Copper supported over silica exhibited very high activity and selectivity for the direct synthesis of indole at atmospheric pressure. Under the reaction temperature of 325C,the yield of indole could obtain 88%.
A new coordination polymer {[Cd（C_（21）H_（14）N_6）（C_8H_4O_4）]·H_2O}_n（1） was synthesized by an elaborate design via the reaction of 3-（2,6-di（pyrazin-2-yl）pyridin-4-yl）-1H-indole（bppi）,1,4-benzene-...A new coordination polymer {[Cd（C_（21）H_（14）N_6）（C_8H_4O_4）]·H_2O}_n（1） was synthesized by an elaborate design via the reaction of 3-（2,6-di（pyrazin-2-yl）pyridin-4-yl）-1H-indole（bppi）,1,4-benzene-dicarboxylic acid（H2bdc） and cadmium（Ⅱ） nitrate in CH_3OH/H_2O mixed solvents. Complex 1 crystallizes in orthorhombic,space group Ccca with a = 20.012（4）,b = 31.881（6）,c = 19.808（4） ？,V = 12638（4） ？~3,Z = 16,C_（29）H_（20）CdN_6O_5,M_r = 644.91,D_c = 1.356 g·cm^（-3）,μ = 0.735 mm^（-1）,F（000） = 5184,GOOF = 1.046,the final R = 0.0405 and wR = 0.1063 for 6870 observed reflections（I 〉 2σ（I））. The Cd（Ⅱ） centre is hepta-coordinated by three N and four O atoms from one bppi terminal ligand and two bdc2– ligands,respectively,displaying a capped trigonal prism geometry. Structure extension gives coordination polymeric chains,in which the bdc2– linkers connect Cd（Ⅱ） cations into a one-dimensional（1D） coordination polymer along the c axis,giving zigzag chains with the Cd···Cd separation of 11.178（1） ？. The adjacent bppi terminal ligands in the chains are anti-periplanar conformation. The three-dimensional（3D） structure is stabilized by π···π stacking and hydrogen-bonding interactions to form a supramolecular self-penetrating network with 1D channels. In 1,there are voids 2999.7 ？~3 with 23.7% of per unit cell volume. Thermal analysis indicates that the framework of 1 is stable until 651 K and the photoluminescence of 1 in the solid shows very weak fluorescence at 382 and 560 nm upon excitation at 310 nm.展开更多
Some new asymmetric thioethers 5 and 4-thiazolidinones 6 have been obtained from condensation of 5-formyl-3-(pyridin-4'-yl)-1,2,4-triazino[5,6-b] indole (3) with halogenated aromatic amines followed by addition of...Some new asymmetric thioethers 5 and 4-thiazolidinones 6 have been obtained from condensation of 5-formyl-3-(pyridin-4'-yl)-1,2,4-triazino[5,6-b] indole (3) with halogenated aromatic amines followed by addition of thiophenol and/or cycloaddition with thiolactic acids in nonpolar solvents. Structures of the products confirmed by elemental analysis and spectral measurements. The new systems obtained were evaluated as antifungal agents.展开更多
A novel series of ethyl 5-hydroxy-4-substituted aminomethyl-2-sulfinylmethyl-lH-indole-3-carboxylates 8a--8j and 11e--11f was synthesized and evaluated in HepG2.2.15 cells for their anti-hepatitits B virus（HBV） acti...A novel series of ethyl 5-hydroxy-4-substituted aminomethyl-2-sulfinylmethyl-lH-indole-3-carboxylates 8a--8j and 11e--11f was synthesized and evaluated in HepG2.2.15 cells for their anti-hepatitits B virus（HBV） activity and cytotoxicity. Among them, six compounds showed more potent inhibitory activity than lamivudine. Compound 8e exhibited the most significant anti-HBV activity with an IC50 value of 1.62 μmol/L, which was 33-times more potent than the reference drug lamivudine（IC50=54.78μmol/L）.展开更多
Two new indole alkaloids, named ibogamine-18-carboxylic acid, 3, 4-didehydro-7, 8-dioxo-methyl ester 1, ibogamine-18-carboxylic acid, 16, 17-didehydro-9, 17-dihydro-9-hydroxy （2-oxopropyl）-methyl ester 2, were isola...Two new indole alkaloids, named ibogamine-18-carboxylic acid, 3, 4-didehydro-7, 8-dioxo-methyl ester 1, ibogamine-18-carboxylic acid, 16, 17-didehydro-9, 17-dihydro-9-hydroxy （2-oxopropyl）-methyl ester 2, were isolated from Ervatamia hainanensis. Their structures were elucidated on the basis of spectroscopic methods.展开更多
