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Perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) was modified by ethylenediamine to obtain perylene-3,4,9,10-tetracarboxylic diimide (PTCDI). PTCDI as an initial core was used to bond coumarin derivatives. Successful conjugating of coumarin derivatives onto PTCDI was confirmed by Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H NMR), X-ray diffraction (XRD), and field emission scanning electron microscope (FE-SEM). XRD peaks of various samples showed that the crystalline structure of PTCDA retained during the modification processes. The morphology of the nanoparticles by FE-SEM showed that the dyes were fibrillar. Fluorescence microscopy was used to evaluate the fluorescence properties of the dyes. In order to determine the amount of absorption and reflection in the near-infrared region, NIR test was used in both white and black fields. High absorption on a white background and high reflection on a black background indicated the transparency of the dye in the near-infrared region. The synthesized dye was identified and reported as a cold dye.

A new aza-15-crown-5 derivative 1 bearing coumarin and hydrazone moieties was synthesized and characterized. The fluorescent sensing behavior and selectivity of 1 toward different metal ions in ethanol were investigated. There are 4-fold and 2-fold fluore

A new photosensitive polyoxometalate (POM) organic-inorganic hybrid compound has been prepared by covalently tethering coumarin moieties onto a Mn-Anderson cluster. This compound has been fully characterized by 1H NMR, 13C NMR, FTIR, and UV/Vis spectroscopy, and ESI-MS. This organic-inorganic hybrid compound can undergo reversible light-driven polymerization and this process has been characterized in detail. Polymerizing POMs: A new photosensitive polyoxometalate (POM) organic-inorganic hybrid compound has been prepared by covalently tethering coumarin moieties onto a Mn-Anderson cluster. This compound has been fully characterized by 1H NMR, 13C NMR, FTIR, and UV/Vis spectroscopy, and ESI-MS. This compound can undergo reversible light-driven polymerization (see scheme) and this process has been characterized in detail. Copyright

3-Acyl-4-hydroxy-2-oxo-2H-chromen derivatives 1a-d were condensed with (7-hydroxy-2-oxo-2H-chromen-4-yl)-acetic acid hydrazide 2, (4-methyl-2-oxo-2H-chromen-7-yloxy)-acetic acid hydrazide 3, and (7-hydrazinocarbonylmethoxy-2-oxo-2H-chromen-4-yl)-acetic acid hydrazide 4, to give corresponding 3-alkyl-1-[2-(7-hydroxy-2-oxo-2H-chromeno-4-yl)-acetyl]-1H-chromeno[4,3-c] pyrazole-4-one 5a-d, 3-alkyl-1-[2-(4-methyl-2-oxo-2H-chromeno-7-yloxy)-acetyl]-1H-chromeno[4,3-c] pyrazole-4-one 6a-d, and 1-{4-[(3-alkyl-1H-chromeno[4,3-c]pyrazole-4-one-1-yl)-carbonylmethyl] -2-oxo-2H-chromen-7-yloxy-acetyl}-3-alkyl-1H-chromeno[4,3-c]pyrazole-4-one 7a-d.

Newly designed coumarinyloxy acetamide derivatives (7a-7n) were synthesized in good yields and characterised by advanced spectroscopic studies and the XRD studies indicated that no polymorphism is observed in the molecules. Synthesized coumarinyloxy aceta

Abstract: A series of 21 coumarin hydrazide–hydrazone derivatives were designed, synthesized and evaluated potential cytotoxicity effects at 25 μg/mL for 48 h against liver cancer (HepG2) cell line in vitro. Then, seven out of 21 compounds with % cell via

We performed a biochemical screen against mTOR using in-house small molecule library. Two novel, structurally distinct hits were identified. Among them, a novel oxadiazole scaffold compound (2) suppressed the phosphorylation of both S6K1 and Akt1 in HeLa cells. Docking study suggested that 2 is ATP-competitive and shows a pi-pi interaction with Trp2239 and hydrogen bonds with Trp2239 and Thr2245. Through derivatization, a slightly more potent analogue (2a) was identified with IC50 of 9.6 μM. Our study provides a starting point for discovery of novel potent mTOR inhibitors.

A facile iron-catalyzed decarboxylative radical coupling of alkyl diacyl peroxides with coumarins or chromones has been developed, affording a highly efficient approach to synthesize a variety of α-alkylated coumarins and β-alkylated chromones. The reaction proceeded smoothly without adding any ligand or additive and provided the corresponding products containing a wide scope of functional groups in moderate to excellent yields. This protocol was highlighted by its high regioselectivity, readily available starting materials, and operational simplicity.

