ABSTRACT In the present study, a focused library of (Z)-acrylonitrile analogues (library A &a... more ABSTRACT In the present study, a focused library of (Z)-acrylonitrile analogues (library A & B) were synthesized, which were typically accessed via a facile Knoevenagel condensation between p-nitrophenylacetonitrile and appropriately substituted aromatic aldehydes (1a–i) and 3-formyl chromones (3a–c). This new synthetic eco-friendly approach resulted in a remarkable improvement in the synthetic efficiency (83–92% yield), high purity, minimizing the production of chemical wastes without using highly toxic reagents for the synthesis and, more notably, it improved the selectivity for (Z)-acrylonitrile derivatives. By performing DFT calculations, it was found that the (Z)-isomer of compound 2b is stabilized by 2.61 kcal mol−1 more than the (E)-isomer. All of the compounds were tested for acetylcholinesterase (AChE) inhibition. Compounds 2a and 4c, displayed the strongest inhibition, with IC50 values of 0.20 μM and 0.22 μM respectively. The methoxy group at the para-position of phenyl ring A was found to be essential for AChE inhibition.
In the present study, a library of hydrazone analogues 2(a–j) and 4(a–e) were synthesized, which ... more In the present study, a library of hydrazone analogues 2(a–j) and 4(a–e) were synthesized, which were typically accessed via a solvent-free facile nucleophilic addition between hydrazine hydrate and appropriately substituted aromatic aldehydes 1(a–j) and 3-formylchromones 3(a–e). The molecular structure of compound (2f) was well supported by single crystal X-ray crystallographic analysis and also verified by DFT calculations. This new synthetic, eco-friendly, sustainable protocol resulted in a remarkable improvement in the synthetic efficiency (90–98% yield), high purity, using [Et3NH][HSO4] as a catalyst and an environmentally benign solvent eliminating the need for a volatile organic solvent and additional catalyst. This ionic liquid is air and water stable and easy to prepare from cheap amine and acid. The present methodology is a green protocol offering several advantages such as, excellent yield of products, minimizing production of chemical wastes, shorter reaction profile, mild reaction conditions, simple operational procedure, easy preparation of catalyst and its recyclability up to five cycles without any appreciable loss in catalytic activity. The optimization conditions carried out in the present study revealed that 20 mol% of ionic liquid catalyst under solvent-free condition at 120 1C are the best conditions for the synthesis of hydrazone derivatives in excellent yields.
In the present study, a new series of ester
analogues of substituted coumarin-3-carboxylic acids ... more In the present study, a new series of ester analogues of substituted coumarin-3-carboxylic acids were synthesized which were typically accessed via a facile esterification reaction between propargyl alcohol and appropriately substituted coumarin-3-carboxylic acids (1–5). This new environmentally benign solid acid catalyst catalyzed, synthetic eco-friendly approach resulted in a noteworthy progress in synthetic efficiency (89–94 % yield), high purity, operational simplicity, mild reaction conditions, cleaner reaction profiles, recyclability of the catalyst and minimizing the production of chemical wastes without using highly toxic reagents for the synthesis. The molecular structure of compound 6 was authenticated by single crystal X-ray crystallographic analysis. The structure and morphology of the catalyst has been established on the basis of FT-IR, scanning electron microscopy–energy dispersion X-ray spectrometry and transmission electron microscopy. The promising bioactive score against enzymatic inhibition prompted us to carry out acetylcholinesterase inhibition screening of the synthesized compounds (6–10). A computer-aided molecular docking study was carried out to validate the specific binding mode of the newly synthesized compounds into the active site of receptor to bear out the specific binding modes of the compounds.
The title compound, C20H16O6, which contains one chiral
centre, crystallizes as a racemate. The m... more The title compound, C20H16O6, which contains one chiral centre, crystallizes as a racemate. The mean planes of the two coumarin units make a dihedral angle of 88.07 (2). The pyrone ring containing the chiral centre adopts a sofa conformation. In the crystal, four molecules are linked by O—H O hydrogen bonds, forming a tetrameric ring with graph-set motif R4 4(32). These tetramers are further linked by O—H O hydrogen bonds into a three-dimensional network
Petroleum ether–benzene extract of the leaves of Ficus krishnae afforded a novel halogenated 2Hch... more Petroleum ether–benzene extract of the leaves of Ficus krishnae afforded a novel halogenated 2Hchromen- 2-one named 3-chloro-7-methoxy-4-methyl-chromen-2-one. Its structure was established on basis of chemical and physical evidence (IR, 1H NMR, and MS data) as well as on X-ray crystallographic studies.