An efficient synthesis of symmetrical 2,2-bis（1H-indol-3-yl）-2H-acenaphthen-1-one is achieved via a reaction of acenaphthe-nequinone and indoles catalyzed by solid superacid SO4^2-/TiO2 under solvent-free conditions...An efficient synthesis of symmetrical 2,2-bis（1H-indol-3-yl）-2H-acenaphthen-1-one is achieved via a reaction of acenaphthe-nequinone and indoles catalyzed by solid superacid SO4^2-/TiO2 under solvent-free conditions at room temperature by grinding, which provides an efficient route to the synthesis of symmetrical 2,2-bis（1H-indol-3-yl）-2H-acenaphthen-1-one.This procedure offers several advantages including solvent-free conditions,excellent yields of products,simple work-up as well as reuse of catalysts which makes it a useful and attractive protocol for the synthesis of these compounds.展开更多
A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracem...A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate （R）-methyl 2-chloropropionate with high enantiomeric excess （〉99%） after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration （80 mmol/L） of esterase EstC10 was higher than the kinetic resolution of another esterase, Estl2-7 （50 mmoFL）. The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of （R）-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.展开更多
Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis（2-methyl imidazole） ligands, namely, {[Cd2（tdc）2（bip）2]·7H20}n （1） and [Cd（tdc）（bib）]n （2） （Hgtdc = 3,4-thiophenedi...Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis（2-methyl imidazole） ligands, namely, {[Cd2（tdc）2（bip）2]·7H20}n （1） and [Cd（tdc）（bib）]n （2） （Hgtdc = 3,4-thiophenedicarboxylic acid, bip = 1,3-bis-（imidazol-2-methyl）propane and bib = 1,4-bis（imidazol-2-methyl）butane）, have been synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analyses reveal that 1 exhibits a two-dimensional （2D） layered network with 3-connected （6,3） topology, which is further connected into a three- dimensional （3D） supramolecular structure by intermolecular hydrogen bonds. However, 2 features a 2D network which can be rationalized as a 4-connected sql net. The results indicate the subtle difference of auxiliary bis（imidazol-2-methyl） ligands may lead to diverse architectures. Moreover, they exhibit luminescence emission in the solid state at room temperature.展开更多
A new halogenated biindole and a new apo-carotenone have been isolated from the ethanolic extract of the green alga Chaetomorpha basiretorsa Sethcell. On the basis of chemical and spectroscopic methods including 2D NM...A new halogenated biindole and a new apo-carotenone have been isolated from the ethanolic extract of the green alga Chaetomorpha basiretorsa Sethcell. On the basis of chemical and spectroscopic methods including 2D NMR technique, their structures have been elucidated as 4,4′-dichloro-5,5′-dibromo-7,7′-dimethoxy-2,2′-bi-1H-indole and 1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′- trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien-2-one, respectively.展开更多
The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, I...The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, IR, H RMS(ESI) and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group I2/c with a = 15.0212(10), b = 9.4911(6), c = 20.3075(13) A, β = 100.776(7)o, V = 2844.1(3)A3, Z = 8, Dc = 1.314 g/cm3, F(000) = 1184.0, μ = 0.089 mm-1, the final R = 0.0574 and w R = 0.1688 for 1701 observed reflections(I 】 2σ(I)). X-ray analysis indicates three major N(2)–H(2)···O(2), C(13)–H(13)···O(2), N(2)–H(2)···N(3) hydrogen bonds and π-π stacking interactions in the crystal structure. The preliminary biological test shows that the title compound has a good antitumor activity against A549 in vitro with the IC50 value of 35 μmol/L.展开更多
The coupling reaction of 3-cyanoacetyl-2-methylindole 1a with the aromatic diazonium salts gave the corresponding arylhydrazones 2a-e. Compounds 2 were used for synthesis of 4-aminopyrazole-5-carbonitrile 4a-e and 5-a...The coupling reaction of 3-cyanoacetyl-2-methylindole 1a with the aromatic diazonium salts gave the corresponding arylhydrazones 2a-e. Compounds 2 were used for synthesis of 4-aminopyrazole-5-carbonitrile 4a-e and 5-amino-4-arylazo-3-pyrazoles 5a-e derivatives. Also, treatment of 3-cyanoacetyl-2-phenylindole 1b with phenyl isothiocyanate gave the corresponding thioacetanilide 7. The later compound 7 was utilized as the key intermediate for the synthesis of some new thiadiazole derivatives 9a-r. The structures of all new compounds were elucidated on the basis of elemental analysis and spectral data.展开更多
