scholarly journals Zinc Iodide Catalyzed Synthesis of Trisubstituted Allenes from Terminal Alkynes and Ketones

ACS Omega ◽  
2021 ◽  
Vol 6 (36) ◽  
pp. 23329-23346
Author(s):  
Leandros P. Zorba ◽  
Eunate Egaña ◽  
Enrique Gómez-Bengoa ◽  
Georgios C. Vougioukalakis
Keyword(s):  
Terminal Alkynes ◽  
Zinc Iodide

Nickel/Zinc Iodide Co-catalytic Asymmetric [2+2] Cycloaddition Reactions of Azabenzonorbornadienes with Terminal Alkynes

2017 ◽  
Vol 360 (3) ◽  
pp. 427-431 ◽  
Author(s):  
Jingchao Chen ◽  
Xin Xu ◽  
Zhenxiu He ◽  
Hongyu Qin ◽  
Weiqing Sun ◽  
...  
Keyword(s):  
Cycloaddition Reactions ◽  
Terminal Alkynes ◽  
Nickel Zinc ◽  
Catalytic Asymmetric ◽  
Zinc Iodide

The Reaction of Brain Structures with OsO4-Zinc-Iodide Stain

1971 ◽  
Vol 29 ◽  
pp. 272-273
Author(s):  
Werner J. Niklowitz
Keyword(s):  
Electron Microscope ◽  
Structural Changes ◽  
Mossy Fiber ◽  
Toxic Metal ◽  
Staining Technique ◽  
Brain Structures ◽  
Oxidase Inhibitor ◽  
Fiber Layer ◽  
Hippocampal Tissue ◽  
Zinc Iodide

After intoxication of rabbits with certain substances such as convulsant agents (3-acetylpyridine), centrally acting drugs (reserpine), or toxic metal compounds (tetraethyl lead) a significant observation by phase microscope is the loss of contrast of the hippocampal mossy fiber layer. It has been suggested that this alteration, as well as changes seen with the electron microscope in the hippocampal mossy fiber boutons, may be related to a loss of neurotransmitters. The purpose of these experiments was to apply the OsO4-zinc-iodide staining technique to the study of these structural changes since it has been suggested that OsO4-zinc-iodide stain reacts with neurotransmitters (acetylcholine, catecholamines).Domestic New Zealand rabbits (2.5 to 3 kg) were used. Hippocampal tissue was removed from normal and experimental animals treated with 3-acetylpyridine (antimetabolite of nicotinamide), reserpine (anti- hypertensive/tranquilizer), or iproniazid (antidepressant/monamine oxidase inhibitor). After fixation in glutaraldehyde hippocampal tissue was treated with OsO4-zinc-iodide stain and further processed for phase and electron microscope studies.

Cell Reactivity Pattern of the Guinea Pig Cecal Mucosa Evidenced by the ZIO Technique

1982 ◽  
Vol 40 ◽  
pp. 50-51
Author(s):  
Juan Mora-Galindo ◽  
Jorge Arauz-Contreras
Keyword(s):  
Guinea Pig ◽  
Phase Contrast ◽  
Osmium Tetroxide ◽  
Cell Types ◽  
Cell Reactivity ◽  
Transmission Electron ◽  
Neural Tissues ◽  
Maturation Stages ◽  
Zinc Iodide ◽  
Cecal Mucosa

The zinc iodide-osmium tetroxide (ZIO) technique is presently employed to study both, neural and non neural tissues. Precipitates depends on cell types and possibly cell metabol ism as well.Guinea pig cecal mucosa, already known to be composed of epithelium with cells at different maturation stages and lamina propria which i s formed by morphologically and functionally heterogeneous cell population, was studied to determine the pat tern of ZIO impregnation. For this, adult Guinea pg cecal mucosa was fixed with buffered 1.2 5% g 1 utara 1 dehyde before incubation with ZIO for 16 hours, a t 4°C in the dark. Further steps involved a quick sample dehydration in graded ethanols, embedding in Epon 812 and sectioning to observe the unstained material under a phase contrast light microscope (LM) and a transmission electron microscope (TEM).

Synthesis of Novel 1,2,3-Triazole Derivatives of Isocoumarins and 3,4-Dihydroisocoumarin with Potential Antiplasmodial Activity In Vitro

2020 ◽  
Vol 16 ◽  
Author(s):  
Lucas da Silva Santos ◽  
Matheus Fillipe Langanke de Carvalho ◽  
Ana Claudia de Souza Pinto ◽  
Amanda Luisa da Fonseca ◽  
Julio César Dias Lopes ◽  
...  
Keyword(s):  
Triazole Ring ◽  
Antiplasmodial Activity ◽  
World Health ◽  
Dipolar Cycloaddition ◽  
Terminal Alkynes ◽  
The World ◽  
Ic50 Values ◽  
Derivatives Of ◽  
Active Substances

Background: Malaria greatly affects the world health, having caused more than 228 million cases only in 2018. The emergence of drug resistance is one of the main problems in its treatment, demonstrating the urge for the development of new antimalarial drugs. Objective: Synthesis and in vitro antiplasmodial evaluation of triazole compounds derived from isocoumarins and a 3,4- dihydroisocoumarin. Method: The compounds were synthesized in 4 to 6-step reactions with the formation of the triazole ring via the Copper(I)-catalyzed 1,3-dipolar cycloaddition between isocoumarin or 3,4-dihydroisocoumarin azides and terminal alkynes. This key reaction provided compounds with an unprecedented connection of isocoumarin or 3,4-dihydroisocoumarin and the 1,2,3-triazole ring. The products were tested for their antiplasmodial activity against a Plasmodium falciparum chloroquine resistant and sensitive strains (W2 and 3D7, respectively). Results: Thirty-one substances were efficiently obtained by the proposed routes with an overall yield of 25-53%. The active substances in the antiplasmodial test displayed IC50 values ranging from 0.68-2.89 μM and 0.85-2.07 μM against W2 and 3D7 strains, respectively.

On-Surface Synthesis of Carbon-Based Scaffolds and Nanomaterials Using Terminal Alkynes

2015 ◽  
Vol 48 (7) ◽  
pp. 2140-2150 ◽  
Author(s):  
Florian Klappenberger ◽  
Yi-Qi Zhang ◽  
Jonas Björk ◽  
Svetlana Klyatskaya ◽  
Mario Ruben ◽  
...  
Keyword(s):  
Terminal Alkynes ◽  
Carbon Based

Importance of bases on the copper-catalyzed oxidative homocoupling of terminal alkynes to 1,4-disubstituted 1,3-diynes

2012 ◽  
Vol 53 (41) ◽  
pp. 5559-5561 ◽  
Author(s):  
Xinjiang Niu ◽  
Chunju Li ◽  
Jian Li ◽  
Xueshun Jia
Keyword(s):  
Terminal Alkynes ◽  
Oxidative Homocoupling
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