ABSTRACT The synthesis of a hybrid material obtained by electropolymerization of a solution of py... more ABSTRACT The synthesis of a hybrid material obtained by electropolymerization of a solution of pyrrole and [NEt4]2[Ni(dmit)2] (dmit = 1,3-dithiole-2-thione-4,5-dithiolato) in acetonitrile solution is reported. The material was characterized by cyclic voltammetry, UV–vis and infrared spectroscopies, scanning electron microscopy (SEM), atomic force microscopy (AFM) and thermal gravimetric analysis (TGA). The FTIR spectroscopy showed that the [Ni(dmit)2]2− anion has been inserted in the polypyrrole framework and was not destroyed or modified during the polymerization process. The voltammetric analysis indicated that the material has electroactivity and undergoes redox processes associated with the conducting polymer and the counteranion. The cyclic voltammetry results also suggest that the counteranion is not trapped in the PPy matrix undergoing anion exchange during the redox cycle of PPy. The PPy/[Ni(dmit)2]2− exhibits good thermal stability and a intrinsic conductivity value in the range of semiconductors (10−3 S cm−1).
Background: Near to 5-7 million people are infected with T. cruzi in the world, and about 10,000 ... more Background: Near to 5-7 million people are infected with T. cruzi in the world, and about 10,000 people per year die of problems associated with this disease. Method: Herein, the synthesis, antitrypanosomal and antimycobacterial activities of seventeen coumarinic N-acylhydrazonic derivatives have been reported. Results: These compounds were synthesized using methodology with reactions global yields ranging from 46%-70%. T. cruzi in vitro effects were evaluated against trypomastigote and amastigote, forming M. tuberculosis activity towards H37Rv sensitive strain and resistant strains. Discussion: Against T. cruzi, the more active compounds revealed only moderate activity IC50/96h~20 μM for both trypomastigotes and amastigotes intracellular forms. (E)-2-oxo-N'- (3,4,5-trimethoxybenzylidene)-2H-chromene-3-carbohydrazide showed meaningful activity in INH resistant/RIP resistant strain. Conclusion: These compound acting as multitarget could be good leads for the development of new tr...
Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinoli... more Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinolines.-A new series of 2,4-disubstituted quinolines (IX) (46 examples) is synthesized starting from inexpensive isatin. Derivatives (IXe) and (IXf) exhibit 99% inhibition against drug-sensitive and > 90% inhibition against isoniazid resistant M. tuberculosis H27Rs strains.-(NAYYAR, A.
Related Article: Nubia Boechat, Luiz C. S. Pinheiro, Angelo C. Pinto, Thiago S. Silva, James L. W... more Related Article: Nubia Boechat, Luiz C. S. Pinheiro, Angelo C. Pinto, Thiago S. Silva, James L. Wardell, Solange M. S. V. Wardell|2014|Z.Kristallogr.|229|459|doi:10.1515/zkri-2014-1740
Abstract The crystal structures of four 1-aryl-[1,2,4]triazolo[4,3-a]quinoxaline derivatives, 2, ... more Abstract The crystal structures of four 1-aryl-[1,2,4]triazolo[4,3-a]quinoxaline derivatives, 2, are reported: [aryl = 3-ClC6H4: 2a; 2-HOC6H4:2b;2,3-(HO)2C6H3: 2c; and 3,4-(MeO)2C6H3: 2d] The compounds, 2, were prepared by oxidation of substituted arenealdehyde quinoxalin-2-ylhydrazones, 1, using ferric chloride in alcohol. In each of the four compounds, the three ring -[1,2,4]triazolo[4,3-a]quinoxaline moiety is a near planar moiety, with all ring atoms within 0.1 A of the best plane. There are large dihedral angles, 59 ± 7°, between the [1,2,4]triazolo[4,3-a]quinoxaline system and the phenyl ring. The ortho sited hydroxyl groups in 2c are jointly involved in a single O H⋯O intramolecular hydrogen bond and individually in O H⋯N intermolecular interactions, while the hydroxyl group in 2b is involved in an intermolecular O H⋯N hydrogen bond. These and weaker intermolecular interactions, including some of C H···Z (Z = O, N and or π) and π···π interactions generate the supramolecular arrangements in 2b and 2c. Intermolecular C H···Z (Z = O, N and or π) and π···π interactions are only present in 2a and 2d.
