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1.
Org Biomol Chem ; 22(16): 3109-3185, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38529599

RESUMO

Iodine-containing molecules, especially hypervalent iodine compounds, have gained significant attention in organic synthesis. They are valuable and sustainable reagents, leading to a remarkable surge in their use for chemical transformations. One such hypervalent iodine compound, phenyliodine bis(trifluoroacetate)/bis(trifluoroacetoxy)iodobenzene, commonly referred to as PIFA, has emerged as a prominent candidate due to its attributes of facile manipulation, moderate reactivity, low toxicity, and ready availability. PIFA presents an auspicious prospect as a substitute for costly organometallic catalysts and environmentally hazardous oxidants containing heavy metals. PIFA exhibits remarkable catalytic activity, facilitating an array of consequential organic reactions, including sulfenylation, alkylarylation, oxidative coupling, cascade reactions, amination, amidation, ring-rearrangement, carboxylation, and numerous others. Over the past decade, the application of PIFA in synthetic chemistry has witnessed substantial growth, necessitating an updated exploration of this field. In this discourse, we present a concise overview of PIFA's applications as a 'green' reagent in the domain of synthetic organic chemistry. A primary objective of this article is to bring to the forefront the scientific community's awareness of the merits associated with adopting PIFA as an environmentally conscientious alternative to heavy metals.

2.
Carbohydr Res ; 534: 108974, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37922684

RESUMO

A solvent catalysed and metal catalyst-free Groebke-Blackburn-Bienayame three component reaction (GBB-3CR) has been developed for the synthesis of 2-(ß-D-glycal-1-yl)-3-N-alkylamino-1-azaindolizines and 2-alkyl/aryl/heteroaryl-3-N-alkylamino-1-azaindolizines. The modified GBB reaction protocol is highly efficient, versatile, atom economic and has been performed in hexafluoroisopropanol (HFIP) without any added catalyst. The GBB-3CR showed high tolerance for a large no of substrates in term of aldehydes, differently substituted 2-aminopyridines and isocyanides without being affected by the presence of electron donating and electron withdrawing substituents at either aldehydes or 2-aminopyridines.


Assuntos
Imidazóis , Piridinas , Solventes , Metais , Aminopiridinas , Aldeídos
3.
Org Biomol Chem ; 21(47): 9398-9409, 2023 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-37982163

RESUMO

Globally, human papillomavirus (HPV) infection is the leading cause of mortality associated with cervical cancer, oral cancer (oropharyngeal), and head and neck squamous cell carcinoma (HNSCC). It is essential to explore anti-cancer drugs against life-threatening HPV infections. Aiming to search for potentially better anticancer agents, a small library of ß-C-glycosylated methylidene succinimides have been synthesized under bulk and mechanical grinding conditions using the Wittig olefination reaction. Thus, the reaction of different 2,3,4,6-tetra-O-benzyl-C-glycosyl aldehydes with N-aryl/alkyl maleimides in the presence of PPh3 at 25 °C under bulk and mechanical grinding conditions results in the formation of stereochemically defined (E)-3-(2,3,4,6-tetra-O-benzyl-C-glycosylmethylidene)-N-alkyl/phenyl succinimides, which upon debenzylation with 1 M BCl3 in DCM at -78 °C lead to the synthesis of (E)-3-(C-glycosylmethylidene)-N-alkyl/phenyl succinimides in good to excellent yields. The developed methodology is efficient and environmentally benign because there is no use of organic solvents, and the products are obtained in a stereochemically defined form and in high yields. The aqueous solubility of all synthesized ß-C-glycosylated methylidene succinimides makes them potential candidates for the evaluation of their different biological activities. In the present work, the synthesized glycosylated alkylidine succinimides were subjected to an in-silico molecular docking study against the E6 oncoprotein of high-risk type HPV16, which is responsible for the inactivation of the tumor suppressor p53 protein. Analysis of the molecular docking data revealed that the synthesized compounds are effective inhibitors of HPV infection, which is the cause of oral, head and neck, and cervical cancer. In comparison with the positive control 5-FU, an anti-cancer drug used in chemotherapy, more than fifteen compounds were found to be better E6 protein inhibitors.


Assuntos
Antineoplásicos , Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Proteínas Oncogênicas Virais , Neoplasias do Colo do Útero , Feminino , Humanos , Carcinoma de Células Escamosas/metabolismo , Simulação de Acoplamento Molecular , Solventes , Antineoplásicos/farmacologia
4.
ACS Omega ; 6(17): 11248-11259, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-34056280

RESUMO

We have developed an efficient methodology for the synthesis of (2R,3S,4R)-2-hydroxymethyl-3,4-dihydroxy-6-aryl-7-aroylchromanes in which the chirality at the C-2, C-3, and C-4 positions is being drawn from C-glucopyranosyl aldehyde, which in turn can be efficiently synthesized from d-glucose. Thus, the synthesis starts with the transformation of sugar aldehyde into 1-(E-1-arylpropenon-3-yl)-3,4,6-tri-O-benzyl-d-glucals using Claisen-Schmidt type condensation reaction with different acetophenones and then to 1,2-disubstituted glucals via Pd(II)-catalyzed cross dehydrogenative coupling reaction, which in turn has been efficiently converted into (2R,3S,4R)-chromanes via 6π-electrocyclization and in situ dehydrogenative aromatization.

5.
Carbohydr Res ; 500: 108236, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33516073

RESUMO

A protocol based on Passerini multi-component reaction has been developed for facile, efficient and atom economical synthesis of a small library of twenty potential bioactive (2R)-2-(d-glycopyranosyl)-2-acyloxyacetamides using perbenzylated d-glycopyranosyl aldehydes, substituted isocyanides and different aliphatic/aromatic carboxylic acids. All twenty synthesized d-glycopyranosyl α-acyloxy amides, commonly known as depsipeptides were unambiguously identified on the basis of their spectral (IR, 1H, 13C NMR, COSY, HSQC, NOESY and HRMS) data analysis.


Assuntos
Depsipeptídeos/síntese química , Depsipeptídeos/química , Estrutura Molecular , Estereoisomerismo
6.
J Assoc Physicians India ; 60: 54-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23409427

RESUMO

Quadricuspid aortic valve is a rare congenital heart defect usually detected by echocardiography or at the time of aortic valve surgery. Preoperative recognition of this abnormality has clinical significance because it is frequently associated with other congenital cardiac abnormalities and anomalies of coronary origin. We report a case of quadricuspid aortic valve, which was detected preoperatively by transthoracic echocardiography and was associated with severe aortic regurgitation.


Assuntos
Insuficiência da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/anormalidades , Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia , Ecocardiografia , Feminino , Humanos , Pessoa de Meia-Idade
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