‘In situ’ Generated ‘HCl’ - An Efficient Catalyst for Solvent-Free Hantzsch Reaction at Room Temperature: Synthesis of New Dihydropyridine Glycoconjugates (original) (raw)
Related papers
2014
An efficient Hantzsch synthesis of various substituted 1,4-dihydropyridines from an aldehyde, a β-dicarbonyl compound and ammonium acetate using p-toluenesulfonic acid in a solvent-free condition in the absence of any other co-catalyst is described. The process is simple and environmentally benign and the catalyst is commercially available and inexpensive. This method has the advantages of excellent yield (80-96%) and short reaction time (5-20 min.). Irradiation of a typical 1,4-dihydropyridine leads to the corresponding pyridine.
A Review: Alternative Methods of Preparing 1, 4- Dihydropyridine Derivatives by Hantzsch Reaction
Journal of Scientific Research
1, 4-dihydropyridines and its derivatives are an important class of heterocyclic scaffolds of low molecular weight. Dihydropyridines act as calcium-channel blockers. They have been used for the treatment of a variety of cardiovascular diseases due to their potential antihypertensive, anti-angina, vasodilator, and cardiac depressant activities. They show antibacterial, anticancer, anti-leishmanial, anticoagulant, anticonvulsant, anti-tubercular, antioxidant, antiulcer, and neuroprotective properties. The reaction to produce 1, 4-dihydropyridines (1, 4-DHPs) was reported by Arthur Hantzsch. This review article will throw light on some green attempts done to improve the synthesis of 1, 4-Dihydropyridine derivatives via Hantzsch reaction.
Rapid and cleaner synthesis of 1,4-dihydropyridines in aqueous medium
Heteroatom Chemistry, 2006
The present investigation deals with a novel water soluble Lewis acid complex, Zn[(L)proline]2 catalyzed Hantzsch 1,4-dihydropyridine derivatives syntheses in aqueous medium assisted by microwave irradiation. The microwave promoted syntheses in aqueous medium afforded moderate to excellent yield (up to 98%) within short reaction time and allowed the reaction to take place with low microwave power (200 W). This synthetic methodology provides easier separation of products and the catalyst exhibits recycling ability without loss of its catalytic activity up to five reaction cycles. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:267–271, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20197
Synthesis, Charecterisation and biological Evaluation of Novel Hantzsch 1,4-dihydropyridines
We report a library consisting of some novel Hantzsch dihydropyridines of biological interest as well as their synthesis and analysis. The important steps in the synthetic part were found to be Hantzsch reactions. The synthesized compounds were screened for their in vitro antibacterial activity against two gram-positive bacteria: Staphylococcus aureus and Bacillus subtilis. The title compounds did not exhibit potential antibacterial activity. Furthermore, compounds were subjected to in vitro cytotoxicity against Vero cells. Compounds exhibited weak, moderate, or high cytotoxicity. Compounds 9b, 9c, 9d, 9e, 9f, 9g exhibited potential cytotoxicity.