Abstract A combined structural and computational study has been conducted on two chalcone compoun... more Abstract A combined structural and computational study has been conducted on two chalcone compounds, namely (E)-3-(4-bromophenyl)-1-(4,8-dimethoxynaphthalen-1-yl)prop-2-en-1-one (1), and (E)-3-(3,4-dichlorophenyl)-1-(4,8-dimethoxynaphthalen-1-yl)prop-2-en-1-one (2). These compounds are members of a series of compounds identified from a molecular modelling study as potentially active Mycobacterium tuberculosis Enoyl ACP reductase (InhA) inhibitors. In addition, the computational study indicated that the compounds have potential as optical materials. The combined study revealed that both molecules in the solid state displayed similar overall molecular conformations between a ‘‘T’’ and a ‘‘Y’’ shape, but with different arrangements in the bridging prop-2-en-1-one unit: an anti-periplanar in 1 and a syn-periplanar in 2. The experimental and calculated bond lengths and angles for anti-periplanar 1 and syn-periplanar 2 were generally in good agreement.Theoretical calculations at the B3LYP/DGTZVP level in the gas phase, DMSO and water media indicated that for both compounds, the syn-periplanar form was the energy local minimum while the anti-periplanar form was the energy global minimum. However, the energy differences are very small, with slight variations when using the different basis sets (0.80 and 0.84 kcal/mol using the B3LYP/DGTVP theory level in gas phase, 0.28 and 0.32 in DMSO and 0.27 and 0.31 kcal/mol in water). The differences in the solid state arrangements within the bridging prop-2-en-1-one unit in 1 and 2 arise from variations in the intermolecular interactions, with halogen bonds being considered to be an important factor in stabilizing a syn-periplanar arrangement in compound 2. PLATON and Hirshfeld surface analyses confirmed the important intermolecular interactions in 1 and 2. Calculations were also carried out on the electronic and vibrational spectra, dipole moments and charge distributions of 1 and 2. The HOMO was located in the dimethoxynaphthalenyl region of the molecule with mild donor character, while the LUMO was located in the propenyl and phenyl regions of each molecule. The energy gaps between these orbitals are 3.35 eV for 1 3.25 eV for 2. The delocalization present in compounds 1 and 2 facilitates the HOMO-LUMO charge transfer process. The total electronic molecular dipolar moments (μTotal) were calculated to be 4.1511 and 5.9316 D for 1 and 2, respectively. The values of μTotal found for 1 and 2 are both larger than reported values for similar compounds, indicating that the compounds studied here should exhibit a good non-linear optical response.
Coumarins are a class of natural and synthetic products with a wide variety of applications in di... more Coumarins are a class of natural and synthetic products with a wide variety of applications in different fields. Due to the general importance of coumarins, the objective of this work is to further develop the chemistry of 1-(2-hydroxy-2-methyl-2H-chromen-3yl)ethanone, 1, a potentially useful and versatile coumarin but an under-reported compound in the literature. This work describes a green preparation of 1 in the absence of solvents and acids, thereby eliminating byproducts, normally obtained in classical procedures, and a mechanistic study of the reactions of 1 with nucleophiles. In addition, we report the characterisation of 1-(2-ethoxy-2-methyl-2H-chromen-3-yl)ethanone 2, via X-ray crystallography and 2D NMR spectra.
Synthesis, potent anti-TB activity against M. tuberculosis ATTC 27294, crystal structures and com... more Synthesis, potent anti-TB activity against M. tuberculosis ATTC 27294, crystal structures and complex formation of selected 2-arylidenehydrazinylbenzothiazole derivatives.