The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, ...The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the GGA/PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Two possible reaction pathways were investigated in this study. The result indicates that the reaction Re→TS1→IM1→TSA2→IMA2→TSA3→IMA3→TSA4→IMA4→TSA5→P2 is the main pathway, the activation energy of which is the lowest. Re→TS1→IM1 is the rate-limiting step, with the activation energy being 221.54 kJ·mol^(-1) and the reaction heat being 10.06 kJ·mol^(-1). The dominant product predicted theoretically is in agreement with the experiment results.展开更多
It was successfully synthesized liquid crystal monomer acrylate that conjugated with two mesogens were cholesterol and p-hydroxyphenyl-2-methyl Butanoat which called MA （monomer cholesteryl acrylate） and monomer （S...It was successfully synthesized liquid crystal monomer acrylate that conjugated with two mesogens were cholesterol and p-hydroxyphenyl-2-methyl Butanoat which called MA （monomer cholesteryl acrylate） and monomer （S）-（＋）-4-（2-Methyl butanoat-l-butyloxy） phenyl 4-[1-（propenoyloxy） butyloxy] benzoate （MB）. Two monomers were characterized by DSC （differential scanning calorimetry）, POM （polarization optical microscopy） and XRD （X-ray diffraction）. Mesophase temperatures of MA and MB are 81.28 ~C and 54.36~C, respectively. Textures analysis by POM shows that MA was oily streak and MB was schlieren. XRD pattern shows the strongest three peaks of MA at room temperature which are （20, deg）： 2.7153, 5.2992 and 18.8500. The Strongest three peaks of MB at room temperature are （20, deg）： 9.1726, 9.7707 and 12.5389. XRD pattern of MA and MB at mesophase and above mesophase temperature that each peaks disappear.展开更多
The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Ab...The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.展开更多
文摘Copper supported over silica exhibited very high activity and selectivity for the direct synthesis of indole at atmospheric pressure. Under the reaction temperature of 325C,the yield of indole could obtain 88%.
基金supported by the National Natural Science Foundation of China(Nos.21571118&21271121)
文摘A new coordination polymer {[Cd（C_（21）H_（14）N_6）（C_8H_4O_4）]·H_2O}_n（1） was synthesized by an elaborate design via the reaction of 3-（2,6-di（pyrazin-2-yl）pyridin-4-yl）-1H-indole（bppi）,1,4-benzene-dicarboxylic acid（H2bdc） and cadmium（Ⅱ） nitrate in CH_3OH/H_2O mixed solvents. Complex 1 crystallizes in orthorhombic,space group Ccca with a = 20.012（4）,b = 31.881（6）,c = 19.808（4） ？,V = 12638（4） ？~3,Z = 16,C_（29）H_（20）CdN_6O_5,M_r = 644.91,D_c = 1.356 g·cm^（-3）,μ = 0.735 mm^（-1）,F（000） = 5184,GOOF = 1.046,the final R = 0.0405 and wR = 0.1063 for 6870 observed reflections（I 〉 2σ（I））. The Cd（Ⅱ） centre is hepta-coordinated by three N and four O atoms from one bppi terminal ligand and two bdc2– ligands,respectively,displaying a capped trigonal prism geometry. Structure extension gives coordination polymeric chains,in which the bdc2– linkers connect Cd（Ⅱ） cations into a one-dimensional（1D） coordination polymer along the c axis,giving zigzag chains with the Cd···Cd separation of 11.178（1） ？. The adjacent bppi terminal ligands in the chains are anti-periplanar conformation. The three-dimensional（3D） structure is stabilized by π···π stacking and hydrogen-bonding interactions to form a supramolecular self-penetrating network with 1D channels. In 1,there are voids 2999.7 ？~3 with 23.7% of per unit cell volume. Thermal analysis indicates that the framework of 1 is stable until 651 K and the photoluminescence of 1 in the solid shows very weak fluorescence at 382 and 560 nm upon excitation at 310 nm.
