The Experts below are selected from a list of 432 Experts worldwide ranked by ideXlab platform
Weiran Yang - One of the best experts on this subject based on the ideXlab platform.
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a formal 3 2 annulation reaction of propargyl Sulfonium compounds and n ylides access to pyrrolo 2 1 a quinolines pyrrolo 2 1 a phthalazines and indolizines
Organic and Biomolecular Chemistry, 2020Co-Authors: Jing Zheng, Hua Liu, Weiran YangAbstract:A sequential [3 + 2] annulation of prop-2-ynylSulfonium salt and N-ylides was developed, leading to the formation of a series of pyrrolo[2,1-a]quinolines, pyrrolo[2,1-a]phthalazines and indolizines. The protocol featured the simultaneous one-pot formation of three new C-C bonds in moderate yields under mild conditions. In this reaction, the prop-2-ynylSulfonium salts acted as the C2 synthons and sulfide served as the leaving group. The resultant products could serve as useful precursors for the synthesis of diverse chemical compounds.
Mario B Pinto - One of the best experts on this subject based on the ideXlab platform.
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synthesis of aza and thia spiroheterocycles and attempted synthesis of spiro Sulfonium compounds related to salacinol
Carbohydrate Research, 2007Co-Authors: Wang Chen, Mario B PintoAbstract:The synthesis of aza- and thia-spiroheterocycles and the attempted synthesis of spiro Sulfonium compounds related to salacinol are described. The binding of the nanomolar inhibitor swainsonine to Drosophila Golgi alpha-mannosidase II (dGMII) involves a large contribution of interactions between the six-membered ring of the inhibitor and the hydrophobic pocket within the enzyme active site. Salacinol, a naturally occurring Sulfonium ion, is one of the active principles in the aqueous extracts of Salacia reticulata that are traditionally used in Sri Lanka and India for the treatment of diabetes. Spiro aza- and thia-heterocycles and a spiro analogue of salacinol were designed with the expectation that the hydrocarbon portions would make hydrophobic contributions to binding. The former sets of compounds were synthesized successfully but the salacinol analogue proved to be elusive. The stereochemistry of the final compounds was determined by means of 1D-NOESY experiments. The aza- and thia-heterocycles were not effective inhibitors of Golgi alpha-mannosidase II or human maltase glucoamylase.
Jing Zheng - One of the best experts on this subject based on the ideXlab platform.
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a formal 3 2 annulation reaction of propargyl Sulfonium compounds and n ylides access to pyrrolo 2 1 a quinolines pyrrolo 2 1 a phthalazines and indolizines
Organic and Biomolecular Chemistry, 2020Co-Authors: Jing Zheng, Hua Liu, Weiran YangAbstract:A sequential [3 + 2] annulation of prop-2-ynylSulfonium salt and N-ylides was developed, leading to the formation of a series of pyrrolo[2,1-a]quinolines, pyrrolo[2,1-a]phthalazines and indolizines. The protocol featured the simultaneous one-pot formation of three new C-C bonds in moderate yields under mild conditions. In this reaction, the prop-2-ynylSulfonium salts acted as the C2 synthons and sulfide served as the leaving group. The resultant products could serve as useful precursors for the synthesis of diverse chemical compounds.
Robert G Carden - One of the best experts on this subject based on the ideXlab platform.
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trivalent Sulfonium compounds tscs tetrahydrothiophene based amphiphiles exhibit similar antimicrobial activity to analogous ammonium based amphiphiles
Bioorganic & Medicinal Chemistry Letters, 2021Co-Authors: Javier A Feliciano, Austin J Leitgeb, Cassandra L Schrank, Ryan A Allen, Kevin P C Minbiole, William M Wuest, Robert G CardenAbstract:Recent advances in the development of quaternary ammonium compounds (QACs) have focused on new structural motifs to increase bioactivity, but significantly less studied has been the change from ammonium- to Sulfonium-based disinfectants. Herein, we report the synthesis of structurally analogous series of quaternary ammonium and trivalent Sulfonium compounds (TSCs). The bioactivity profiles of these compounds generally mirror each other, and the antibacterial activity of Sulfonium-based THT-18 was found to be comparable to the commercial disinfectant, BAC. The development of these compounds presents a new avenue for further study of disinfectants to combat the growing threat of bacterial resistance.
B. Mario Pinto - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and conformational analysis of bicyclic Sulfonium salts. Structures related to the glycosidase inhibitor australine.
The Journal of Organic Chemistry, 2006Co-Authors: Nag S. Kumar, B. Mario PintoAbstract:The syntheses of eight Sulfonium compounds with structures related to the naturally occurring pyrrolizidine alkaloid, australine, in which the bridgehead nitrogen atom is replaced by a Sulfonium ion, are described. The synthetic strategy relies on the intramolecular attack of a cyclic thioether across a terminal double bond in the presence of a suitable electrophile. We postulate that these compounds, having a permanent positive charge on the sulfur atom, will mimic the highly unstable oxacarbenium ion transition state in a glycosidase-catalyzed hydrolysis reaction. The conformational preferences of these compounds, based on analysis of 1H−1H vicinal coupling constants and 1D-NOESY data, are attributed to both steric and electrostatic interactions. These compounds will be used in the study of structure−activity relationships with glycosidase enzymes.
