Results 1 to 10 of about 131,428 (405)
Two-step synthesis of chiral fused tricyclic scaffolds from phenols via desymmetrization on nickel
Nature Communications, 2017 Tricyclic furanic compounds with multiple chiral centers are found in a variety of natural products. Here, the authors show a highly enantioselective nickel-catalyzed procedure to access tricyclic oxygen-containing scaffolds with five contiguous chiral ...
Ravindra Kumar +4 more
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Synthesis and Thermal Behavior of a Fused, Tricyclic 1,2,3,4‐Tetrazine Ring System
Angewandte Chemie - International Edition, 2015 This study presents the synthesis and characterization of a fused, tricyclic 1,2,3,4-tetrazine ring system. The molecule is synthesized in a three-step process from 5,5'-dinitro-bis,1,2,4-triazole via a di-N-amino compound.
D. Chavez +3 more
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Highly efficient construction of angular polycycles [PDF]
Nature CommunicationsAngular tricyclic and polycyclic skeletons feature typical cores in an intriguing type of natural products. We herein report the Lewis acids-catalyzed dearomative (3 + 2) cycloadditions of donor-acceptor cyclopropanes with benzene ring, by which ...
Yi Sun +3 more
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Geochemical application of tricyclic and tetracyclic terpanes biomarkers in crude oils of NW China
Marine and Petroleum Geology, 2015 Manfredi Rizzo
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EXTREMAL IOTA ENERGY OF A SUBCLASS OF TRICYCLIC DIGRAPHS AND SIDIGRAPHS [PDF]
Matrix Science Mathematic, 2018 The iota energy of an n-vertex digraph D is defined by Ec (𝐷) = ∑ 1 |Im(𝑧 k)|, where z1, . . ., zn are eigenvalues of D and Im(zk) is the imaginary part of eigenvalue zk . The iota energy of an n-vertex sidigraph can be defined analogously.
Fareeha Jamal, Mehtab Khan
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Fixed Points Results for Various Types of Tricyclic Contractions
Axioms, 2021 In this paper, we introduce four new types of contractions called in this order Kanan-S-type tricyclic contraction, Chattergea-S-type tricyclic contraction, Riech-S-type tricyclic contraction, Cirić-S-type tricyclic contraction, and we prove the ...
Mustapha Sabiri +3 more
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Iraqi Geological Journal, 2021 Eight cuttings samples were obtained from Sargelu and Kurrachine formations in different wells at different depths to detect steranes and triterpanes biomarkers as an indicator of the depositional environments and thermal maturity of organic matter. This
Al-Dolaimy, Arwa
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Click-Free Synthesis of a Multivalent Tricyclic Peptide as a Molecular Transporter
Pharmaceutics, 2020 The cellular delivery of cell-impermeable and water-insoluble molecules remains an ongoing challenge to overcome. Previously, we reported amphipathic cyclic peptides c[WR]4 and c[WR]5 consisting of alternate arginine and tryptophan residues as nuclear ...
Sumit Kumar +5 more
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Fused Tricyclic Guanidine Alkaloids: Insights into Their Structure, Synthesis and Bioactivity
Marine Drugs, 2022 A marine natural product possesses a diverse and unique scaffold that contributes to a vast array of bioactivities. Tricyclic guanidine alkaloids are a type of scaffold found only in marine natural products.
Nur Zahirah Abd Rani +4 more
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Path energy of two kinds of special tricyclic graphs
Journal of Hebei University of Science and Technology, 2020 Aiming at the problem that there are many kinds of tricyclic graphs and the complexity of path matrix is high, the path energy of two kinds of tricyclic graphs with or without pendant vertices was studied by means of matrix analysis, the existence ...
Wenjing LI, Yanling SHAO
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