A series of bi-functional 7-hydroxycoumarin platinum(IV) complexes were synthesized, characterized, and evaluated for antitumor activities. The 7-hydroxycoumarin platinum(IV) complexes display moderate to effective antitumor activities toward the tested cell lines and show much potential in overcoming drug resistance of platinum(II) drugs. In reducing microenvironment, the title compounds could be reduced to platinum(II) complex accompanied with two equivalents of coumarin units. By a unique mechanism, the 7-hydroxycoumarin platinum(IV) complex attacks DNA via the released platinum(II) compound, meanwhile it also inhibits the activities of cyclooxygenase by coumarin fragment. This action mechanism might be of much benefit for reducing tumor-related inflammation in the progress of inhibiting tumor proliferation and overcoming cisplatin resistance. The incorporation of 7-hydroxycoumarin leads to significantly enhanced platinum accumulation in both whole tumor cells and DNA. The HSA interaction investigation reveals that the tested coumarin platinum(IV) compound could effectively combine with HSA via van der Waals force and hydrogen bond.

With an aim to develop novel heterocyclic hybrids as potent anticancer agents, we synthesized a series of coumarin-1,3,4-oxadiazole hybrids (7a-t) and evaluated for their inhibitory activity against the four physiologically relevant human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms CA I, CA II, CA IX and CA XII. The CA inhibition results clearly indicated that the coumarin-1,3,4-oxadiazole derivatives (7a-t) exhibited selective inhibition of the tumor associated isoforms, CA IX and CA XII over CA I and II isoforms. Among all, compound 7b, exhibited significant inhibition in lower micromolar potency against hCA XII, with a Ki of 0.16 μM and compound 7n, exhibited significant inhibition in lower micromolar potency against hCA IX, with a Ki of 2.34 μM respectively. Therefore, compound 7b and 7n could be the potential leads for development of selective anticancer agents by exhibiting a novel mechanism of action through hCA IX and XII inhibition.

Coumarinyl 1,3,4-oxadiazoles were synthesized from Schiff bases and acetic anhydride. All compounds were characterized by melting points and their structures confirmed by mass and 1 H and 13 C NMR spectrometry. These novel coumarinyl

Novel coumarin-tryptamine systems attached through a linker were synthesised and evaluated in vitro against acetylcholinesterase by the classical Ellman's test.

Alzheimer's disease (AD), a neurodegenerative disorder, is a serious medical issue worldwide with drastic social consequences. Inhibition of cholinesterase is one of the rational and effective approaches to retard the symptoms of AD and, hence, consistent efforts are being made to develop efficient anti-cholinesterase agents. In pursuit of this, a series of 19 acetamide derivatives of chromen-2-ones were synthesized and evaluated for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential. All the synthesized compounds exhibited significant anti-AChE and anti-BChE activity, with IC50 values in the range of 0.24–10.19 μM and 0.64–30.08 μM, respectively, using donepezil hydrochloride as the standard. Out of 19 compounds screened, 3 compounds, viz. 22, 40, and 43, caused 50% inhibition of AChE at 0.24, 0.25, and 0.25 μM, respectively. A kinetic study revealed them to be mixed-type inhibitors, binding with both the CAS and PAS sites of AChE. The above-selected compounds were found to be effective inhibitors of AChE-induced and self-mediated Aβ1–42 aggregation. ADMET predictions demonstrated that these compounds may possess suitable blood–brain barrier (BBB) permeability. Hemolytic assay results revealed that these compounds did not lyse human RBCs up to a thousand times of their IC50 value. MTT assays performed for the shortlisted compounds showed them to be negligibly toxic after 24 h of treatment with the SH-SY5Y neuroblastoma cells. These results provide insights for further optimization of the scaffolds for designing the next generation of compounds as lead cholinesterase inhibitors.

The invention discloses polyacid-coumarin photosensitive composites and a preparation method thereof. The technical scheme is that the preparation method comprises the following steps: coumarin molecular derivatives containing acyl chloride groups are prepared firstly; then the acyl chloride groups and amino groups are subjected to a reaction, coumarin molecules are connected onto a polyacid molecular system in a covalent bond manner through the reaction of the coumarin derivatives containing the acyl chloride groups at the tail ends and polyacid molecules containing the amino groups, three polyacid-coumarin composites with different polyacids are prepared, and photochromic behaviors of the composites in a solvent state and in a prepared film state are studied respectively. Results show that the composites have high sensitivity and stable color change performance.

