Merging strong and weak coordination motifs in the integrative self-sorting of a 5-component trapezoid and scalene triangle

2013 ◽  
Vol 11 (34) ◽  
pp. 5592 ◽  
Author(s):  
Manik Lal Saha ◽  
Jan W. Bats ◽  
Michael Schmittel
2021 ◽  
Author(s):  
Shun-Ze Zhan ◽  
Wei Chen ◽  
Ji Zheng ◽  
Seik Weng Ng ◽  
Dan Li

Five luminescent polymorphic aggregates of trinuclear Cu(I)-pyrazolate, namely [anti-Cu3L3]2 (1), [syn-Cu3L3·C2H5OH]2 (2), [anti-Cu3L3·C2H5OH]n (3), [anti-Cu3L3·0.5C7H8]n (4) and [syn-Cu3L3·C8H10]n (5) (HL = 4-(pyridin-4-ylthio)-3,5-dimethyl-1H-pyrazole), were reported. The trimeric Cu3L3 fragments present syn-...


2017 ◽  
Vol 73 (9) ◽  
pp. 703-709 ◽  
Author(s):  
Shayne Sorenson ◽  
Marina Popova ◽  
Atta M. Arif ◽  
Lisa M. Berreau

Metal–flavonolate compounds are of significant current interest as synthetic models for quercetinase enzymes and as bioactive compounds of importance to human health. Zinc–3-hydroxyflavonolate compounds, including those of quercetin, kampferol, and morin, generally exhibit bidentate coordination to a single ZnII center. The bipyridine-ligated zinc–flavonolate compound reported herein, namely bis(μ-4-oxo-2-phenyl-4H-chromen-3-olato)-κ3 O 3:O 3,O 4;κ3 O 3,O 4:O 3-bis[(2,2′-bipyridine-κ2 N,N′)zinc(II)] bis(perchlorate), {[Zn2(C15H9O3)2(C10H8N2)2](ClO4)2} n , (1), provides an unusual example of bridging 3-hydroxyflavonolate ligation in a dinuclear metal complex. The symmetry-related ZnII centers of (1) exhibit a distorted octahedral geometry, with weak coordination of a perchlorate anion trans to the bridging deprotonated O atom of the flavonolate ligand. Variable-concentration conductivity measurements provide evidence that, when (1) is dissolved in CH3CN, the complex dissociates into monomers. 1H NMR resonances for (1) dissolved in d 6-DMSO were assigned via HMQC to the H atoms of the flavonolate and bipyridine ligands. In CH3CN, (1) undergoes quantitative visible-light-induced CO release with a quantum yield [0.004 (1)] similar to that exhibited by other mononuclear zinc–3-hydroxyflavonolate complexes. Mass spectroscopic identification of the [(bpy)2Zn(O-benzoylsalicylate)]+ ion provides evidence of CO release from the flavonol and of ligand exchange at the ZnII center.


2010 ◽  
Vol 132 (45) ◽  
pp. 15933-15935 ◽  
Author(s):  
Kingsuk Mahata ◽  
Manik Lal Saha ◽  
Michael Schmittel

Author(s):  
Ahmed A. Baz

Abstract Background To describe the findings of the dynamic upper limb arterial and venous duplex in the assessment of vascular compression in cases of VTOS. This study was conducted on 58 patients with VTOS; they were evaluated by dynamic duplex examination. Results Vascular compression was subdivided into a venous compression that was detected in (84.4%, n = 49), arterial compression that was seen in (1.7%, n = 1), and combined arterial and venous compression that was present in (13.7%, n = 8); bilateral compression was existing in (94.4%, n = 55), compression at the scalene triangle was seen in (1.7%, n = 1), at the costo-clavicular space was seen in (91.3%, n = 53), and at the retro-pectoral space was depicted in (8.6%, n = 5). Complicated arterial compression was detected in (1.7%, n = 1), whereas venous complications were seen in (6.8%, n = 4). Conclusion Dynamic duplex ultrasound offered a simple, noninvasive, and quick technique that can help in the evaluation of the vascular thoracic outlet syndrome without exposure to ionizing radiation or contrast media administration like that in CT; nevertheless, it is done with the patient in the upright position, thus avoiding the high false-negative results associated with the supine position that is used in the CT and MRI studies.