Parallel, offset π[C(=O)N(H)N=C] … π(phenyl) interactions are observed in the crystal of (2thieny... more Parallel, offset π[C(=O)N(H)N=C] … π(phenyl) interactions are observed in the crystal of (2thienyl)CH2CON(H)-N=C(H)Ph, along with more conventional non-covalent interactions. All notable interactions have been analysed by the calculated Hirshfeld surfaces, NCI plots and QTAIM analysis. The π[C(=O)N(H)N=C] … π(phenyl) interactions, whereby the N(H) atom lies over the ring centroid and with the N and C atoms on either side of the N(H) atom closely overlay 1,3-carbon atoms of the phenyl ring, are shown to be attractive. Theory suggests the energy of association provided the π[C(=O)N(H)N=C] … π(phenyl) interaction to the molecular packing to be about 15 kJ/mol, a value similar to that provided by similarly orientated benzene 2 and pyridine rings. A survey of the literature of related structures suggests comparable interactions occur in approximately 5-6% of crystals where they can potentially occur. Footnote † Electronic supplementary information (ESI) available: HRMS spectrum, diagrams of analogous π[C=NN(H)C(=O)] … π(phenyl) interactions occurring literature crystals along with full bibliographic details and selected geometric parameters. CCDC 2036031 contains the supplementary crystallographic data for this paper. For ESI and crystallographic data in CIF or other electronic format see
Acta Crystallographica Section E: Crystallographic Communications, May 17, 2022
The crystal structures of four thiophene-carbohydrazide-pyridine derivatives, viz. N'-[(E)-pyridi... more The crystal structures of four thiophene-carbohydrazide-pyridine derivatives, viz. N'-[(E)-pyridin-3-ylmethylidene]thiophene-2-carbohydrazide, C 11 H 9 N 3 OS, (I), N 0-[(E)-pyridin-2-ylmethylidene]thiophene-2-carbohydrazide, C 11 H 9 N 3 OS, (II), N-methyl-N 0-[(E)-pyridin-2-ylmethylidene]thiophene-2-carbohydrazide, C 12 H 11 N 3 OS, (III) and N 0-[(E)-pyridin-2-ylmethylidene]-2-(thiophen-2-yl)ethanohydrazide, C 12 H 11 N 3 OS, (IV) are described. The dihedral angles between the thiophene ring and the pyridine ring are 21.4 (2), 15.42 (14), 4.97 (8) and 83.52 (13) for (I)-(IV), respectively. The thiophene ring in (IV) is disordered over two orientations in a 0.851 (2):0.149 (2) ratio. Key features of the packing include N-HÁ Á ÁN p (p = pyridine) hydrogen bonds in (I), which generate C(7) chains propagating in the [001] direction; N-HÁ Á ÁN p links also feature in (II), but in this case they lead to C(6) [001] chains; in (IV), classical amide (C4) N-HÁ Á ÁO links result in [010] chains; in every case adjacent molecules in the chains are related by 2 1 screw axes. There are no classical hydrogen bonds in the extended structure of (III). Various weak C-HÁ Á ÁX (X = O, N, S) interactions occur in each structure, but no aromaticstacking is evident. The Hirshfeld surfaces and fingerprint plots for (I)-(IV) are compared.
Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinoli... more Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinolines.-A new series of 2,4-disubstituted quinolines (IX) (46 examples) is synthesized starting from inexpensive isatin. Derivatives (IXe) and (IXf) exhibit 99% inhibition against drug-sensitive and > 90% inhibition against isoniazid resistant M. tuberculosis H27Rs strains.-(NAYYAR, A.
The synthesis and anti-tubercular activity of series of acyl hydrazonyl compounds, namely (E)-N'-... more The synthesis and anti-tubercular activity of series of acyl hydrazonyl compounds, namely (E)-N'-(arylidene)thiophen-2-carbohydrazide, (E)-N'-(arylidene)furan-2-carbohydrazide, (E)-N-methyl-N'-arylidenethiophen-2-carbohydrazide, and E)-N-methyl-N'-arylidene-2-(thien-2yl)-acetohydrazide, [32 compounds in all] are reported. The activities of against Mycobacterium tuberculosis H37Rv (ATTC27294) are compared with those (E)-N'-arylidene-2-(thien-2-yl)-acetohydrazide, previously reported. The most active compounds are (aryl = 5-nitrothien-2-yl), (aryl = 5-nitrofuran-2-yl) and (aryl = 5-nitrothien-2-yl). Moderate activity was displayed by (aryl = 5-nitrofuran-2-yl) and certain derivatives of series where aryl is pyridin-2-yl or an o-hydroxyphenyl derivative. Doubling of certain NMR signals of each compound in solution indicates that a mixture of conformers, Z C(O)NH /E (C=N) and E C(O)NH /E (C=N) about the C(O)-NH-N=C(H, aryl) fragment is present. In contrast, only one form for each compound is present in solution from the single set of NMR signals. It is suggested that this form in solution is the E C(O)NH /E (C=N) form. Only a single set of NMR signals are found for the N-methylated derivatives.
