41013-99-4Relevant academic research and scientific papers
One-pot synthesis, biological evaluation, and docking study of new chromeno-annulated thiopyrano[2,3-c]pyrazoles
Parmar, Bhagyashri D.,Sutariya, Tushar R.,Brahmbhatt, Gaurangkumar C.,Parmar, Narsidas J.,Kant, Rajni,Gupta, Vivek K.,Murumkar, Prashant R.,Sharma, Mayank Kumar,Yadav, Mange Ram
, p. 639 - 657 (2016/07/12)
Abstract: A one-pot synthesis of new chromeno-annulated thiopyrano[2,3-c]pyrazoles has been achieved through a domino-Knoevenagel–hetero-Diels–Alder reaction after combining various pyrazol-5-thiones with O-alkenyloxy/alkynyloxy-salicylaldehydes/naphthaldehydes in a Br?nsted acidic ionic liquid, [Hmim]HSO4, methylimidazolium hydrogen sulphate, under microwave irradiation. The method is simple and in many cases the isolated products did not require further purification. The central pyranothiopyranyl cis-fusion was confirmed by 2D NMR NOESY and single-crystal X-ray analysis suggesting that the endo-E-Syn transition state would be the most favored pathway of the reaction. Many heterocycles of this new series were found active against six bacterial and two fungal strains. In addition, all the compounds possess good anti-oxidant activity with the ferric reducing anti-oxidant power value >100mmol/100g. All new structures were docked into active site of angiotensin I converting enzyme (ACE), assuming that the compounds possessed the anti-hypertensive activity potential on the basis of prediction of activity spectra of substances prediction results. Pyranyl ring oxygen in compound 9a forms two hydrogen bonds with HIS353 and HIS513 residues in the active site of the ACE having good G score (- 4.06) of this compound, comparable to that of the reference drug captopril (- 4.93). Graphical Abstract: [Figure not available: see fulltext.]
An efficient synthesis of some thiopyranopyrazole-heterocycles via domino reaction in a Bronsted acidic ionic liquid
Parmar, Narsidas J.,Parmar, Bhagyashri D.,Sutariya, Tushar R.,Kant, Rajni,Gupta, Vivek K.
supporting information, p. 6060 - 6064 (2015/01/08)
The thiopyrazole gave many new polycyclic thiopyranopyrazole-heterocycles when it was assembled with a variety of O-alkenylated/alkynylated salicylaldehydes and naphthaldehydes in Bronsted acidic ionic liquid, [Hmim]HSO4, via domino/Knoevenagel-hetero-Diels-Alder (DKHDA) reaction. The reaction is highly stereoselective and the work-up procedure required no chromatography of products in many cases.
Intramolecular 1,3-Dipolar Cycloadditions and Intramolecular Ene Reactions of 2-(Alkenyloxy)benzaldehyde Arylhydrazones
Shimizu, Tomio,Hayashi, Yoshiyuki,Kitora, Yoshitaka,Teramura, Kazuhiro
, p. 2450 - 2455 (2007/10/02)
2-(3-Aryl-2-propenyloxy)benzaldehyde (or 1-naphthaldehyde) arylhydrazones undergo an intramolecular cycloaddition reaction via their 1,3-dipolar tautomers, azomethine imines, to the alkenyl group.Initial cycloadducts were converted to dehydrogenated compounds under the reaction conditions.On the other hand, introduction of cyano or ethoxycarbonyl groups instead of the aryl group into 3-position of the ortho propenyloxy group gave 3-cyanomethyl-4-chromanone arylhydrazones or the corresponding ethoxycarbonyl derivatives, respectively.The formation of these hydrazones was interpreted in terms of intramolecular ene reaction.The course of the reactions depends on the nature of the alkenyl substituents.