Synthesis of some novel coumarin esters has been accomplished through iodine-catalyzed method using 4-methylumbelliferone as the starting material. Condensation of hydrazide, which was obtained in two steps from 4-methylumbelliferone, with some arylaldhydes provided hydrazone derivatives, while the reaction with phenylthioisocyanate leads to the thiosemicarbazide that evolved into two new compounds. Finally, condensation reaction of hydrazide with three diketones afforded new pyrrole and pyrazole derivatives. Structures of all synthesized compounds were established on the basis of spectroscopic methods including 1H NMR, 13C NMR and ES-HRMS. They were finally tested for their antimicrobial activity and the structure-activity relationship was discussed.

Considering the potential interest of heterocyclic compounds, the aim of the present study is to synthesize new coumarin derivatives, to provide their full chemical characterization and to evaluate their antimicrobial activities. The reaction of ethyl 2-(4-methyl-2-oxo-2H-chromen-7-yloxy) acetate 2 with sodium hydroxide afforded the corresponding 2-(2-oxo-4-methyl-2H-chromen-7-yloxy) acetic acid 3 which was esterified using a series of alcohols in the presence of iodine to yield a new series of coumarin esters 4a-j. On the other hand, treatment of the key intermediate 2 with an aqueous solution of hydrazine in ethanol at reflux gave the corresponding hydrazide 5 which further converted into coumarin derivatives 6a-f and 7a-c by condensation with a series of aromatic aldehydes and cyclic anhydrides, respectively. The synthesized compounds were completely characterized by 1H NMR, 13C NMR, IR and HRMS. The antibacterial and antifungal activities of the new synthesized compounds were evaluated using the disc diffusion method and seemed to be significant.

Bladder cancer is one of the most prevalent malignancies of the genitourinary tract, and approximately 25% of patients develop superficial cancers with invasive and metastatic pathology. Coumarins and their derivatives have antiproliferative activity and

Infectious diseases and the development of their resistance to antimicrobial agents are alarming issues worldwide and consistent efforts are being made to develop efficient antimicrobial agents. In this perspective, a series of novel ammonium and amide derivatives of pyranocoumarin and coumarin were synthesized and evaluated for their antimicrobial activity. Among them, six compounds exhibited significant activity against gram-positive bacteria Bacillus cereus (MTCC 430) and Bacillus subtilis (MTCC 121) and a gram-negative bacterium Pseudomonas aeruginosa (MTCC 741). The compound N,N,N-triethyl-10-(4,8,8-trimethyl-2-oxo-2,6,7,8-tetrahydropyrano[3,2-g]chromen-10-yloxy)decan-1-aminium bromide (16) exhibited the highest antibacterial activity with MIC value of 5 μg/ml in MDA. Compounds 17 and 18 exhibited modest antifungal activity with MIC of 6.25 μg/ml against Trichophyton rubrum (clinical isolate) in MDA. Haemolytic assay results demonstrated that three out of six compounds were safe at their respective MIC values. These results provide insights for further optimization of the scaffolds for designing the next generation of compounds as lead antimicrobial agents.

Using novel hybrid molecules for the treatment of tuberculosis is one of the latest approaches. Keeping this concept in mind, thirty two hybrid compounds were synthesized, with pyrrole as one of the moieties, clubbed to coumarin, ibuprofen and isoniazid. The compounds were evaluated against Mycobacterium tuberculosis H37Rv strain. Compounds 7e and 8e exhibited MIC of 3.7 and 5.10 μg mL-1 and growth inhibition of 95% and 92%, respectively. These compounds were also active against single drug resistant bacterial strains. The compounds were devoid of cytotoxicity when tested against Vero African green monkey kidney cell line. Docking study was carried out on enoyl acyl carrier protein enzyme to provide some understanding into the mechanism of action of these compounds.