ABSTRACT The synthesis of a hybrid material obtained by electropolymerization of a solution of py... more ABSTRACT The synthesis of a hybrid material obtained by electropolymerization of a solution of pyrrole and [NEt4]2[Ni(dmit)2] (dmit = 1,3-dithiole-2-thione-4,5-dithiolato) in acetonitrile solution is reported. The material was characterized by cyclic voltammetry, UV–vis and infrared spectroscopies, scanning electron microscopy (SEM), atomic force microscopy (AFM) and thermal gravimetric analysis (TGA). The FTIR spectroscopy showed that the [Ni(dmit)2]2− anion has been inserted in the polypyrrole framework and was not destroyed or modified during the polymerization process. The voltammetric analysis indicated that the material has electroactivity and undergoes redox processes associated with the conducting polymer and the counteranion. The cyclic voltammetry results also suggest that the counteranion is not trapped in the PPy matrix undergoing anion exchange during the redox cycle of PPy. The PPy/[Ni(dmit)2]2− exhibits good thermal stability and a intrinsic conductivity value in the range of semiconductors (10−3 S cm−1).
Background: Near to 5-7 million people are infected with T. cruzi in the world, and about 10,000 ... more Background: Near to 5-7 million people are infected with T. cruzi in the world, and about 10,000 people per year die of problems associated with this disease. Method: Herein, the synthesis, antitrypanosomal and antimycobacterial activities of seventeen coumarinic N-acylhydrazonic derivatives have been reported. Results: These compounds were synthesized using methodology with reactions global yields ranging from 46%-70%. T. cruzi in vitro effects were evaluated against trypomastigote and amastigote, forming M. tuberculosis activity towards H37Rv sensitive strain and resistant strains. Discussion: Against T. cruzi, the more active compounds revealed only moderate activity IC50/96h~20 μM for both trypomastigotes and amastigotes intracellular forms. (E)-2-oxo-N'- (3,4,5-trimethoxybenzylidene)-2H-chromene-3-carbohydrazide showed meaningful activity in INH resistant/RIP resistant strain. Conclusion: These compound acting as multitarget could be good leads for the development of new tr...
Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinoli... more Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinolines.-A new series of 2,4-disubstituted quinolines (IX) (46 examples) is synthesized starting from inexpensive isatin. Derivatives (IXe) and (IXf) exhibit 99% inhibition against drug-sensitive and > 90% inhibition against isoniazid resistant M. tuberculosis H27Rs strains.-(NAYYAR, A.