Two new compounds 2 and 4, along with two known compounds 1 and 3, were isolated
for the first ti... more Two new compounds 2 and 4, along with two known compounds 1 and 3, were isolated for the first time from 95% ethanolic extract of the leaves of Ficus rumphii. Their structures were elucidated on the basis of chemical and physical evidences (elemental analysis, UV, IR, 1H NMR, 13C NMR and mass spectra) and comparison with the literature compounds. Structural authentication of compound 4 was further validated by single-crystal X-ray analysis and DFT calculations. The compounds 1–4 were screened for in vitro cytotoxicity against cancer and non-cancer cells and also tested for genotoxicity (comet assay). Compounds 2 and 4 displayed significant activity against HL-60 with IC50 values of 3.3 and 2.3mM, respectively. The results revealed that compound 4 has better prospectus to act as cancer chemotherapeutic candidate which warrants further in vivo anticancer investigations.
A series of 4-arylidene-2-phenyl-5(4H)-azlactones have been synthesized, characterized on the bas... more A series of 4-arylidene-2-phenyl-5(4H)-azlactones have been synthesized, characterized on the basis of systematic spectral studies and screened for their biological activity. Moreover, the Z-configuration and stability of compounds was ascertained on the basis of spectroscopy techniques, X-ray studies as well as DFT calculations.
A series of tetrazinan-3-thione and 3-oxo-pyrazolidine-4-carbonitrile derivatives of steroids(1―3... more A series of tetrazinan-3-thione and 3-oxo-pyrazolidine-4-carbonitrile derivatives of steroids(1―3) were synthesized with silica-chloride as a heterogeneous catalyst. The synthesized compounds 4―9 were obtained in substantial yields. In vitro evaluation of anticancer and antioxidant activity of the synthesized compounds was carried out via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and 1,1-diphenyl-2-picrylhydrazyl(DPPH) assays, respectively. Compound 6 exhibited promising anti-proliferative activity towards a panel of cancer cell lines. The significant activity of compound 6 was further ascertained on structural, molecular modelling and docking studies. This study may provide a valuable insight into the further design and development of more potent biologically active compounds.
A series of new substituted 3-formyl chromone derivatives (4–6) were synthesized by one step reac... more A series of new substituted 3-formyl chromone derivatives (4–6) were synthesized by one step reaction methodology by knoevenagel condensation, structurally similar to known bisintercalators. The new compounds were characterized by IR, 1H NMR, 13C NMR, MS and analytical data. The in vitro DNA binding profile of compounds (4–6) was carried out by absorption, fluorescence and viscosity measurements. It was found that synthesized compounds, especially compound 6 (evident from binding constant value) bind strongly with calf thymus DNA, presumably via an intercalation mode. Additionally, molecular docking studies of compounds (4–6) were carried out with B–DNA (PDBID: 1BNA) which revealed that partial intercalative mode of mechanism is operational in synthesized compounds (4–6) with CT-DNA. The binding constants evaluated from fluorescence spectroscopy of compounds with CT-DNA follows the order compound 6 > compound 5 > compound 4. All the compounds (4–6) were screened for acetylcholinesterase inhibition assay. It can be inferred from data, that compound (6) showed potent AChE inhibition having IC50 = 0.27 lM, almost in vicinity to reference drug Tacrine (IC50 = 0.19 lM).
In the present study, a focused library of (Z)-acrylonitrile analogues (library A & B) were synth... more In the present study, a focused library of (Z)-acrylonitrile analogues (library A & B) were synthesized, which were typically accessed via a facile Knoevenagel condensation between p-nitrophenylacetonitrile and appropriately substituted aromatic aldehydes (1a–i) and 3-formyl chromones (3a–c). This new synthetic eco-friendly approach resulted in a remarkable improvement in the synthetic efficiency (83–92% yield), high purity, minimizing the production of chemical wastes without using highly toxic reagents for the synthesis and, more notably, it improved the selectivity for (Z)-acrylonitrile derivatives. By performing DFT calculations, it was found that the (Z)-isomer of compound 2b is stabilized by 2.61 kcal mol1 more than the (E)-isomer. All of the compounds were tested for acetylcholinesterase (AChE) inhibition. Compounds 2a and 4c, displayed the strongest inhibition, with IC50 values of 0.20 mM and 0.22 mM respectively. The methoxy group at the para-position of phenyl ring A was found to be essential for AChE inhibition.