Ethyl-2-(4-methyl-2-oxo-2-coumarin-7-yloxy)acetate 1 has been prepared from 7-hydroxy-4-methyl-2-coumarin, which on further treatment with hydrazine hydrate in boiling ethanol gave the hydrazide compound 2. The resulting hydrazide was reacted with substituted aryl isothiocyanates to form thiosemicarbazides compounds 3a, 3b, 3c, 3d, 3e. 1-(2-(4-Methyl-2-oxo-2- coumarin-7-yloxy)acetyl)-4-aryl thiosemicarbazides 3 underwent cyclization with different reagents under different reaction conditions to furnish coumarin derivatives possessing triazoles 4a, 4b, 4c, 4d, 4e, thiadiazoles 5a, 5b, 5c, 5d, 5e, and oxadiazoles 6a, 6b, 6c, 6d, 6e, respectively. The structures of all the compounds have been assigned by elemental analysis and spectral studies. The synthesized compounds were screened for their antimicrobial analgesic activities. The nonconventional controlled microwave irradiation synthesis is carried out at (200 W) at 70°C. This approach offers a number of advantages in terms of methodology, high-product yield, short reaction time, mild reaction conditions, environmentally benign, and easy workup.

Asthma is a chronic inflammatory disorder that causes contraction in the smooth muscle of the airway and blocking of airflow. Reversal the contractile process is a strategy for the search of new drugs that could be used for the treatment of asthma. This work reports the semisynthesis, ex vivo relaxing evaluation and SAR studies of a series of 18 coumarins. The results pointed that the ether derivatives 1-3, 7-9 and 13-15 showed the best activity (E max = 100%), where compound 2 (42 μM) was the most potent, being 4-times more active than theophylline (positive control). The ether homologation (methyl, ethyl and propyl) in position 7 or positions 6 and 7 of coumarins lead to relaxing effect, meanwhile formation of esters generated less active compounds than ethers. The SAR analysis showed that it is necessary the presence of two small ether groups and the methyl group at position 4 (site 3) encourage biological activity through soft hydrophobic changes in the molecule, without drastically affecting the cLogP.

According to literature data, thiosemicarbazide and thiazolidinone moieties should enhance biological properties of coumarin. Antioxidant, metal-chelating and antifungal activities of all compounds were investigated and compared to the activity of the sta

A series of new thiosubstituted 1,3,4-oxadiazole derivatives of coumarin were synthesised by reaction of 7-((5- mercapto-1,3,4-oxadiazol-2-yl)methoxy)-4- methyl-2H-chromen-2-one and α-haloketones by grinding, in solvent-free conditions at room temperature. The reaction was also carried out in ethanol in reflux conditions. Shorter reaction time and better yields were observed in solvent-free conditions. The structures of the compounds were characterised by IR, NMR, elemental analysis and mass spectral data. The synthesised compounds were evaluated for their in vitro antimicrobial screening on different strains of bacteria and fungi. Most of the compounds showed good to moderate activities.

A number of new [(4-methyl-2-oxo-2H-chromen- 7-yl)amino]methylcoumarins (5a-c), benzofuran (6), and benzoxazol (7) were synthesized through the reaction of 7-amino-4-methylcoumarin (1) with a number of organic halides. In addition, series of N-substituted 2-[(4-methyl-2-oxo-2H-chromen-7-yl)oxy]acetohydrazide (11a-h) and (12a-d) were prepared from the reaction of 2-[(4-methyl-2- oxo-2H-chromen-7-yl)oxy]acetohydrazide (8) with corresponding heteroaryl/alkyl halides (2-4, 9, and 10). The synthesized compounds were characterized by elemental analysis and by spectroscopic techniques such as 1H-NMR, 13C-NMR, and mass spectrometry and were tested for their in vitro antimicrobial activity. The newly synthesized compounds exerted significant inhibitory activity against the growth of tested bacterial strains and a few of them are found to be potent antimicrobial agents. Springer Science+Business Media, LLC 2011.

The synthesis of several phenacyl ester derivatives linked to oxygen and nitrogen heterocycles, benzoquinolone and (benzo)coumarins, was carried out in an effort to obtain systems that could be applied as photocleavable (bi)functional linkers for solid phase peptide synthesis. The heterocycles were attached to a spacer, with different lengths, followed by coupling to 2-bromo-1-phenylpropan-1-one, acting as a model for the solid support. Photolysis studies of the resulting phenacyl ester derivatives were carried out by irradiation in a photochemical reactor at different wavelengths (300, 350 and 419 nm), in methanol/HEPES buffer solution (80:20).

