Geminal acylation of α-heterosubstituted cyclohexanones and their ketals

2010 ◽  
Vol 88 (11) ◽  
pp. 1118-1124 ◽  
Author(s):  
Ian R. Pottie ◽  
Sheldon N. Crane ◽  
Anna Lee Gosse ◽  
David O. Miller ◽  
D. Jean Burnell
Keyword(s):  
Significant Extent ◽  
Amberlyst 15 ◽  
Pinacol Rearrangement ◽  
Diastereomeric Mixture ◽  
Derivatives Of ◽  
Geminal Acylation

Geminal acylation of derivatives of cyclohexanone with Br, Cl, F, and OCH3 in the α position, and of their corresponding dimethyl ketals, could not be accomplished to a significant extent following published procedures. The transformation was accomplished in two steps. The initial BF3·Et2O-mediated reaction with 1,2-bis(trimethylsilyloxy)cyclobutene gave a cyclobutanone product as a mixture of diastereomers. Only with 2-chlorocyclohexanone did this occur with good diastereoselectivity. Then, pinacol rearrangement of the diastereomeric mixture mediated by Amberlyst-15 in benzene provided the heterosubstituted spirocyclic diketone.

One-pot synthesis of new category of 2-aryl-quinazolinones using OImDSA as an efficient heterocyclic medium

2021 ◽  
Vol 24 ◽  
Author(s):  
Abdolrahman Keyhani ◽  
Mohammad Nikpassand ◽  
Leila Zare Fekri ◽  
Hassan Kefayati
Keyword(s):  
Ionic Liquid ◽  
Reaction Time ◽  
Synthesis Method ◽  
Reaction Times ◽  
Isatoic Anhydride ◽  
One Pot ◽  
Amberlyst 15 ◽  
Three Component Reaction ◽  
Wide Range ◽  
Derivatives Of

Background: Dihydroquinazolinone derivatives are an important family of fused heterocyclic shows a wide range of biological, medicinal and pharmacological properties such as anti-tumor, anti-biotic, diuretic, analgesic, antihypertonic, anti-pyretic, anti-depressant, anti-histamine and vasodilation activities. Introduction: So far some acid catalysts, e.g.; p-toluenesulfonic acid, silica sulfuric acid, zinc(II) perfluorooctanoate, gallium(III) triflate, ionic liquid, Al(H2PO4)3, I2, montmorillonite K-10, Amberlyst-15, Al/Al2O3 and Fe3O4 nanoparticles, have been reported to accomplish this three component reaction. Some of these methods have drawbacks such as toxic solvents and catalysts, long reaction time, the use of expensive catalysts and adverse yields. Method: A mixture of benzaldehydes (1mmol), isatoic anhydride (1 mmol), Glycine (1 mmol) and OImDSA (2 mL) were stirred at room temperature for the required reaction times (1-2 h). The progress of the reaction was monitored by TLC (EtOAc: petroleum ether 1:2). After completion of reaction, as indicated by TLC, the ionic liquid was separated by extraction with 2×15 mL of water. The solid residue was separated by recrystallization from EtOH. The pure products were collected in 86-97% yields. Results: Herein, in order to achieve a more efficient synthesis method, to deplete side effects, reduce reaction steps, increase efficiency and curtail reaction time, and also to continue our research on the synthesis of heterocyclic and pharmaceutical compounds. We wish to report the mild synthesis of some derivatives of 2-aryl-quinazolin-4(1H)-ones from isatoic anhydride and Glycine using OImDSA Conclusion: In conclusion, we have developed a simple, green and efficient protocol for the synthesis of 2-aryl-quinazolin- 4(1H)-ones using OImDSA as an efficient and new procedure. Simplicity, easy practice, integrated with inexpensive, environmentally friendly and reusable ionic liquid are notable attributes of this new method. To the best of our knowledge, this is the first report for the synthesis of a new library of quinazolin-4(1H)-ones derived from Glycine as a natural substrate based on green chemistry conditions.

scholarly journals Antifilarial Activity of Constituents of Calophyllum inophyllum and their Derivatives

2013 ◽  
Vol 8 (6) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Jankiprasad ◽  
Gunaganti Naresh ◽  
Jyoti Gupta ◽  
Shailja M. Bhattacharya ◽  
Siron M. Rajendran ◽  
...  
Keyword(s):  
Meriones Unguiculatus ◽  
Acid Mixture ◽  
Calophyllum Inophyllum ◽  
Amide Derivatives ◽  
Diastereomeric Mixture ◽  
Drug Discovery Program ◽  
Antifilarial Activity ◽  
Derivatives Of

Elephantiasis is a classic sign of late-stage lymphatic filariasis. Although the infection can be treated with drugs, the chronic conditions may not be curable by currently available antifilarial drugs. In continuation of our drug discovery program, we identified potent antifilarial activity in a calophyllic acid and isocalophllic acid mixture, which was isolated from the leaves of Calophyllum inophyllum. The mixture inhibited the motility of adult Brugia malayi worms and microfilariae stage parasites at a concentration of 15.6 μg/mL with an IC50 of 2.1 and 5.5 μg/mL, respectively, in in vitro studies. The diastereomeric mixture also exhibited moderate in vivo antifilarial activity in the jird ( Meriones unguiculatus) model. A few derivatives of calophyllic acid and isocalophyllic acid were prepared and one of the amide derivatives turned out to be the most promising compound against the adult (MIC: 3.9 and IC50: 0.32 μg/mL) and microfilariae stage (MIC:1.9 and IC50: 0.26 μg/mL) parasites with a high selectivity index. The amide derivative has superior activity than the parent natural product, as well as the standard antifilarial drug, ivermectin.

Physical Properties of TCNQ Salts with N-Methyl Derivatives of Pyridine

1982 ◽  
Vol 85 (1) ◽  
pp. 257-263 ◽  
Author(s):  
A. Graja ◽  
M. Przybylski ◽  
B. Butka ◽  
R. Swietlik
Keyword(s):  
Physical Properties ◽  
Methyl Derivatives ◽  
Derivatives Of

Diorganyl Derivatives of Tellurium(IV) (σ-Telluranes of R 2 TeX 2 Type)

2002 ◽  
Vol 23 (2) ◽  
pp. 125-207 ◽  
Author(s):  
Igor D. Sadekov ◽  
Alexander V. Zakharov ◽  
Alexander A. Maksimenko
Keyword(s):  
Derivatives Of
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