Formylation of carbohydrates and the evolution of synthetic routes to artificial oligosaccharides and glycoconjugates

2000 ◽  
Vol 72 (9) ◽  
pp. 1577-1588 ◽  
Author(s):  
Alessandro Dondoni
Keyword(s):  
Amino Acid ◽  
Heterocyclic Ring ◽  
Synthetic Methods ◽  
Formyl Group ◽  
Alternative Synthesis ◽  
Synthetic Utility ◽  
Highly Effective ◽  
Synthetic Routes ◽  
Galactosyl Ceramide

A highly effective method for the synthesis of formyl C-glycosides is described via addition of 2-lithiothiazole or 2-lithiobenzothiazole to sugar lactones, deoxygenation of the resulting ketols, and releasing of the formyl group from the heterocyclic ring. The synthetic utility of these sugar aldehydes is demonstrated by the development of synthetic methods to more elaborate C-glycosides. These include various (1-6)-C-disaccharides and some higher oligomers up to a C,C,C,C-pentasaccharide; C-glycosyl amino acid isosteres of N-glycosyl asparagines; the methylene isostere of β-Δ-galactosyl ceramide; linear and cylic (2-1)-ketoside oligomers. An alternative synthesis of ethylene-bridged glycosyl asparagine isosteres is illustrated by the use of ethynyl C-glycosides as starting materials.

Synthetic Routes to 2-Iminothiazolidines: State-of-the-Art 2006-2020

2020 ◽  
Vol 24 (24) ◽  
pp. 2823-2844
Author(s):  
Aditya Bhattacharyya
Keyword(s):  
State Of The Art ◽  
Biological Significance ◽  
Review Article ◽  
Synthetic Methods ◽  
Pharmacological Properties ◽  
Cyclic Molecules ◽  
Synthetic Routes

: Multiheteroatom-containing small-sized cyclic molecules such as 2- iminothiazolidines are often found to possess beneficial pharmacological properties. In this review article, the biological significance of 2-iminothiazolidines is discussed and the literature reports published in the last 15 years spanning from 2006 to 2020 describing various preparative routes to access 2-iminothiazolidine derivatives have been categorically and chronologically described. The notable synthetic methods discussed here involve ringexpansion transformations of nonactivated and activated aziridines, thiiranes, epoxides, and other miscellaneous reactions.

scholarly journals Approaches towards the synthesis of 5-aminopyrazoles

2011 ◽  
Vol 7 ◽  
pp. 179-197 ◽  
Author(s):  
Ranjana Aggarwal ◽  
Vinod Kumar ◽  
Rajiv Kumar ◽  
Shiv P Singh
Keyword(s):  
Biological Properties ◽  
Synthetic Methods ◽  
Medicinal Properties ◽  
Synthetic Routes

The biological and medicinal properties of 5-aminopyrazoles have prompted enormous research aimed at developing synthetic routes to these heterocyles. This review focuses on the biological properties associated with this system. Various synthetic methods developed up to 2010 for these compounds are described, particularly those that involve the reactions of β-ketonitriles, malononitrile, alkylidenemalononitriles and their derivatives with hydrazines, as well as some novel miscellaneous methods.

Identification of an indole–triazole–amino acid conjugate as a highly effective antifungal agent

MedChemComm ◽  
2015 ◽  
Vol 6 (7) ◽  
pp. 1352-1359 ◽  
Author(s):  
Kalpana Pawar ◽  
Anshuman Yadav ◽  
Parteek Prasher ◽  
Sahil Mishra ◽  
Balwinder Singh ◽  
...  
Keyword(s):  
Amino Acid ◽  
Antifungal Agent ◽  
Antifungal Activities ◽  
Amino Acid Conjugate ◽  
Highly Effective ◽  
Acid Conjugate

Compounds constructed by the grafting of amino acid and triazole with an indole moiety were synthesized and investigated for antifungal activities wherein one of the compounds gave highly promising results.