New coumarin derivatives namely (2-(4-methyl-2-oxo-2H-chromen-7-yloxy)- N-(4-oxo-2-phenylthiazolidin-3-yl)acetamide, N-(2-(3-methoxyphenyl)-4- oxothiazolidin- 3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamide, 2-(4-methyl-2-oxo-2H-chromen- 7-yloxy)-N-(

2-[(4-Methyl-2-oxo-2H-chromen-7-yl)oxy]acetohydrazide (3), aryl/hetero aromatic aldehydes were condensed under reflux temperature for the synthesis of new Schiff base 2-[(4-methyl-2-oxo-2H-chromen-7-yl)oxy]-N'- (substitutedmethylene)acetohydrazides (4a-l)

An efficient synthesis of different novel 2,5-dimethyl-N-substituted pyrrole derivatives by the Paal-Knorr condensation has been accomplished using uranyl nitrate hexahydrate as catalyst under soft conditions and ultrasonic irradiation. The synthesized compounds were confirmed through spectral characterization using IR, 1H NMR, 13C NMR and mass spectra.

A series of Schiff's bases (E)-N-2-aryliden-2-(4-methyl-2-oxo-2H-chromen-7- yloxy)acetohydrazides 2a-l and N-(2-(substituted phenyl)-4-oxo-thiazolidin-3- yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamides 3a-l were synthesized and evaluated for their ant

A series of some innovative 7-((4-substituted thiazol-2-yl) metiioxy)-4-memyl-2H-chromen-2-one (4a-d) & (6a-b) were syntiiesized starting from ethyl 2-(4-methyl-2-oxo-2H-chromone-7-yloxy)acetate (la). Reaction of compound (la) with aqueous ammonia yielded 2-(4-methyl-2-oxo-2H-chromomen-7- yloxy)acetamide (2a). Compound (2a) on reaction with P2S5 in dioxane gave 2-(4-methyl-2-oxo-2H-chromomen-7yloxy) ethanethioamide (3a). Reaction of (3a) with different substituted phenacylbromide/ dichloroacetone afforded (4a-d) & (5a). Condensation of (5a) with different secondary amines gave desired compounds (6a-b). The newly synthesized compounds are characterized by IR, 1H NMR and mass spectral studies. These synthesized compounds were also screened for their antibacterial and antifungal activities.

Coumarin derivatives were prepared by the von Pechmann reaction of PEG-bound acetoacetate reagent with phenols in the presence of TiCl4 in excellent yield and purity with a facile workup procedure. The polymer reagent could be recycled two to four times without diminishing the yield or purity. Copyright Taylor & Francis Group, LLC.

The ability of titanium(IV) chloride as a catalyst to promote the Pechmann condensation reaction with a range of phenols and β-keto esters is described.The reaction was carried out by addition of TiCl4 to a mixture of the phenol and the β-keto ester with thorough stirring in the absence of a solvent and represents an improvement on the classical Pechmann conditions. The yields of coumarins obtained via this novel protocol were significantly higher than those using the conventional method and the reaction duration was reduced to a few minutes or even a few seconds.

2-(Coumarin-3-yl)-5-aryl-1,3,4-oxadiazole derivatives 3-5 have been synthesised by condensing hydrazide 2 of 3-carbethoxycoumarin with various aromatic acids. Compound 3 is also synthesized by another route involving synthesis of an intermediate N-2-hydroxy benzylidene coumarin-3-carboxyhydrazide 6 which is prepared by reacting 2 with salicylaldehyde. On refluxing it in presence of chloramine T the desired 1,3,4- oxadiazole derivative 3 is obtained. In another set of experiments, 4-methyl-7-(5-phenyl-1,3,4-oxadiazole-2-yl methoxy) coumarin 10 and 4-methyl-7-(5-amino-1,3,4-oxadiazo-2-yl methoxy) coumarin 11 were prepared by condensing 4-methyl coumarinyl-7-oxyacetic hydrazide 9 with benzoic acid and cyanogen bromide respectively. All the oxadiazole derivatives and the compound 6 have been tested for their antiinflammatory, analgesic and antimicrobial activity with interesting results.

A series of 7-O-acetamidyl-4-alkyl-2H-1-benzopyran-2-ones (5-23) has been synthesized by amidation of 7-O-(carbethoxymethyl)-4-alkyl-2H-1-benzopyran-2- ones (2a, 2b) with different primary and secondary amines in fair to good yield. The resulting compound

4-Substituted coumarins were efficiently and rapidly synthesised via Pechmann condensation of phenols with ethyl acetoacetate catalyzed by P2O5/molecular sieves in satisfactory yields.

A new synthetic route to coumarinyloxyaldehydes starting from hydroxycoumarins is presented; these compounds, useful intermediates in the preparation of natural products such as geiparvarin and psoralens, are now available in excellent yields with a simple workup procedure. Moreover the reported route has been applied to dihydroxycoumarins.

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