ABSTRACT In the present study, a focused library of (Z)-acrylonitrile analogues (library A &a... more ABSTRACT In the present study, a focused library of (Z)-acrylonitrile analogues (library A & B) were synthesized, which were typically accessed via a facile Knoevenagel condensation between p-nitrophenylacetonitrile and appropriately substituted aromatic aldehydes (1a–i) and 3-formyl chromones (3a–c). This new synthetic eco-friendly approach resulted in a remarkable improvement in the synthetic efficiency (83–92% yield), high purity, minimizing the production of chemical wastes without using highly toxic reagents for the synthesis and, more notably, it improved the selectivity for (Z)-acrylonitrile derivatives. By performing DFT calculations, it was found that the (Z)-isomer of compound 2b is stabilized by 2.61 kcal mol−1 more than the (E)-isomer. All of the compounds were tested for acetylcholinesterase (AChE) inhibition. Compounds 2a and 4c, displayed the strongest inhibition, with IC50 values of 0.20 μM and 0.22 μM respectively. The methoxy group at the para-position of phenyl ring A was found to be essential for AChE inhibition.
In the present study, a library of hydrazone analogues 2(a–j) and 4(a–e) were synthesized, which ... more In the present study, a library of hydrazone analogues 2(a–j) and 4(a–e) were synthesized, which were typically accessed via a solvent-free facile nucleophilic addition between hydrazine hydrate and appropriately substituted aromatic aldehydes 1(a–j) and 3-formylchromones 3(a–e). The molecular structure of compound (2f) was well supported by single crystal X-ray crystallographic analysis and also verified by DFT calculations. This new synthetic, eco-friendly, sustainable protocol resulted in a remarkable improvement in the synthetic efficiency (90–98% yield), high purity, using [Et3NH][HSO4] as a catalyst and an environmentally benign solvent eliminating the need for a volatile organic solvent and additional catalyst. This ionic liquid is air and water stable and easy to prepare from cheap amine and acid. The present methodology is a green protocol offering several advantages such as, excellent yield of products, minimizing production of chemical wastes, shorter reaction profile, mild reaction conditions, simple operational procedure, easy preparation of catalyst and its recyclability up to five cycles without any appreciable loss in catalytic activity. The optimization conditions carried out in the present study revealed that 20 mol% of ionic liquid catalyst under solvent-free condition at 120 1C are the best conditions for the synthesis of hydrazone derivatives in excellent yields.
In the present study, a new series of ester
analogues of substituted coumarin-3-carboxylic acids ... more In the present study, a new series of ester analogues of substituted coumarin-3-carboxylic acids were synthesized which were typically accessed via a facile esterification reaction between propargyl alcohol and appropriately substituted coumarin-3-carboxylic acids (1–5). This new environmentally benign solid acid catalyst catalyzed, synthetic eco-friendly approach resulted in a noteworthy progress in synthetic efficiency (89–94 % yield), high purity, operational simplicity, mild reaction conditions, cleaner reaction profiles, recyclability of the catalyst and minimizing the production of chemical wastes without using highly toxic reagents for the synthesis. The molecular structure of compound 6 was authenticated by single crystal X-ray crystallographic analysis. The structure and morphology of the catalyst has been established on the basis of FT-IR, scanning electron microscopy–energy dispersion X-ray spectrometry and transmission electron microscopy. The promising bioactive score against enzymatic inhibition prompted us to carry out acetylcholinesterase inhibition screening of the synthesized compounds (6–10). A computer-aided molecular docking study was carried out to validate the specific binding mode of the newly synthesized compounds into the active site of receptor to bear out the specific binding modes of the compounds.
The title compound, C20H16O6, which contains one chiral
centre, crystallizes as a racemate. The m... more The title compound, C20H16O6, which contains one chiral centre, crystallizes as a racemate. The mean planes of the two coumarin units make a dihedral angle of 88.07 (2). The pyrone ring containing the chiral centre adopts a sofa conformation. In the crystal, four molecules are linked by O—H O hydrogen bonds, forming a tetrameric ring with graph-set motif R4 4(32). These tetramers are further linked by O—H O hydrogen bonds into a three-dimensional network
Petroleum ether–benzene extract of the leaves of Ficus krishnae afforded a novel halogenated 2Hch... more Petroleum ether–benzene extract of the leaves of Ficus krishnae afforded a novel halogenated 2Hchromen- 2-one named 3-chloro-7-methoxy-4-methyl-chromen-2-one. Its structure was established on basis of chemical and physical evidence (IR, 1H NMR, and MS data) as well as on X-ray crystallographic studies.