文摘Some new asymmetric thioethers 5 and 4-thiazolidinones 6 have been obtained from condensation of 5-formyl-3-(pyridin-4'-yl)-1,2,4-triazino[5,6-b] indole (3) with halogenated aromatic amines followed by addition of thiophenol and/or cycloaddition with thiolactic acids in nonpolar solvents. Structures of the products confirmed by elemental analysis and spectral measurements. The new systems obtained were evaluated as antifungal agents.
基金Supported by the National Natural Science Foundation of China(No.30672519)
文摘A novel series of ethyl 5-hydroxy-4-substituted aminomethyl-2-sulfinylmethyl-lH-indole-3-carboxylates 8a--8j and 11e--11f was synthesized and evaluated in HepG2.2.15 cells for their anti-hepatitits B virus（HBV） activity and cytotoxicity. Among them, six compounds showed more potent inhibitory activity than lamivudine. Compound 8e exhibited the most significant anti-HBV activity with an IC50 value of 1.62 μmol/L, which was 33-times more potent than the reference drug lamivudine（IC50=54.78μmol/L）.
文摘Two new indole alkaloids, named ibogamine-18-carboxylic acid, 3, 4-didehydro-7, 8-dioxo-methyl ester 1, ibogamine-18-carboxylic acid, 16, 17-didehydro-9, 17-dihydro-9-hydroxy （2-oxopropyl）-methyl ester 2, were isolated from Ervatamia hainanensis. Their structures were elucidated on the basis of spectroscopic methods.
基金supported by the research foundation of Hebei University of Science and Technology
文摘An efficient synthesis of symmetrical 2,2-bis（1H-indol-3-yl）-2H-acenaphthen-1-one is achieved via a reaction of acenaphthe-nequinone and indoles catalyzed by solid superacid SO4^2-/TiO2 under solvent-free conditions at room temperature by grinding, which provides an efficient route to the synthesis of symmetrical 2,2-bis（1H-indol-3-yl）-2H-acenaphthen-1-one.This procedure offers several advantages including solvent-free conditions,excellent yields of products,simple work-up as well as reuse of catalysts which makes it a useful and attractive protocol for the synthesis of these compounds.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA11030404)the Guangzhou Science and Technology Plan Projects(No.201510010012)the National Natural Science Foundation of China(No.21302199)
文摘A novel esterase EstC10 from Bacillus sp. CX01 isolated from the deep sea of the Western Pacific Ocean and the functionalities of EstC 10 was characterized. At present, the reports about the kinetic resolution ofracemic methyl 2-chloropropionate were quite rare. So we developed deep-sea microbial esterase EstC10 as a novel biocatalyst in the kinetic resolution of racemic methyl 2-chloropropionate and generate （R）-methyl 2-chloropropionate with high enantiomeric excess （〉99%） after the optimization of process parameters such as pH, temperature, organic co-solvents, surfactants, substrate concentration and reaction time. Notably, the optimal substrate concentration （80 mmol/L） of esterase EstC10 was higher than the kinetic resolution of another esterase, Estl2-7 （50 mmoFL）. The novel microbial esterase EstC10 identified from the deep sea was a promising green biocatalyst in the generation of （R）-methyl 2-chloropropionate as well of many other valuable chiral chemicals in industry.
基金supported by the National Natural Science of Foundation of China(No.21305060)
文摘Two coordination polymers constructed from 3,4-thiophenedicarboxylic acid and bis（2-methyl imidazole） ligands, namely, {[Cd2（tdc）2（bip）2]·7H20}n （1） and [Cd（tdc）（bib）]n （2） （Hgtdc = 3,4-thiophenedicarboxylic acid, bip = 1,3-bis-（imidazol-2-methyl）propane and bib = 1,4-bis（imidazol-2-methyl）butane）, have been synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analyses reveal that 1 exhibits a two-dimensional （2D） layered network with 3-connected （6,3） topology, which is further connected into a three- dimensional （3D） supramolecular structure by intermolecular hydrogen bonds. However, 2 features a 2D network which can be rationalized as a 4-connected sql net. The results indicate the subtle difference of auxiliary bis（imidazol-2-methyl） ligands may lead to diverse architectures. Moreover, they exhibit luminescence emission in the solid state at room temperature.