2019 ◽  
Vol 3 (3) ◽  
pp. 225
Author(s):  
Fadhli Zul Fauzi ◽  
A. A. Gede Brahmantya Murti ◽  
Laili Alfiati Imamah ◽  
Nimas Hapsari

This article aims to examine the issue of infrastructure development in Papua Province, Indonesia. This article specifically discusses the problems confronted during the process of infrastructure development in Jayapura and the challenges in expanding them. The method used in this study is the qualitative method with a case study approach, wherein the infrastructure development case selected is the Papua Bangkit Stadium and Holtekamp Bridge located in Jayapura. Both infrastructure development cases serve as sample cases that show the extent of infrastructure development impact in Papua, and the issues that were confronted, starting from the development process up to the expansion. The study results indicate that although previous studies have shown positive correlation between development and welfare, in reality, there are several problems occurring in Papua’s infrastructure development. Preparedness of human resources, cultural issues, and weak coordination between every level of regional government institution, these are the main problems in Papua’s infrastructure development. This article is expected to assist in resolving the issues found in Papua’s infrastructure development, and to provide recommendations for resolving those issues.


2020 ◽  
Author(s):  
Hojoon Park ◽  
jin-quan yu

<div>Cycloaddition reactions provide an expeditious route to construct ring systems in a highly convergent and stereoselective manner. For a typical cycloaddition reaction to occur, however, the installation of multiple reactive functional groups (π-bonds, leaving group, etc.) are required within the substrates, compromising the overall efficiency or scope of the cycloaddition reaction. Here, we report a palladium-catalyzed [3+2] reaction that utilizes C(sp<sup>3</sup>)–H activation to generate the three-carbon unit for formal cycloaddition with maleimides. We implemented a strategy where the initial C(sp<sup>3</sup>)–H activation/olefin insertion would trigger a relayed, second remote C(sp<sup>3</sup>)–H activation to complete a formal [3+2] cycloaddition. The diastereoselectivity profile of this reaction resembles that of a typical pericyclic cycloaddition reaction in that the relationships between multiple stereocenters are exquisitely controlled in a single reaction. The key to success was the use of weakly coordinating amides as the directing group, as undesired Heck or alkylation pathways were preferred with other types of directing groups. The use of the pyridine-3-sulfonic acid ligands is critical to enable C(sp<sup>3</sup>)–H activation directed by this weak coordination. The method is compatible with a wide range of amide substrates, including lactams, which lead to novel spiro-bicyclic products. The [3+2] product is also shown to undergo a reductive desymmetrization process to access chiral cyclopentane bearing multiple stereocenters with excellent enantioselectivity.</div>


Author(s):  
Mutmainnah HS Dimo ◽  
Syaikhul Falah ◽  
Arius Kambu

The research objective was to evaluate the administration of regional property in the Sarmi Regency Government. The administrative aspects that were studied included the aspects of bookkeeping, inventory and reporting. Qualitative and quantitative methods are used to answer the research formulation. The research object consisted of three Regional Apparatus Organizations (OPD), including the Public Works Office, the Health Office and the Education Office. The interviewed informants are treasurers of goods. The interviewed informants were managers of regional property in three regional apparatus organizationsThe results of the research show that the Sarmi Regency Government has not fully implemented asset administration in accordance with the Minister of Home Affairs Regulation No. 19 of 2016. It is the only aspect of bookkeeping that has the highest value or has implemented regulations. Furthermore, the reporting and inventory aspects have not been said to have carried out regulatory orders.The results of this research resulted in the findings of several obstacles, namely: misuse of assets, weak coordination, lack of human resources to handle assets, and limited incentives for asset managers.


2018 ◽  
Author(s):  
Besem Beteck ◽  
John Eidt ◽  
Bradley Grimsley

Arterial thoracic outlet syndrome (TOS) is the least common form of TOS in adults. It is an entity that is associated with bony anomalies resulting in chronic subclavian artery compression. Most patients with arterial TOS are young adults presenting either with limb-threatening upper extremity ischemia or chronic symptoms suggestive of arterial insufficiency involving the extremity. Initial diagnostic evaluation involves chest radiography, which may reveal cervical or anomalous first rib. Catheter-based arteriography has a diagnostic as well as therapeutic role. Magnetic resonance angiography and computed tomographic angiography, which are readily available, can be used in surgical planning. Treatment involves revascularization of the extremity, subsequent first rib resection, and possible reconstruction of the subclavian artery. This review contains 4 figures, 1 table and 45 references Key Words: arterial complication, brachial thromboembolectomy, cervical rib, costoclavicular space, first rib resection, pectoralis minor space, scalene triangle, subclavian artery stenosis, thoracic outlet syndrome


2020 ◽  
Vol 26 (69) ◽  
pp. 16450-16454
Author(s):  
Qingqing Bu ◽  
Rositha Kuniyil ◽  
Zhigao Shen ◽  
Elżbieta Gońka ◽  
Lutz Ackermann
Keyword(s):  

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