Two new compounds 2 and 4, along with two known compounds 1 and 3, were isolated
for the first ti... more Two new compounds 2 and 4, along with two known compounds 1 and 3, were isolated for the first time from 95% ethanolic extract of the leaves of Ficus rumphii. Their structures were elucidated on the basis of chemical and physical evidences (elemental analysis, UV, IR, 1H NMR, 13C NMR and mass spectra) and comparison with the literature compounds. Structural authentication of compound 4 was further validated by single-crystal X-ray analysis and DFT calculations. The compounds 1–4 were screened for in vitro cytotoxicity against cancer and non-cancer cells and also tested for genotoxicity (comet assay). Compounds 2 and 4 displayed significant activity against HL-60 with IC50 values of 3.3 and 2.3mM, respectively. The results revealed that compound 4 has better prospectus to act as cancer chemotherapeutic candidate which warrants further in vivo anticancer investigations.
A series of 4-arylidene-2-phenyl-5(4H)-azlactones have been synthesized, characterized on the bas... more A series of 4-arylidene-2-phenyl-5(4H)-azlactones have been synthesized, characterized on the basis of systematic spectral studies and screened for their biological activity. Moreover, the Z-configuration and stability of compounds was ascertained on the basis of spectroscopy techniques, X-ray studies as well as DFT calculations.
A series of tetrazinan-3-thione and 3-oxo-pyrazolidine-4-carbonitrile derivatives of steroids(1―3... more A series of tetrazinan-3-thione and 3-oxo-pyrazolidine-4-carbonitrile derivatives of steroids(1―3) were synthesized with silica-chloride as a heterogeneous catalyst. The synthesized compounds 4―9 were obtained in substantial yields. In vitro evaluation of anticancer and antioxidant activity of the synthesized compounds was carried out via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and 1,1-diphenyl-2-picrylhydrazyl(DPPH) assays, respectively. Compound 6 exhibited promising anti-proliferative activity towards a panel of cancer cell lines. The significant activity of compound 6 was further ascertained on structural, molecular modelling and docking studies. This study may provide a valuable insight into the further design and development of more potent biologically active compounds.
A series of new substituted 3-formyl chromone derivatives (4–6) were synthesized by one step reac... more A series of new substituted 3-formyl chromone derivatives (4–6) were synthesized by one step reaction methodology by knoevenagel condensation, structurally similar to known bisintercalators. The new compounds were characterized by IR, 1H NMR, 13C NMR, MS and analytical data. The in vitro DNA binding profile of compounds (4–6) was carried out by absorption, fluorescence and viscosity measurements. It was found that synthesized compounds, especially compound 6 (evident from binding constant value) bind strongly with calf thymus DNA, presumably via an intercalation mode. Additionally, molecular docking studies of compounds (4–6) were carried out with B–DNA (PDBID: 1BNA) which revealed that partial intercalative mode of mechanism is operational in synthesized compounds (4–6) with CT-DNA. The binding constants evaluated from fluorescence spectroscopy of compounds with CT-DNA follows the order compound 6 > compound 5 > compound 4. All the compounds (4–6) were screened for acetylcholinesterase inhibition assay. It can be inferred from data, that compound (6) showed potent AChE inhibition having IC50 = 0.27 lM, almost in vicinity to reference drug Tacrine (IC50 = 0.19 lM).
In the present study, a focused library of (Z)-acrylonitrile analogues (library A & B) were synth... more In the present study, a focused library of (Z)-acrylonitrile analogues (library A & B) were synthesized, which were typically accessed via a facile Knoevenagel condensation between p-nitrophenylacetonitrile and appropriately substituted aromatic aldehydes (1a–i) and 3-formyl chromones (3a–c). This new synthetic eco-friendly approach resulted in a remarkable improvement in the synthetic efficiency (83–92% yield), high purity, minimizing the production of chemical wastes without using highly toxic reagents for the synthesis and, more notably, it improved the selectivity for (Z)-acrylonitrile derivatives. By performing DFT calculations, it was found that the (Z)-isomer of compound 2b is stabilized by 2.61 kcal mol1 more than the (E)-isomer. All of the compounds were tested for acetylcholinesterase (AChE) inhibition. Compounds 2a and 4c, displayed the strongest inhibition, with IC50 values of 0.20 mM and 0.22 mM respectively. The methoxy group at the para-position of phenyl ring A was found to be essential for AChE inhibition.
