy-5H-chromeno[2,3-b]pyridines from readily available substrates.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Anna Irto, Paola Cardiano, Karam Chand, Rosalia Maria Cigala, Francesco Crea, Concetta De Stefano, Maria Amelia Santos
Summary: By investigating the binding ability of bifunctional 3-hydroxy-4-pyridinones with Cu2+ and Fe3+, different speciation schemes were determined, showcasing the potential selectivity of these ligands towards Fe3+ as promising iron-chelating agents. The study also suggested that 3-hydroxy-4-pyridinones could avoid competition with essential metal cations like Cu2+ and Zn2+, making them advantageous in biological and environmental applications.
Article
Chemistry, Organic
Yan Zheng, Siqi Dong, Kai Xu, Delong Liu, Wanbin Zhang
Summary: An efficient Pd-catalyzed asymmetric allylic substitution cascade reaction has been developed for the synthesis of chiral compounds. The reaction achieved high yields and high enantioselectivity under temperature-controlled conditions, and can be performed on a gram scale. The resulting product is versatile and can undergo various transformations.
Article
Chemistry, Organic
Lukas Janecky, Athanasios Markos, Blanka Klepetar, Petr Beier
Summary: 4-Aryl-5-allyl-N-fluoroalkyl-1,2,3-triazoles were synthesized through a three-component reaction of fluoroalkyl azides, copper acetylides, and allyl halides. These compounds underwent aluminum halide-mediated transformation to N-(4-halo-2-aryl-cyclopentenyl) imidoyl halides by cyclization of vinyl cation intermediates, followed by halide capture. The cyclic products could be further utilized for the synthesis of N-alkenyl amides, amidines, isoquinolines, and tetrazoles, or for the subsequent modification of the cyclopentene ring.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Arkajyoti Sengupta, K. N. Houk
Summary: This study investigates the reaction mechanism for intramolecular cycloadditions of a heptafulvenyl-fulvene tethered by a trimethylene chain using quantum mechanical calculations and molecular dynamics simulations. The experimental reports of temperature dependence on the periselectivity of intramolecular cycloadditions are explained by the mechanistic details. Furthermore, additional calculations with multireference-based methods highlight the limitations of DFT methods and single-reference wavefunction-based CCSD(T) in describing the complete potential energy surface involving various cycloadditions of the heptafulvenyl-fulvene.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Organic
Sergey A. Usachev, Vladislav V. Fedin, Dmitrii L. Obydennov, Vyacheslav Y. Sosnovskikh
Summary: The tandem acylation-heterocyclization of ketene dithioacetals was performed using soft enolization in the MgBr2·OEt2/NEt3 system. A series of 3,6-substituted 2-methylthio-4-pyrones were obtained with a wide functional group tolerance. The obtained 2-methylthio-4-pyrones were demonstrated to undergo transformations, including substitution of the SMe group with N-nucleophiles, for the preparation of functionalized 4-pyrones as analogs of bioactive molecules.
TETRAHEDRON LETTERS
(2023)
Article
Chemistry, Applied
Jiaqing Xu, Wangyu Shi, Min Liu, Jianning Liao, Wei Wang, Yongjun Wu, Hongchao Guo
Summary: A palladium-catalyzed [4+2] cycloaddition reaction has been developed for the efficient synthesis of tetrahydropyran derivatives with good selectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Plant Sciences
Wen Li, Jie Fan, Ge Liao, Wen-Bing Yin, Shu-Ming Li
Summary: Expression of a nonribosomal peptide synthetase-nonreducing polyketide synthase hybrid gene pcr10109 from Penicillium crustosum PRB-2 in Aspergillus nidulans led to the accumulation of 4-hydroxy-6-(4-hydroxyphenyl)-alpha-pyrone (1). Adding para-hydroxybenzoic acid into the medium in which the overexpressing mutant is growing increased the product yield up to 5-fold. This strategy could be helpful for heterologous gene expression experiments requiring special substrates for product formation.
JOURNAL OF NATURAL PRODUCTS
(2021)
Article
Chemistry, Multidisciplinary
Yaqin Wang, Bingfeng Chen, Haihong Wu, Xuelei Mei, Kaili Zhang, Bingxiao Zheng, Wanying Han, Jiao Xu, Mingyuan He, Buxing Han
Summary: Catalytic transfer hydrogenation is a feasible and safe method for the hydrodeoxygenation of biomass, enabling its effective utilization. A sustainable route for the production of delta-lactam has been demonstrated through catalytic transfer hydrogenation/hydrogenolysis of 4-hydroxy-6-methylpyridin-2(1H)-one derived from biomass-derived triacetic acid lactone. Ni-Ru bimetallic catalysts supported on carbon showed excellent catalytic performance, with a desired product yield of 83.5%, higher than other bimetallic or monometallic catalysts and commercial catalysts.
