Parallel synthesis of meso-substituted corroles and meso-substituted [22]pentaphyrins(1.1.1.0.0) from diacyl-dipyrromethanes

2003 ◽  
Vol 07 (04) ◽  
pp. 239-248 ◽  
Author(s):  
Daniel T. Gryko ◽  
Mariusz Tasior ◽  
Beata Koszarna
Keyword(s):  
Functional Groups ◽  
Parallel Synthesis ◽  
New Method ◽  
Large Excess ◽  
Tertiary Amides ◽  
Moderate Yield ◽  
Made In

A new method was devised for the synthesis of 1,9-diacyldipyrromethanes - crucial intermediates in the synthesis of meso-substituted corroles and porphyrins with different substituents. The diacylodipyrromethanes formation involves acylation of dipyrromethanes with salts made in situ from POCl 3 and tertiary amides. This modified Vilsmeier approach gives higher yields and no concomitant formation of monoacyldipyrromethanes as compared with the Grignard route. Moreover, compounds possessing groups previously inaccessible ( CN , NO 2 etc.) can be synthesized. During optimization of the transformation of diacyldipyrromethanes into meso-substituted corroles it was found that if macrocyclization reaction mediated by DDQ is performed in the presence of large excess of pyrrole, meso-substituted [22]pentaphyrins(1.1.1.0.0) can be obtained in moderate yield. The currently described procedure constitutes a new method for the synthesis of these valuable porphyrinoids. Corroles possessing interesting, easy to transform, functional groups were obtained in 3-40% yield.

Reductive Cleavage of Secondary Sulfonamides: Converting Terminal Functional Groups into Versatile Synthetic Handles

2019 ◽  
Author(s):  
Patrick Fier ◽  
Suhong Kim ◽  
Kevin M. Maloney
Keyword(s):  
Functional Groups ◽  
Late Stage ◽  
Reductive Cleavage ◽  
Bioactive Molecules ◽  
General Method

Sulfonamides are pervasive in drugs and agrochemicals, yet are typically considered as terminal functional groups rather than synthetic handles. To enable the general late-stage functionalization of secondary sulfonamides, we have developed a mild and general method to reductively cleave the N-S bonds of sulfonamides to generate sulfinates and amines, components which can further react <i>in-situ</i> to access a variety of other medicinally relevant functional groups. The utility of this platform is highlighted by the selective manipulation of several complex bioactive molecules.

A new method for the in situ assay of α-glucosidase activity and inhibitor screening through an enzyme substrate-mediated DNA hybridization chain reaction

2019 ◽  
Vol 43 (24) ◽  
pp. 9458-9465
Author(s):  
Xiquan Yue ◽  
Lihong Su ◽  
Xu Chen ◽  
Junfeng Liu ◽  
Longpo Zheng ◽  
...  
Keyword(s):  
Small Molecule ◽  
Dna Hybridization ◽  
New Method ◽  
Hybridization Chain Reaction ◽  
Chain Reaction ◽  
Inhibitor Screening ◽  
Glucosidase Activity ◽  
Enzyme Substrate ◽  
In Situ Assay

The strategy is based on small molecule-mediated hybridization chain reaction.

Engaging with the science and politics of biodiversity futures: a literature review

2021 ◽  
pp. 1-8
Author(s):  
Carina Wyborn ◽  
Elena Louder ◽  
Mike Harfoot ◽  
Samantha Hill
Keyword(s):  
Human Life ◽  
Global Environmental Change ◽  
Life Forms ◽  
Trade Offs ◽  
Global Environmental ◽  
Science And Politics ◽  
Science Community ◽  
Impact On Biodiversity ◽  
Made In

Summary Future global environmental change will have a significant impact on biodiversity through the intersecting forces of climate change, urbanization, human population growth, overexploitation, and pollution. This presents a fundamental challenge to conservation approaches, which seek to conserve past or current assemblages of species or ecosystems in situ. This review canvases diverse approaches to biodiversity futures, including social science scholarship on the Anthropocene and futures thinking alongside models and scenarios from the biophysical science community. It argues that charting biodiversity futures requires processes that must include broad sections of academia and the conservation community to ask what desirable futures look like, and for whom. These efforts confront political and philosophical questions about levels of acceptable loss, and how trade-offs can be made in ways that address the injustices in the distribution of costs and benefits across and within human and non-human life forms. As such, this review proposes that charting biodiversity futures is inherently normative and political. Drawing on diverse scholarship united under a banner of ‘futures thinking’ this review presents an array of methods, approaches and concepts that provide a foundation from which to consider research and decision-making that enables action in the context of contested and uncertain biodiversity futures.

Direct amidation of acid fluorides using germanium amides

2021 ◽  
Author(s):  
Ardalan Hayatifar ◽  
Emily Elifritz ◽  
Molly Bloom ◽  
Kaitlyn Pixley ◽  
Chris Fennell ◽  
...  
Keyword(s):  
Functional Groups ◽  
New Method ◽  
New Methods ◽  
Acid Fluorides ◽  
Direct Amidation

Amide functional groups are an essential linkage that are found in peptides, proteins, and pharmaceuticals and new methods are constantly being sought for their formation. Here, a new method is...

A New Method of Finishing of Cotton Fabric by in Situ Synthesis of Silver Nanoparticles

2014 ◽  
Vol 53 (11) ◽  
pp. 4147-4155 ◽  
Author(s):  
Anna Bacciarelli-Ulacha ◽  
Edward Rybicki ◽  
Edyta Matyjas-Zgondek ◽  
Aleksandra Pawlaczyk ◽  
Malgorzata I. Szynkowska
Keyword(s):  
Silver Nanoparticles ◽  
Cotton Fabric ◽  
In Situ Synthesis ◽  
New Method

A Novel and Efficient Alkoxylselenenylation of Alkenes

2019 ◽  
Vol 41 (6) ◽  
pp. 1039-1039
Author(s):  
Yingguo Fang and Jie Yan Yingguo Fang and Jie Yan
Keyword(s):  
Room Temperature ◽  
Electrophilic Addition ◽  
New Method ◽  
Reaction Conditions ◽  
Selenium Species

A novel and efficient alkoxylselenenylation from alkenes, diselenides, and alcohols mediated by iodine is developed, with which a series of β-alkoxy selenides are synthesized. In this procedure, firstly, I2 reacts with diselenide to form in situ the active electrophilic selenium species RSeI, then following an electrophilic addition of it to alkenes provides β-alkoxy selenides with high regioselectivity and in good yields. This new method for achieving β-alkoxy selenides has some advantages over other methods such as using available and cheap iodine as the oxidizing species at room temperature, which makes this reaction has milder reaction conditions and simpler procedure.

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