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typically accessed via a solvent-free facile nucleophilic addition between hydrazine hydrate and
appropriately substituted aromatic aldehydes 1(a–j) and 3-formylchromones 3(a–e). The molecular
structure of compound (2f) was well supported by single crystal X-ray crystallographic analysis and also
verified by DFT calculations. This new synthetic, eco-friendly, sustainable protocol resulted in a remarkable
improvement in the synthetic efficiency (90–98% yield), high purity, using [Et3NH][HSO4] as a catalyst
and an environmentally benign solvent eliminating the need for a volatile organic solvent and additional
catalyst. This ionic liquid is air and water stable and easy to prepare from cheap amine and acid. The present
methodology is a green protocol offering several advantages such as, excellent yield of products,
minimizing production of chemical wastes, shorter reaction profile, mild reaction conditions, simple operational
procedure, easy preparation of catalyst and its recyclability up to five cycles without any appreciable
loss in catalytic activity. The optimization conditions carried out in the present study revealed that
20 mol% of ionic liquid catalyst under solvent-free condition at 120 1C are the best conditions for the
synthesis of hydrazone derivatives in excellent yields.
analogues of substituted coumarin-3-carboxylic acids were
synthesized which were typically accessed via a facile
esterification reaction between propargyl alcohol and
appropriately substituted coumarin-3-carboxylic acids
(1–5). This new environmentally benign solid acid catalyst
catalyzed, synthetic eco-friendly approach resulted in a
noteworthy progress in synthetic efficiency (89–94 %
yield), high purity, operational simplicity, mild reaction
conditions, cleaner reaction profiles, recyclability of the
catalyst and minimizing the production of chemical wastes
without using highly toxic reagents for the synthesis. The
molecular structure of compound 6 was authenticated by
single crystal X-ray crystallographic analysis. The structure
and morphology of the catalyst has been established on the
basis of FT-IR, scanning electron microscopy–energy dispersion
X-ray spectrometry and transmission electron
microscopy. The promising bioactive score against enzymatic
inhibition prompted us to carry out acetylcholinesterase
inhibition screening of the synthesized compounds
(6–10). A computer-aided molecular docking study was
carried out to validate the specific binding mode of the
newly synthesized compounds into the active site of receptor to bear out the specific binding modes of the
compounds.
centre, crystallizes as a racemate. The mean planes of the two
coumarin units make a dihedral angle of 88.07 (2). The
pyrone ring containing the chiral centre adopts a sofa
conformation. In the crystal, four molecules are linked by
O—H O hydrogen bonds, forming a tetrameric ring with
graph-set motif R4
4(32). These tetramers are further linked by
O—H O hydrogen bonds into a three-dimensional network
2-one named 3-chloro-7-methoxy-4-methyl-chromen-2-one. Its structure was established
on basis of chemical and physical evidence (IR, 1H NMR, and MS data) as well as on X-ray
crystallographic studies.
for the first time from 95% ethanolic extract of the leaves of Ficus rumphii. Their
structures were elucidated on the basis of chemical and physical evidences (elemental
analysis, UV, IR, 1H NMR, 13C NMR and mass spectra) and comparison with the
literature compounds. Structural authentication of compound 4 was further validated
by single-crystal X-ray analysis and DFT calculations. The compounds 1–4 were
screened for in vitro cytotoxicity against cancer and non-cancer cells and also tested for
genotoxicity (comet assay). Compounds 2 and 4 displayed significant activity against
HL-60 with IC50 values of 3.3 and 2.3mM, respectively. The results revealed that
compound 4 has better prospectus to act as cancer chemotherapeutic candidate which
warrants further in vivo anticancer investigations.
systematic spectral studies and screened for their biological activity. Moreover, the Z-configuration
and stability of compounds was ascertained on the basis of spectroscopy techniques, X-ray studies as well
as DFT calculations.
synthesized with silica-chloride as a heterogeneous catalyst. The synthesized compounds 4―9 were obtained in substantial
yields. In vitro evaluation of anticancer and antioxidant activity of the synthesized compounds was carried out
via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and 1,1-diphenyl-2-picrylhydrazyl(DPPH)
assays, respectively. Compound 6 exhibited promising anti-proliferative activity towards a panel of cancer cell lines.
