Thursday, August 18, 2016

A Simple and Highly Efficient Procedure for One-Pot Synthesis of 2- Azetidinones Using 3,5-Dinitrobenzoyl Chloride

Author(s):

Alireza Darvishi, Maaroof Zarei and Mohammad Reza AkhgaraPages 645-650 (6)

Abstract:


One-pot synthesis of 2-azetidinones has efficiently been carried out in excellent yields by treatment of imines and substituted acetic acids with 3,5-dinitrobenzoyl chloride in the presence of triethylamine. The method is remarkably convenient and pure products were obtained by simple crystallization.

Keywords:

β -Lactam, 2-Azetidinone, Staudinger reaction, 3, 5-Dinitrobenzoyl chloride, Ketene, Imine.

Affiliation:

Department of Chemistry, Faculty of Science, Kerman Branch, Islamic Azad University, Kerman, Iran; and Department of Chemistry, College of Sciences, Hormozgan University, Bandar Abbas 71961, Iran.


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Copper and Iron-assisted Palladium-catalyzed Direct Arylation of Azoles with Arylboronic Acids under Ligand and Base-free Conditions

Author(s):

Xiang-Mei Wu and Qiu-Xian ShenPages 668-673 (6)

Abstract:


The direct arylation of azoles with arylboronic acids is effectively promoted by PdCl2 in the presence of copper and iron salts under ligand and base-free conditions. This reaction can be applied to heterocycles such as benzothiazole, benzoxazole, 1-methylbenzimidazole and 4,5-dimethylthiazole with moderate to good yields.

Keywords:

Palladium, copper, iron, arylation, arylboronic acid.

Affiliation:

Department of Chemistry, College of Science, Lishui University, Lishui, Zhejiang 323000, China.


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1,2,4-Triazoles: A Review of Synthetic Approaches and the Biological Activity

Author(s):

Suresh Maddila, Ramakanth Pagadala and Sreekanth B. JonnalagaddaPages 693-714 (22)

Abstract:


1,2,4-Triazoles and their derivatives have a distinct place in the field of medicinal and pharmaceutical chemistry. These are used as lead compounds for the synthesis of numerous heterocyclic compounds which possess diverse biological activities and play pivotal roles. This review covers the latest literature and knowledge on the synthetic procedures for various triazoles derivatives, their activities and pharmacological applications.

Keywords:

1, 2, 4-Traizole, synthesis, biological activity, review.

Affiliation:

School of Chemistry & Physics, University of KwaZulu-Natal, Westville Campus, P Bag X 54001, Durban 4000, SOUTH AFRICA.


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Efficient Synthesis of 6-O-methyl-scutellarein from Scutellarin via Selective Methylation

Author(s):

Min-Zhe Shen, Zhi-Hao Shi, Nian-Guang Li, Hao -Tang, Qian-Ping Shi, Yu-Ping Tang, Jian-Ping Yang and Jin-Ao DuanPages 733-737 (5)

Abstract:


Scutellarin (1) possesses distinguished efficacy in the clinical therapy of cerebral infarction, coronary heart disease, and angina pectoris. Scutellarin (1) is readily converted in vivo, therefore, synthetic methods for the construction of its metabolites will be very important in the near future. In this work, an efficient and first synthetic method for 6-O-methyl- scutellarein (3), one metabolite of scutellarin in vivo, is developed. Dichlorodiphenylmethane in diphenyl ether is used firstly to protect the dihydroxy groups at C-6 and C-7 in scutellarein (2). Then, benzyl bromide is used to selectively protect the hydroxy groups at C-4' and C-7 in 10. 6-O-Methyl-scutellarein (3) is obtained in high yield through seven steps.

Keywords:

6-O-methyl-scutellarein, metabolite, scutellarin, synthesis, regioselective protection.

Affiliation:

Jiangsu Key Laboratory for High Technology of TCM Formulae Research, Nanjing University of Chinese Medicine, Nanjing 210023, P.R. China.


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Synthesis of bis(indolyl)methanes Catalyzed by Triethylborane

Author(s):

J. Pablo Garcia Merinos, Heraclio Lopez Ruiz, Yliana Lopez and Susana RojasPages 332-336 (5)

Abstract:


Triethylborane (TEB) was found to be a mild, efficient, and acid catalyst in electrophilic substitution reaction of indoles with aldehydes compounds to afford the corresponding bis(indolyl)methanes. Vibrindole A (5) and bis(indolyl)methanes derivatives 16 and 18 were synthesized using this methodology. Compound 16 is an intermediary in the synthesis of the natural bisindoles arsindoline B (2) and streptindole (6). The structure of vibrindole A (5) was unequivocally confirmed by a single crystal X-ray diffraction analysis.

Keywords:

Arsindoline B, bis(indolyl)methanes, indole, streptindole, triethylborane.

Affiliation:

Lima Area Academica de Quimica, Universidad Autonoma del Estado de Hidalgo, Carretera Pachuca-Tulancingo Km. 4.5, Mineral de La Reforma, Hidalgo, CP 42076, Mexico and Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, Ed.B-1, C.U., Morelia, Michoacan, 58030, Mexico.


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