scholarly journals Synthesis of stereoenriched piperidines via chemo-enzymatic dearomatization of activated pyridines

Author(s):  
Vanessa Harawa ◽  
Thomas Thorpe ◽  
James Marshall ◽  
Amelia Gilio ◽  
Rachel Heath ◽  
...  

The development of efficient and sustainable methods for the synthesis of nitrogen heterocycles is an important goal for the chemical industry. In particular, substituted chiral piperidines are prominent targets due to their prevalence in medicinally relevant compounds and their precursors. A potential biocatalytic approach to the synthesis of this privileged scaffold would be the asymmetric dearomatization of readily assembled activated pyridines. However, nature has yet to yield a suitable biocatalyst specifically for this reaction. Here, by combining chemical synthesis and biocatalysis, we present a general chemo-enzymatic approach for the asymmetric dearomatization of activated pyridines for the preparation of substituted piperidines with precise stereochemistry. The key step involves a stereoselective one-pot amine oxidase/ene imine reductase cascade to convert N-substituted tetrahydropyridines to stereo-defined 3- and 3,4-substituted piperidines. This chemo-enzymatic approach has proved useful for key transformations in the syntheses of the antipsychotic drugs Preclamol and OSU-6162, as well as for the preparation of two important intermediates in synthetic routes of the ovarian cancer monotherapeutic Niraparib.

2005 ◽  
Vol 9 (2) ◽  
pp. 179-194 ◽  
Author(s):  
Biao Yu ◽  
Zunyi Yang ◽  
Hongzhi Cao
Keyword(s):  

2020 ◽  
Vol 24 (21) ◽  
pp. 2475-2497
Author(s):  
Andrea Verónica Rodríguez-Mayor ◽  
German Jesid Peralta-Camacho ◽  
Karen Johanna Cárdenas-Martínez ◽  
Javier Eduardo García-Castañeda

Glycoproteins and glycopeptides are an interesting focus of research, because of their potential use as therapeutic agents, since they are related to carbohydrate-carbohydrate, carbohydrate-protein, and carbohydrate-lipid interactions, which are commonly involved in biological processes. It has been established that natural glycoconjugates could be an important source of templates for the design and development of molecules with therapeutic applications. However, isolating large quantities of glycoconjugates from biological sources with the required purity is extremely complex, because these molecules are found in heterogeneous environments and in very low concentrations. As an alternative to solving this problem, the chemical synthesis of glycoconjugates has been developed. In this context, several methods for the synthesis of glycopeptides in solution and/or solid-phase have been reported. In most of these methods, glycosylated amino acid derivatives are used as building blocks for both solution and solid-phase synthesis. The synthetic viability of glycoconjugates is a critical parameter for allowing their use as drugs to mitigate the impact of microbial resistance and/or cancer. However, the chemical synthesis of glycoconjugates is a challenge, because these molecules possess multiple reaction sites and have a very specific stereochemistry. Therefore, it is necessary to design and implement synthetic routes, which may involve various protection schemes but can be stereoselective, environmentally friendly, and high-yielding. This review focuses on glycopeptide synthesis by recapitulating the progress made over the last 15 years.


2020 ◽  
Vol 17 (6) ◽  
pp. 438-442
Author(s):  
Xiaofang Ma ◽  
Shunxi Li ◽  
Samrat Devaramani ◽  
Guohu Zhao ◽  
Daqian Xu

The elimination of volatile organic solvents in organic synthesis is the most important goal in “Green” chemistry. We report a simple, efficient and facile method for the addition of progargyl bromide to carbonyl compounds using Mg metal as a mediator under solvent-free conditions which could regioselectively generate homopropargyl alcohols efficiently in good to excellent yields. The procedure has advantages such as short reaction time, operationally simple, excellent product yields, high regioselectivity and organic solvent-free.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1214
Author(s):  
Sergey N. Podyachev ◽  
Rustem R. Zairov ◽  
Asiya R. Mustafina