基金supported by national 863 project(Grant No.2004AA625030,2001AA620503)NNSFC(Grant No.20432030)Key Innovative Project of the Academy(Grant No.KZCX3-SW-215).
文摘A new halogenated biindole and a new apo-carotenone have been isolated from the ethanolic extract of the green alga Chaetomorpha basiretorsa Sethcell. On the basis of chemical and spectroscopic methods including 2D NMR technique, their structures have been elucidated as 4,4′-dichloro-5,5′-dibromo-7,7′-dimethoxy-2,2′-bi-1H-indole and 1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′- trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien-2-one, respectively.
基金supported by the Fundamental Research Funds for the Central Universities(lzujbky-2010-137)Lanzhou Science and Technology Bureau Program Funds(2012-2-90)
文摘The title compound, N-(2-(1H-indol-3-yl)ethyl)-2-nitroaniline(C16H15N3O2, Mr = 281.31), has been synthesized by the multicomponent reaction of milder Ullmann, and its structure was characterized by 1H NMR, 13 C NMR, IR, H RMS(ESI) and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group I2/c with a = 15.0212(10), b = 9.4911(6), c = 20.3075(13) A, β = 100.776(7)o, V = 2844.1(3)A3, Z = 8, Dc = 1.314 g/cm3, F(000) = 1184.0, μ = 0.089 mm-1, the final R = 0.0574 and w R = 0.1688 for 1701 observed reflections(I 】 2σ(I)). X-ray analysis indicates three major N(2)–H(2)···O(2), C(13)–H(13)···O(2), N(2)–H(2)···N(3) hydrogen bonds and π-π stacking interactions in the crystal structure. The preliminary biological test shows that the title compound has a good antitumor activity against A549 in vitro with the IC50 value of 35 μmol/L.
文摘The coupling reaction of 3-cyanoacetyl-2-methylindole 1a with the aromatic diazonium salts gave the corresponding arylhydrazones 2a-e. Compounds 2 were used for synthesis of 4-aminopyrazole-5-carbonitrile 4a-e and 5-amino-4-arylazo-3-pyrazoles 5a-e derivatives. Also, treatment of 3-cyanoacetyl-2-phenylindole 1b with phenyl isothiocyanate gave the corresponding thioacetanilide 7. The later compound 7 was utilized as the key intermediate for the synthesis of some new thiadiazole derivatives 9a-r. The structures of all new compounds were elucidated on the basis of elemental analysis and spectral data.
基金Supported by the Scientific and Technological Research Program of Chongqing Municipal Education Commission(KJ1601215)the Ministry of Education "Chunhui Plan"(Z2016177)
文摘The reaction mechanism of o-aminophenol, acetic acid and phosphorus oxytrichloride in one-pot to form 2-methyl benzoxazole was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the GGA/PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Two possible reaction pathways were investigated in this study. The result indicates that the reaction Re→TS1→IM1→TSA2→IMA2→TSA3→IMA3→TSA4→IMA4→TSA5→P2 is the main pathway, the activation energy of which is the lowest. Re→TS1→IM1 is the rate-limiting step, with the activation energy being 221.54 kJ·mol^(-1) and the reaction heat being 10.06 kJ·mol^(-1). The dominant product predicted theoretically is in agreement with the experiment results.
文摘It was successfully synthesized liquid crystal monomer acrylate that conjugated with two mesogens were cholesterol and p-hydroxyphenyl-2-methyl Butanoat which called MA （monomer cholesteryl acrylate） and monomer （S）-（＋）-4-（2-Methyl butanoat-l-butyloxy） phenyl 4-[1-（propenoyloxy） butyloxy] benzoate （MB）. Two monomers were characterized by DSC （differential scanning calorimetry）, POM （polarization optical microscopy） and XRD （X-ray diffraction）. Mesophase temperatures of MA and MB are 81.28 ~C and 54.36~C, respectively. Textures analysis by POM shows that MA was oily streak and MB was schlieren. XRD pattern shows the strongest three peaks of MA at room temperature which are （20, deg）： 2.7153, 5.2992 and 18.8500. The Strongest three peaks of MB at room temperature are （20, deg）： 9.1726, 9.7707 and 12.5389. XRD pattern of MA and MB at mesophase and above mesophase temperature that each peaks disappear.
文摘The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.