The conformational restriction of synthetic peptides, including a malaria peptide, for use as immunogens

1989 ◽  
Vol 323 (1217) ◽  
pp. 565-572 ◽  
Keyword(s):  
Hydrogen Bond ◽  
Plasmodium Falciparum ◽  
Amino Acid ◽  
Hydrogen Bonds ◽  
Synthetic Peptides ◽  
Synthetic Methods ◽  
Amide Hydrogen ◽  
Conformational Restriction ◽  
Conformationally Restricted ◽  
New Strategy

A new strategy is advanced for the conformational restriction of peptidyl immunogens. Our approach is to replace putative amide-amide hydrogen bonds with covalent hydrogen-bond mimics. Because on average every other amino acid in a protein engages in this bond, the syntheses of diversely shaped peptides can be contemplated. Synthetic methods for introducing a potential hydrogen-bond mimic into a peptide with α-helical potential is reported and the structural consequences are discussed. The replacement of the hydrogen bond with a chemical link will modify as well as shape the peptide. To explore the consequences of these changes, a potential synthetic vaccine for malaria, the repeating tetrapeptide Asn-Pro-Asn-Ala, was conformationally restricted. Antibodies to the shaped malarial peptide showed a strong cross reaction with Plasmodium falciparum sporozoites.

ChemInform Abstract: Synthetic Routes to Benzosuberone-Based Fused- and Spiro-Heterocyclic Ring Systems

ChemInform ◽  
2016 ◽  
Vol 47 (15) ◽  
pp. no-no
Author(s):  
Thoraya A. Farghaly ◽  
Sobhi M. Gomha ◽  
Kamal M. Dawood ◽  
Mohamed R. Shaaban
Keyword(s):  
Heterocyclic Ring ◽  
Ring Systems ◽  
Synthetic Routes

scholarly journals Intrinsically Elastic Organic Semiconductors (IEOSs)

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6130
Author(s):  
Fei Liu ◽  
Xueling Hou ◽  
Ben-Lin Hu ◽  
Run-Wei Li
Keyword(s):  
Organic Synthesis ◽  
Organic Semiconductors ◽  
Structural Engineering ◽  
Electronic Devices ◽  
Synthetic Methods ◽  
Chemical Structures ◽  
Mechanical And Electrical Properties ◽  
Wearable Electronic ◽  
Synthetic Routes ◽  
Wearable Electronic Devices

Elastic semiconductors are becoming more and more important to the development of flexible wearable electronic devices, which can be prepared by structural engineering design, blending, and the intrinsic elastification of organic semiconductors (intrinsically elastic organic semiconductor, IEOS). Compared with the elastic semiconductors prepared by structural engineering and blending, the IEOS prepared by organic synthesis has attracted numerous attentions for its solution processability and highly tunable chemical structures. For IEOSs, reasonable designs of synthetic routes and methods are the basis for realizing good mechanical and electrical properties. This brief review begins with a concise introduction of elastic semiconductors, then follows with several synthetic methods of IEOSs, and concludes the characteristics of each method, which provides guidance for the synthesis of IEOSs in the future. Furthermore, the properties of IEOSs are involved from the aspects of electrical, mechanical properties, and the applications of the IEOSs in elastic electronic devices. Finally, the challenge and an outlook which IEOSs are facing are presented in conclusion.

scholarly journals Direct Synthesis and Applications of Solid Silylzinc Reagents

2021 ◽  
Author(s):  
Ramesh Rasappan ◽  
Revathi Chandrasekaran ◽  
Feba Thomas Pulikkottil ◽  
Krishna Suresh
Keyword(s):  
Detrimental Effect ◽  
Functional Group ◽  
Direct Synthesis ◽  
Cross Coupling ◽  
Synthetic Methods ◽  
Synthetic Method ◽  
General Applicability ◽  
Alkyl Aryl ◽  
Synthetic Utility ◽  
First Time

The increased synthetic utility of organosilanes motivates researchers to develop a milder and more practical synthetic methods. Silylzinc reagents, which are typically the most functional group tolerant, are notoriously difficult to synthesize because they are obtained by a pyrophoric reaction of silyllithium, particularly Me3 SiLi itself prepared by the reaction of MeLi and disilane. Furthermore, the dissolved LiCl in silylzinc may have a detrimental effect. A synthetic method that can avoid silyllithium and involves a direct synthesis of silylzinc reagents from silyl halides is arguably the simplest and economical strategy. We describe for the first time, the direct synthesis of PhMe2 SiZnI and Me3 SiZnI reagents by employing a coordinating TMEDA ligand, as well as single crystal XRD structures. Importantly, they can be obtained as solid and stored for longer periods of time. We demonstrate their significance in cross-coupling of various free alkyl/aryl/alkenyl carboxylic acids with broader functional group tolerance and API derivatives. The general applicability and efficiency of solid Me3 SiZnI are shown in a wide variety of reactions including alkylation, arylation, allylation, 1,4-addition, acylation and more.

Sign in / Sign up

Export Citation Format

Share Document