The significant activity of compound 6 was further ascertained on structural, molecular modelling and docking studies.
This study may provide a valuable insight into the further design and development of more potent biologically
active compounds.
methodology by knoevenagel condensation, structurally similar to known bisintercalators. The new compounds
were characterized by IR, 1H NMR, 13C NMR, MS and analytical data. The in vitro DNA binding
profile of compounds (4–6) was carried out by absorption, fluorescence and viscosity measurements. It
was found that synthesized compounds, especially compound 6 (evident from binding constant value)
bind strongly with calf thymus DNA, presumably via an intercalation mode. Additionally, molecular docking
studies of compounds (4–6) were carried out with B–DNA (PDBID: 1BNA) which revealed that partial
intercalative mode of mechanism is operational in synthesized compounds (4–6) with CT-DNA. The binding
constants evaluated from fluorescence spectroscopy of compounds with CT-DNA follows the order
compound 6 > compound 5 > compound 4. All the compounds (4–6) were screened for acetylcholinesterase
inhibition assay. It can be inferred from data, that compound (6) showed potent AChE inhibition having
IC50 = 0.27 lM, almost in vicinity to reference drug Tacrine (IC50 = 0.19 lM).
which were typically accessed via a facile Knoevenagel condensation between p-nitrophenylacetonitrile
and appropriately substituted aromatic aldehydes (1a–i) and 3-formyl chromones (3a–c). This new synthetic
eco-friendly approach resulted in a remarkable improvement in the synthetic efficiency (83–92% yield), high
purity, minimizing the production of chemical wastes without using highly toxic reagents for the synthesis
and, more notably, it improved the selectivity for (Z)-acrylonitrile derivatives. By performing DFT calculations,
it was found that the (Z)-isomer of compound 2b is stabilized by 2.61 kcal mol1 more than the (E)-isomer.
All of the compounds were tested for acetylcholinesterase (AChE) inhibition. Compounds 2a and 4c,
displayed the strongest inhibition, with IC50 values of 0.20 mM and 0.22 mM respectively. The methoxy
group at the para-position of phenyl ring A was found to be essential for AChE inhibition.
typically accessed via a solvent-free facile nucleophilic addition between hydrazine hydrate and
appropriately substituted aromatic aldehydes 1(a–j) and 3-formylchromones 3(a–e). The molecular
structure of compound (2f) was well supported by single crystal X-ray crystallographic analysis and also
verified by DFT calculations. This new synthetic, eco-friendly, sustainable protocol resulted in a remarkable
improvement in the synthetic efficiency (90–98% yield), high purity, using [Et3NH][HSO4] as a catalyst
and an environmentally benign solvent eliminating the need for a volatile organic solvent and additional
catalyst. This ionic liquid is air and water stable and easy to prepare from cheap amine and acid. The present
methodology is a green protocol offering several advantages such as, excellent yield of products,
minimizing production of chemical wastes, shorter reaction profile, mild reaction conditions, simple operational
procedure, easy preparation of catalyst and its recyclability up to five cycles without any appreciable
loss in catalytic activity. The optimization conditions carried out in the present study revealed that
20 mol% of ionic liquid catalyst under solvent-free condition at 120 1C are the best conditions for the
synthesis of hydrazone derivatives in excellent yields.
analogues of substituted coumarin-3-carboxylic acids were
synthesized which were typically accessed via a facile
esterification reaction between propargyl alcohol and
appropriately substituted coumarin-3-carboxylic acids
(1–5). This new environmentally benign solid acid catalyst
catalyzed, synthetic eco-friendly approach resulted in a
noteworthy progress in synthetic efficiency (89–94 %
yield), high purity, operational simplicity, mild reaction
conditions, cleaner reaction profiles, recyclability of the
catalyst and minimizing the production of chemical wastes
without using highly toxic reagents for the synthesis. The
molecular structure of compound 6 was authenticated by
single crystal X-ray crystallographic analysis. The structure
and morphology of the catalyst has been established on the
basis of FT-IR, scanning electron microscopy–energy dispersion
X-ray spectrometry and transmission electron
microscopy. The promising bioactive score against enzymatic
inhibition prompted us to carry out acetylcholinesterase
inhibition screening of the synthesized compounds
(6–10). A computer-aided molecular docking study was
carried out to validate the specific binding mode of the
newly synthesized compounds into the active site of receptor to bear out the specific binding modes of the
compounds.
