Domino Suzuki-Miyaura Cross-Coupling and Oxidative Condensation Reaction: An Approach Towards Synthesis of Phenanthridine and Its Analogues

10.26434/chemrxiv.14754996.v1 ◽

2021 ◽

Author(s):

Yasin Nuree ◽

Jayanta Ray

Keyword(s):

Mutagenic Activity ◽

Condensation Reaction ◽

Platinum Complex ◽

Cross Coupling ◽

Core Structure ◽

Synthetic Methods ◽

Dna Intercalation ◽

Oxidative Condensation ◽

The Core ◽

Anti Tumor Activity

Phenanthridines belong to a very important class of nitrogen containing heterocylic compounds and constitute core structure of many natural alkaloids such as trisphaeridine and nitidine. Quarternarybenzo[c]phenanthridine alkaloids (QBA) represented by sanguinarine(SA), chelerythrine (CHE), and fagaronine (FA) exhibit antifungal and nematocidal properties and also serve as the core structure of broad range of medicinally active molecules showing anti-tumor activity, anti-viral property, anti-neoplastic or mutagenic activity through DNA-intercalation. Phenanthridines are also utilized for the synthesis of compounds of therapeutic interests such as anticancer platinum complex typified by phenanthriplatin antibacterial, anti-infectives, antprotozoal, antituberculosis, antitrypanosomiasis compounds. Although conventional synthetic methods towards their development showed their own advantages, they generally involved either multistep processes with low yield, or starting materials which are not readily available or requirement of prefunctionalization. Hence herein we present the development of an efficient and convenient synthetic methodology towards these versatile compounds. <br>

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Double Ring-Closing Approach for the Synthesis of 2,3,6,7-Substituted Anthracene Derivatives

10.26434/chemrxiv.12052647.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

Birgit Meindl ◽

Katharina Pfennigbauer ◽

Berthold Stöger ◽

Martin Heeney ◽

Florian Glöcklhofer

Keyword(s):

Wittig Reaction ◽

Condensation Reaction ◽

Synthetic Methods ◽

Anthracene Derivative ◽

Double Ring ◽

Mild Conditions ◽

Wide Range ◽

Anthracene Derivatives

Anthracene derivatives have been used for a wide range of applications and many different synthetic methods for their preparation have been developed. However, despite continued synthetic efforts, introducing substituents in some positions has remained difficult. Here we present a method for the synthesis of 2,3,6,7-substituted anthracene derivatives, one of the most challenging anthracene substitution patterns to obtain. The method is exemplified by the preparation of 2,3,6,7-anthracenetetracarbonitrile and employs a newly developed, stable protected 1,2,4,5-benzenetetracarbaldehyde as the precursor. The precursor can be obtained in two scalable synthetic steps from 2,5-dibromoterephthalaldehyde and is converted into the anthracene derivative by a double intermolecular Wittig reaction under very mild conditions followed by a deprotection and intramolecular double ring-closing condensation reaction. Further modification of the precursor is expected to enable the introduction of additional substituents in other positions and may even enable the synthesis of fully substituted anthracene derivatives by the presented approach.<br>

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Transition-Metal-Free Synthetic Strategies for the Cross-Coupling Reactions in Water: A Green Approach

Current Green Chemistry ◽

10.2174/2213346107999201006193653 ◽

2020 ◽

Vol 07 ◽

Author(s):

Tanmay Chatterjee ◽

Nilanjana Mukherjee

Keyword(s):

Transition Metal ◽

Organic Solvents ◽

Aqueous Media ◽

Cross Coupling ◽

Transition Metal Catalysts ◽

Synthetic Methods ◽

Coupling Reactions ◽

Organic Transformations ◽

Green Approach ◽

Dehydrogenative Coupling

Abstract: A natural driving force is always working behind the synthetic organic chemists towards the development of ‘green’ synthetic methodologies for the synthesis of useful classes of organic molecules having potential applications. The majority of the essential classes of organic transformations, including C-C and C-X (X = heteroatom) bond-forming crosscoupling reactions, cross dehydrogenative-coupling (CDC) mostly rely on the requirement of transition-metal catalysts and hazardous organic solvents. Hence, the scope in developing green synthetic strategies by avoiding the use of transitionmetal catalysts and hazardous organic solvents for those important and useful classes of organic transformations is very high. Hence, several attempts are made so far. Water being the most abundant, cheap, and green solvent in the world; numerous synthetic methods have been developed in an aqueous medium. In this review, the development of transitionmetal- free green synthetic strategies for various important classes of organic transformations such as C-C and C-X bondforming cross-coupling, cross dehydrogenative-coupling, and oxidative-coupling in an aqueous media is discussed.

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Indexicality of Grammar: The Case of Japanese Transgender Speakers

The Oxford Handbook of Language and Sexuality ◽

10.1093/oxfordhb/9780190212926.013.16 ◽

2019 ◽

Author(s):

Hideko Abe

Keyword(s):

Gender Identity ◽

Gender Identity Disorder ◽

Grammatical Gender ◽

Core Structure ◽

Subject Positions ◽

Transgender Identity ◽

The Core ◽

History Of ◽

History Of Scholarship ◽

Grammatical Structures

This article discusses how the intersection of grammatical gender and social gender, entwined in the core structure of language, can be analyzed to understand the dynamic status of selfhood. After reviewing a history of scholarship that demonstrates this claim, the discussion analyzes the language practices of transgender individuals in Japan, where transgender identity is currently understood in terms of sei-dōitsusei-shōgai (gender identity disorder). Based on fieldwork conducted between 2011 and 2017, the analysis reveals how individuals identifying with sei-dōitsusei-shōgai negotiate subject positions by manipulating the specific indexical meanings attached to grammatical structures.

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Solvent-free and efficient synthesis of bicyclic 2-pyridone derivatives for endoplasmic reticulum imaging

Organic Chemistry Frontiers ◽

10.1039/d1qo00350j ◽

2021 ◽

Author(s):

Xiaoyun Ran ◽

Qian Zhou ◽

Jin Zhang ◽

Shanqiang Wang ◽

Gui Wang ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Citric Acid ◽

Core Structure ◽

Solvent Free ◽

Efficient Synthesis ◽

The Core ◽

Catalyst Free ◽

Synthesis Approach ◽

Ethylenediamine Derivatives

Started from citric acid (CA) and ethylenediamine derivatives, a solvent-free, catalyst-free and highly yield synthesis approach for bicyclic 2-pyridones was presented. Continuing to modify the core structure, a series of...

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