Coumarins can be subdivided into two categories: (1) benzo-α-pyrone commonly called as coumarins (2) benzo-ϒ-pyrones called as chromones or flavanoids, differs only in the position of carbonyl group on the heterocyclic system. 1: 2-H CHROMEN-2-ONE COUMARIN Some important compounds isolated from coumarin are Warfarin, Acenocoumarol, Armillarisin A, Novobiocin, Clorobiocin, Hymecromone etc.
some mannich base of 5-methyl-[(2-oxo-2H-chromen-3-yl) carbonyl]-2,4-dihydro-3H-pyrazol-3-one (Fig.
20) by using conventional and non conventional (microwave) techniques.
Ethyl 2-oxo-2H-chromene-3-carboxylate was prepared by cyclization of salicylaldehyde with diethylmalonate in presence of catalytic amount of piperidine.
Reaction of this ester compound with hydrazine hydrate in ethanol formed 2-oxo-2H-chromene-3-carbohydrazide.
Activity of other compounds indicated that the presence of an additional fused benzene ring between the C-5` and C-6` positions inhibited the antibacterial activity towards ) compared to in Potato Dextrose Broth medium (PDB).
Appropriate volumes of tested compounds were added to produce concentrations ranging from 10 to 100μg/m L. 12) and (Fig.13) showed good activity as antifungals compared to the antifungal ability of fluconazole, which was used as a standard drugs. 12 FIG.13 4-Heteroaryl-coumarin-3-carbaldehydes Streptomycin was used as standard anti-bacterial drug and ketoconazole was used as standard anti-fungal drug. 17) had activity equal to that of standard drug ketoconazole (31.25 μg/m L) against ntiinflammatory and analgesic activity: Parmar V et al synthesized 4-methyl coumarin derivatives 7,8-dihydroxy-3-ethoxycarbonyl methyl -4-methylcoumarin (DHEMC) and 7,8-diacetoxy-3 - ethoxycarbonylmethyl - 4 - methylcoumarin (DAEMC) (Fig.Therefore, the condensation of pyrazolone with formaldehyde (60%) and various aromatic primary amines resulted in the formation the corresponding Mannich base derivatives.Antiinflammatory activity was evaluated by carageenan induced paw oedema in albino rats.Environmental conditions and seasonal changes can influence the occurrence in diverse parts of the plant .Although most of the natural coumarins in existence have been isolated from the higher plants, some members have been discovered in microorganisms.Specifically, coumarin-3-sulfonamides and carboxamides were reported to exhibit selective cytotoxicity against mammalian cancer cell lines.The C4-substituted aryloxymethyl, arylaminomethyl, and dichloroacetamidomethyl coumarins, along with the corresponding 1-azacoumarins, have been demonstrated to be potential anti-microbial and anti-inflammatory agents.All the synthesized compounds showed activity against both gram positive and gram negative bacteria but lesser activity compared to standard drug. 9 Patel et al synthesized some 4-aryl-2,6-di(coumarin-3-yl)pyridines by the reaction of 3-coumarinoyl methyl pyridinium salts with1-[2H-1-benzopyran-2-on-3-yl]-3-aryl-prop-2-ene-1-ones in the presence of ammonium acetate and acetic acid under the Krohnke reaction conditions (Fig. All the synthesized compounds were screened for antimicrobial activity.None of the compounds showed activity against either in the coumarin nucleus or in the phenyl ring did not affect the antibacterial activity much more and all the compounds have the same activity.19) by using Pechman condensation of pyrogallol with ethyl acetoacetate by introduction of an ethoxycarbonylmethyl group at C-3 position. Both were examined on the inflammatory process induced by lipopolysaccharide (LPS) in activated primary rat microglial cultures by Anna Rita Togna et al and thromboxane were inhibited in the presence of 100µM of DHEMC and DAEMC.Their experimentation showed that 4-methyl coumarin derivatives can modulate inflammatory pathways in microglial cells, probably by acting at the protein expression level.
Comments Thesis On Coumarins
New 3,4-Annelated Coumarin Derivatives Synthesis.
Annelated coumarin systems; Enamino and imino tautomeric forms;. p 23–25, PhD thesis, Univeristy of Helsinki, HelsinkiGoogle Scholar.…
A Review of Coumarin Derivatives in Pharmacotherapy of.
Of particular interest in breast cancer chemotherapy, some coumarins and their active metabolite 7-hydroxycoumarin. Most reviews classify coumarins according to whether particular compounds are simple coumarins e.g. PhD thesis.…
Ring-closing-metathesis-based synthesis of annellated.
Ring-closing-metathesis-based synthesis of annellated coumarins from 8-allylcoumarins. Christiane Schultze and Bernd Schmidt*.…
SYNTHESIS OF COUMARINS AND CHROMONES.
Thesis of compounds containing either the benzo-a-pyrone or the benzo-y-. reaction for the synthesis of coumarins Clayton? found that different phenols.…
COUMARINS AN OVERVIEW OF MEDICINAL CHEMISTRY.
Coumarins have attracted considerable attention of medicinal chemists and. PhD Thesis, Dublin City University, Dublin, Ireland, 1999.…
Synthesis of coumarins by ring-closing metathesis* - De Gruyter
This method allows for convenient access to a variety of coumarins substituted. thesis by ring-opening metathesis polymerizations ROMP 1 and step-growth.…
Coumarin Chemical and Pharmacological Profile - JAPS
Alfa-pyrones to which the coumarins belong and the benzo-gama-pyrones, of which the. Ojala T. PhD Thesis, University of Helsinki, Helsinki, Finland. 2001.…
Recent Advances in Transition-Metal-Catalyzed Synthesis of.
Priyanka et al. Review. Syn thesis. Recent Advances in Transition-Metal-Catalyzed Synthesis of. Coumarins. Priyanka. Rajesh Kumar Sharma.…