centre, crystallizes as a racemate. The mean planes of the two
coumarin units make a dihedral angle of 88.07 (2). The
pyrone ring containing the chiral centre adopts a sofa
conformation. In the crystal, four molecules are linked by
O—H O hydrogen bonds, forming a tetrameric ring with
graph-set motif R4
4(32). These tetramers are further linked by
O—H O hydrogen bonds into a three-dimensional network
2-one named 3-chloro-7-methoxy-4-methyl-chromen-2-one. Its structure was established
on basis of chemical and physical evidence (IR, 1H NMR, and MS data) as well as on X-ray
crystallographic studies.
for the first time from 95% ethanolic extract of the leaves of Ficus rumphii. Their
structures were elucidated on the basis of chemical and physical evidences (elemental
analysis, UV, IR, 1H NMR, 13C NMR and mass spectra) and comparison with the
literature compounds. Structural authentication of compound 4 was further validated
by single-crystal X-ray analysis and DFT calculations. The compounds 1–4 were
screened for in vitro cytotoxicity against cancer and non-cancer cells and also tested for
genotoxicity (comet assay). Compounds 2 and 4 displayed significant activity against
HL-60 with IC50 values of 3.3 and 2.3mM, respectively. The results revealed that
compound 4 has better prospectus to act as cancer chemotherapeutic candidate which
warrants further in vivo anticancer investigations.
systematic spectral studies and screened for their biological activity. Moreover, the Z-configuration
and stability of compounds was ascertained on the basis of spectroscopy techniques, X-ray studies as well
as DFT calculations.
synthesized with silica-chloride as a heterogeneous catalyst. The synthesized compounds 4―9 were obtained in substantial
yields. In vitro evaluation of anticancer and antioxidant activity of the synthesized compounds was carried out
via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and 1,1-diphenyl-2-picrylhydrazyl(DPPH)
assays, respectively. Compound 6 exhibited promising anti-proliferative activity towards a panel of cancer cell lines.
The significant activity of compound 6 was further ascertained on structural, molecular modelling and docking studies.
This study may provide a valuable insight into the further design and development of more potent biologically
active compounds.
methodology by knoevenagel condensation, structurally similar to known bisintercalators. The new compounds
were characterized by IR, 1H NMR, 13C NMR, MS and analytical data. The in vitro DNA binding
profile of compounds (4–6) was carried out by absorption, fluorescence and viscosity measurements. It
was found that synthesized compounds, especially compound 6 (evident from binding constant value)
bind strongly with calf thymus DNA, presumably via an intercalation mode. Additionally, molecular docking
studies of compounds (4–6) were carried out with B–DNA (PDBID: 1BNA) which revealed that partial
intercalative mode of mechanism is operational in synthesized compounds (4–6) with CT-DNA. The binding
constants evaluated from fluorescence spectroscopy of compounds with CT-DNA follows the order
compound 6 > compound 5 > compound 4. All the compounds (4–6) were screened for acetylcholinesterase
inhibition assay. It can be inferred from data, that compound (6) showed potent AChE inhibition having
IC50 = 0.27 lM, almost in vicinity to reference drug Tacrine (IC50 = 0.19 lM).
which were typically accessed via a facile Knoevenagel condensation between p-nitrophenylacetonitrile
and appropriately substituted aromatic aldehydes (1a–i) and 3-formyl chromones (3a–c). This new synthetic
eco-friendly approach resulted in a remarkable improvement in the synthetic efficiency (83–92% yield), high
purity, minimizing the production of chemical wastes without using highly toxic reagents for the synthesis
and, more notably, it improved the selectivity for (Z)-acrylonitrile derivatives. By performing DFT calculations,
it was found that the (Z)-isomer of compound 2b is stabilized by 2.61 kcal mol1 more than the (E)-isomer.
All of the compounds were tested for acetylcholinesterase (AChE) inhibition. Compounds 2a and 4c,
displayed the strongest inhibition, with IC50 values of 0.20 mM and 0.22 mM respectively. The methoxy
group at the para-position of phenyl ring A was found to be essential for AChE inhibition.