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Coumarin - Wikipedia
General & Introductory Chemistry
Fais A. e al resynthesized coumarin- resveratrol hybrids by a traditional Perkin reaction carried out in refluxing dimethylsulfoxide (DMSO) between o-hydroxybenzaldehyde (or their methoxy substituted derivatives) and the corresponding aryl acetic acids, using dicyclohexylcarbodiimide (DCC) as dehydrating agent to investigate the structure activity relationship. Tyrosinase activity assays were performed with L-DOPA as substrate with slight modifications and activity of mushroom tyrosinase was determined by sectrophotometric technique. IC 50 values of these compounds were measured. The result showed that these compounds (figure 62) exhibited tyrosinase inhibitory activity. 3-(3’,4’,5’-trihydroxyphenyl - 6, 8 - dihydroxy coumarin was found to be the most potent compound (0.27mM) more than umbelliferone (0.42mM) used as a reference compound. The kinetic studies revealed that these compounds non-competitive tyrosine kinase inhibition and the number and the position of free hydroxyl groups play an important role in determining the activity.
CONCLUSION: In present review we focused on different derivatives of coumarin which were synthesized by various methods and their activities were studied. It can be concluded that coumarin ring is fused with other rings, a synergistic effect of both the rings in their biological activities were obtained, such compounds were exploited in development of various important molecule which provides scaffolds for drug development.
This review focus on therapeutic ..
Sashidhara KV et al. synthesized a series of novel coumarin bisindole heterocycles 51 (Fig. 39) and these compounds were evaluated for antihyperlipidemic activity in hyperlipidemic hamster model. In these compounds, as far as coumarin pharmacophore is considered, it revealed that the substitution at position 3 play a pivotal role and the presence of ethyl ester over methyl is preferred for pronounced activity. On the other hand, cursory look at the lower indole pharmacophore highlighted that the unsubstituted indoles have good activity profile compared to substituted indoles. Among twelve compounds tested, one compound having R = C2H5 and R1 = R2 = -H showed potent activity and was found to decrease the plasma triglyceride levels (TG) by 55%, total cholesterol (TC) by 20%, accompanied by an increase in HDL-C/TC ratio by 42% in hyperlipidemic rats to a greater degree than some of the reference statins.
Apart from the above works, the present review focuses on the recent research done on coumarins, which basically incudes the synthesis of therapeutically useful coumarins alongwith the SAR, so as to give an overview of essential structural features required for therapeutic activities. 3
A comprehensive review on synthesis and designing …
Some important compounds isolated from coumarin are Warfarin, Acenocoumarol, Armillarisin A, Novobiocin, Clorobiocin, Hymecromone etc. coumarin and its derivatives could be synthesized in laboratory by Pechmann reaction, perkin reaction, Reformatsky reaction and Knovenegal reaction. Coumarins have been under extensive studies for their versatile biodynamic activities, for example coumarins with phenolic hydroxyl group have the ability to scavenge reactive oxygen species and thus prevent the formation of 5- HETE and 5- HHT in arachadonic acid pathway of suppression of inflammation. Recent in vivo studies have revealed the role of coumarins in hepatotoxicity and also in depletion of cytochrome P450. Similarly 1-azacoumarins which is part of quinoline alkaloids are known for their diverse biological activity and recently, a 6- functionalized 1-aza coumarins are undergoing human clinical trials as an orally active antitumor drug in view of its farnesyl protein-inhibiting activity in the nanomolar range. Furthermore, several synthetic coumarins with a variety of pharmacophoric groups at C-3, C-4 and C-7 positions have been intensively screened for anti-microbial, anti-HIV, anti-cancer, lipidlowering, anti-oxidant, and anti-coagulation activities. Specifically, coumarin-3-sulfonamides and carboxamides were reported to exhibit selective cytotoxicity against mammalian cancer cell lines.
ABSTRACT: Fusion of a pyrone ring with a benzene nucleus gives rise to a class of heterocyclic compounds called Benzopyrones, of which two distinct types are recognized: (1) benzo-α-pyrone commomly called coumarins and (2) benzo-ϒ-pyrone called chromones or flavanoids, latter differing from former only in the position of the carbonyl group in heterocyclic system. Coumarins have attracted considerable attention of medicinal chemists and pharmacologists in recent years as they been demonstrated to bear various pharmacological activities like anti microbial, anti oxidant, anti inflammatory and analgesic, anti cancer, ulcerogenic, anti malarial, antihyperlipidemic, tyrosinase inhibitor, anti convulsant, anti-parkinsonian, antihepatitis, anticoagulant, cholinesterase inhibitor, vasorelaxant. This review focus on therapeutic importance of coumarins along with various methods of synthesis
04/04/2012 · Coumarin-based drugs: a patent review ..
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Psoralen - Wikipedia
Expert Opinion on Therapeutic Patents.
Psoralen (also called psoralene) is the parent compound in a family of natural products known as furocoumarins
Medicinal Significance of Coumarins: A Review - …
Oriental Journal of Chemistry is a peer reviewed quarterly research journal of pure and applied chemistry
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