scholarly journals When Hydrazonoyl Chlorides Meet Allenes: a Site- and Regio-Selective Copper(I)-Catalysed Approach to 5-Substituted Pyrazoles

Heterocycles ◽  
2021 ◽  
Vol 102 (10) ◽  
pp. 1995
Author(s):  
Giorgio Molteni ◽  
Stefano Baroni ◽  
Marco Manenti ◽  
Alessandra Silvani
Keyword(s):  
Hydrazonoyl Chlorides ◽  
A Site ◽  
Substituted Pyrazoles

Synthesis of 8,10-disubstituted-triazoloperimidines from (E)-3-(dimethylamino)-1-(8- phenyl-8H-[1,2,4]triazolo[4,3-a]perimidin-10-yl)prop-2-en-1-one and Their Antimicrobial Activity

2018 ◽  
Vol 15 (1) ◽  
pp. 126-136 ◽  
Author(s):  
Ghada S. Masaret ◽  
Thoraya A. Farghaly
Keyword(s):  
Antimicrobial Activity ◽  
Acetic Acid ◽  
Hydrazine Hydrate ◽  
Spectral Data ◽  
Organic Compounds ◽  
The Novel ◽  
Hydrazonoyl Chlorides ◽  
Elemental Analyses ◽  
Different Types ◽  
Substituted Pyrazoles

Aim and Objective: Enaminones belay to be extremely stable compounds and constitute a versatile group of salutary precursors for the synthesis of enormous classes of organic compounds. So, in this context, we synthesized a new enaminone, namely, (E)-3-(dimethylamino)-1-(8-phenyl-8H-[1,2,4]triazolo[4,3- a]perimidin-10-yl)prop-2-en-1-one (enaminone 2). Materials and Methods: The reaction of enaminone 2 with different types of hydrazonoyl chlorides or hydrazine hydrate afforded new substituted pyrazoles. Also, the reaction of enaminone with 6-amino-2- thioxopyrimidin-4-one in acetic acid under reflux produced 2-thioxopyridopyrimidinone derivative. The latter thione derivative reacts with hydrazonoyl chlorides to give pyridotriazolopyrimidines. 5-(8-Phenyl-8H- [1,2,4]triazolo[4,3-a]perimidin-10-yl)isoxazole was produced from the reaction of enaminone 2 with hydroxylamine. Results & Conclusion: The structure of all the novel perimidine derivatives was confirmed on the basis of spectral data and elemental analyses. The enaminone and the newly synthesized compounds were tested for their antimicrobial activity, and the results obtained revealed that some derivatives are more potent than the reference drugs used.

Synthesis of fully substituted pyrazoles from pyridinium 1,4-zwitterionic thiolates and hydrazonoyl chlorides via a [[3 + 3] − 1] pathway

2020 ◽  
Vol 18 (15) ◽  
pp. 2949-2955 ◽  
Author(s):  
Bin Cheng ◽  
Bian Bao ◽  
Wei Xu ◽  
Yuntong Li ◽  
Hui Li ◽  
...  
Keyword(s):  
Ring Contraction ◽  
Cascade Cyclization ◽  
Hydrazonoyl Chlorides ◽  
Substituted Pyrazoles ◽  
Extrusion Reaction

Pyrazoles were synthesized from pyridinium 1,4-zwitterionic thiolates and hydrazonoyl chlorides via an unusual [[3 + 3] − 1] pathway, involving a formal [3 + 3] cascade cyclization followed by a spontaneous ring-contraction/sulfur extrusion reaction.

Eels Under Standing Wave Conditions

1982 ◽  
Vol 40 ◽  
pp. 492-495
Author(s):  
O.L. Krivanek ◽  
J. TaftØ
Keyword(s):  
Standing Wave ◽  
Wave Conditions ◽  
Set Up ◽  
A Site ◽  
Complex Crystal

It is well known that a standing electron wavefield can be set up in a crystal such that its intensity peaks at the atomic sites or between the sites or in the case of more complex crystal, at one or another type of a site. The effect is usually referred to as channelling but this term is not entirely appropriate; by analogy with the more established particle channelling, electrons would have to be described as channelling either through the channels or through the channel walls, depending on the diffraction conditions.

Head Size and DNA Content in Bacteriophage T4

1972 ◽  
Vol 30 ◽  
pp. 200-201
Author(s):  
Fred Eiserling ◽  
A. H. Doermann ◽  
Linde Boehner
Keyword(s):  
Electron Microscopy ◽  
Dna Content ◽  
Bacteriophage T4 ◽  
Head Size ◽  
Virus Particles ◽  
Altered Protein ◽  
A Cell ◽  
Bacterial Viruses ◽  
A Site ◽  
Protein Shell

The control of form or shape inheritance can be approached by studying the morphogenesis of bacterial viruses. Shape variants of bacteriophage T4 with altered protein shell (capsid) size and nucleic acid (DNA) content have been found by electron microscopy, and a mutant (E920g in gene 66) controlling head size has been described. This mutant produces short-headed particles which contain 2/3 the normal DNA content and which are non-viable when only one particle infects a cell (Fig. 1).We report here the isolation of a new mutant (191c) which also appears to be in gene 66 but at a site distinct from E920g. The most striking phenotype of the mutant is the production of about 10% of the phage yield as “giant” virus particles, from 3 to 8 times longer than normal phage (Fig. 2).

Exploration-Stage Implementation Variation

2014 ◽  
Vol 222 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Stephanie Romney ◽  
Nathaniel Israel ◽  
Danijela Zlatevski
Keyword(s):  
Parent Training ◽  
Average Cost ◽  
Cost Savings ◽  
Training Group ◽  
Group Differences ◽  
Triple P ◽  
Community Based ◽  
Parent Training Program ◽  
A Site ◽  
The Cost

The present study examines the effect of agency-level implementation variation on the cost-effectiveness of an evidence-based parent training program (Positive Parenting Program: “Triple P”). Staff from six community-based agencies participated in a five-day training to prepare them to deliver a 12-week Triple P parent training group to caregivers. Prior to the training, administrators and staff from four of the agencies completed a site readiness process intended to prepare them for the implementation demands of successfully delivering the group, while the other two agencies did not complete the process. Following the delivery of each agency’s first Triple P group, the graduation rate and average cost per class graduate were calculated. The average cost-per-graduate was over seven times higher for the two agencies that had not completed the readiness process than for the four completing agencies ($7,811 vs. $1,052). The contrast in costs was due to high participant attrition in the Triple P groups delivered by the two agencies that did not complete the readiness process. The odds of Triple P participants graduating were 12.2 times greater for those in groups run by sites that had completed the readiness process. This differential attrition was not accounted for by between-group differences in participant characteristics at pretest. While the natural design of this study limits the ability to empirically test all alternative explanations, these findings indicate a striking cost savings for sites completing the readiness process and support the thoughtful application of readiness procedures in the early stages of an implementation initiative.

DISTRIBUTION OF STRAINS AT Fe2+A SITE IN THE THIOSPINEL FeSc2S4

1976 ◽  
Vol 37 (C6) ◽  
pp. C6-23-C6-28 ◽  
Author(s):  
L. BROSSARD ◽  
H. OUDET ◽  
P. GIBART
Keyword(s):  
A Site
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