The present review is aimed at highlighting outlooks for cyclophanic 1,3-diketones as a new type of versatile ligands and building blocks of the nanomaterial for sensing and bioimaging. Thus, the main synthetic routes for achieving the structural diversity of cyclophanic 1,3-diketones are discussed. The structural diversity is demonstrated by variation of both cyclophanic backbones (calix[4]arene, calix[4]resorcinarene and thiacalix[4]arene) and embedding of different substituents onto lower or upper macrocyclic rims. The structural features of the cyclophanic 1,3-diketones are correlated with their ability to form lanthanide complexes exhibiting both lanthanide-centered luminescence and magnetic relaxivity parameters convenient for contrast effect in magnetic resonance imaging (MRI). The revealed structure–property relationships and the applicability of facile one-pot transformation of the complexes to hydrophilic nanoparticles demonstrates the advantages of 1,3-diketone calix[4]arene ligands and their complexes in developing of nanomaterials for sensing and bioimaging.


2018 ◽  
Vol 58 (5) ◽  
pp. 1458-1462 ◽  
Author(s):  
Alexander J. Boddy ◽  
Dominic P. Affron ◽  
Christopher J. Cordier ◽  
Emma L. Rivers ◽  
Alan C. Spivey ◽  
...  

2014 ◽  
Vol 43 (11) ◽  
pp. 4565-4572 ◽  
Author(s):  
Jason M. Lynam ◽  
Lucy M. Milner ◽  
Neetisha S. Mistry ◽  
John M. Slattery ◽  
Sally R. Warrington ◽  
...  

2014 ◽  
Vol 50 (44) ◽  
pp. 5837-5839 ◽  
Author(s):  
Man Pan ◽  
Yao He ◽  
Ming Wen ◽  
Fangming Wu ◽  
Demeng Sun ◽  
...  

An efficient one-pot chemical synthesis of snake venom toxin Mambalgin-1 was achieved using an azide-switch strategy combined with hydrazide-based native chemical ligation.


1978 ◽  
Vol 31 (5) ◽  
pp. 1095 ◽  
Author(s):  
DE Cowley ◽  
CC Duke ◽  
AJ Liepa ◽  
JK Macleod ◽  
DS Letham

The structures of the major stable plant metabolites of the cytokinins zeatin and 6-benzylaminopurine have been confirmed by synthesis to be 7- and 9-β-D-glucopyranosides. The small quantities of metabolites initially isolated (< 100 μg) precluded assignment of the glucose ring size or configuration of the anomeric linkage so that synthesis of both the furanose and pyranose forms of 7-β-D- and 9-β-D-glucosylzeatin and 6-benzylaminopurine was undertaken which allowed direct u.v., m.s. and t.l.c. comparison with the metabolites. Numerous synthetic routes to the unusual 7-glucosides of the two cytokinins were explored, the most successful utilizing a one-pot pyrimidine ring closure of an imidazole derivative to afford directly in high yield the required 7-glucosides of zeatin and 6-benzylaminopurine.


e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
Adam Kiersnowski ◽  
Maria Trelinska-Wlazlak ◽  
Justyna Dolega ◽  
Jacek Piglowski

AbstractThis article describes simple preparation methods of poly(methyl methacrylate) (PMMA)/synthetic montmorillonite nanocomposites by single-step insitu polymerizations. Compatibility between PMMA and the silicate was ensured by an addition of (3-acrylamidepropyl) trimethylammonium chloride (AAPTMA). The work also compares how different synthetic routes, namely emulsion and solution polymerization, affect the structure as well as thermal and mechanical properties of obtained nanocomposites. The results of structural investigations clearly show, that both the techniques lead to intercalated nanocomposites, but emulsion polymerization allows more effective deflocculating and intercalating of the clay with acrylic copolymers. The addition of small amounts of layered silicates causes an increase in thermal stability and stiffness of the materials. It is demonstrated that at 5 wt. % of the filler, the temperature of 10 % weight loss was shifted up by nearly 50 K in comparison to the neat PMMA. In the same sample, the Young’s modulus of the material was found to be increased by 26 %.


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