Related Article: Nubia Boechat, Luiz C. S. Pinheiro, Angelo C. Pinto, Thiago S. Silva, James L. W... more Related Article: Nubia Boechat, Luiz C. S. Pinheiro, Angelo C. Pinto, Thiago S. Silva, James L. Wardell, Solange M. S. V. Wardell|2014|Z.Kristallogr.|229|459|doi:10.1515/zkri-2014-1740
Abstract The crystal structures of four 1-aryl-[1,2,4]triazolo[4,3-a]quinoxaline derivatives, 2, ... more Abstract The crystal structures of four 1-aryl-[1,2,4]triazolo[4,3-a]quinoxaline derivatives, 2, are reported: [aryl = 3-ClC6H4: 2a; 2-HOC6H4:2b;2,3-(HO)2C6H3: 2c; and 3,4-(MeO)2C6H3: 2d] The compounds, 2, were prepared by oxidation of substituted arenealdehyde quinoxalin-2-ylhydrazones, 1, using ferric chloride in alcohol. In each of the four compounds, the three ring -[1,2,4]triazolo[4,3-a]quinoxaline moiety is a near planar moiety, with all ring atoms within 0.1 A of the best plane. There are large dihedral angles, 59 ± 7°, between the [1,2,4]triazolo[4,3-a]quinoxaline system and the phenyl ring. The ortho sited hydroxyl groups in 2c are jointly involved in a single O H⋯O intramolecular hydrogen bond and individually in O H⋯N intermolecular interactions, while the hydroxyl group in 2b is involved in an intermolecular O H⋯N hydrogen bond. These and weaker intermolecular interactions, including some of C H···Z (Z = O, N and or π) and π···π interactions generate the supramolecular arrangements in 2b and 2c. Intermolecular C H···Z (Z = O, N and or π) and π···π interactions are only present in 2a and 2d.
Abstract A combined structural and computational study has been conducted on two chalcone compoun... more Abstract A combined structural and computational study has been conducted on two chalcone compounds, namely (E)-3-(4-bromophenyl)-1-(4,8-dimethoxynaphthalen-1-yl)prop-2-en-1-one (1), and (E)-3-(3,4-dichlorophenyl)-1-(4,8-dimethoxynaphthalen-1-yl)prop-2-en-1-one (2). These compounds are members of a series of compounds identified from a molecular modelling study as potentially active Mycobacterium tuberculosis Enoyl ACP reductase (InhA) inhibitors. In addition, the computational study indicated that the compounds have potential as optical materials. The combined study revealed that both molecules in the solid state displayed similar overall molecular conformations between a ‘‘T’’ and a ‘‘Y’’ shape, but with different arrangements in the bridging prop-2-en-1-one unit: an anti-periplanar in 1 and a syn-periplanar in 2. The experimental and calculated bond lengths and angles for anti-periplanar 1 and syn-periplanar 2 were generally in good agreement.Theoretical calculations at the B3LYP/DGTZVP level in the gas phase, DMSO and water media indicated that for both compounds, the syn-periplanar form was the energy local minimum while the anti-periplanar form was the energy global minimum. However, the energy differences are very small, with slight variations when using the different basis sets (0.80 and 0.84 kcal/mol using the B3LYP/DGTVP theory level in gas phase, 0.28 and 0.32 in DMSO and 0.27 and 0.31 kcal/mol in water). The differences in the solid state arrangements within the bridging prop-2-en-1-one unit in 1 and 2 arise from variations in the intermolecular interactions, with halogen bonds being considered to be an important factor in stabilizing a syn-periplanar arrangement in compound 2. PLATON and Hirshfeld surface analyses confirmed the important intermolecular interactions in 1 and 2. Calculations were also carried out on the electronic and vibrational spectra, dipole moments and charge distributions of 1 and 2. The HOMO was located in the dimethoxynaphthalenyl region of the molecule with mild donor character, while the LUMO was located in the propenyl and phenyl regions of each molecule. The energy gaps between these orbitals are 3.35 eV for 1 3.25 eV for 2. The delocalization present in compounds 1 and 2 facilitates the HOMO-LUMO charge transfer process. The total electronic molecular dipolar moments (μTotal) were calculated to be 4.1511 and 5.9316 D for 1 and 2, respectively. The values of μTotal found for 1 and 2 are both larger than reported values for similar compounds, indicating that the compounds studied here should exhibit a good non-linear optical response.
Coumarins are a class of natural and synthetic products with a wide variety of applications in di... more Coumarins are a class of natural and synthetic products with a wide variety of applications in different fields. Due to the general importance of coumarins, the objective of this work is to further develop the chemistry of 1-(2-hydroxy-2-methyl-2H-chromen-3yl)ethanone, 1, a potentially useful and versatile coumarin but an under-reported compound in the literature. This work describes a green preparation of 1 in the absence of solvents and acids, thereby eliminating byproducts, normally obtained in classical procedures, and a mechanistic study of the reactions of 1 with nucleophiles. In addition, we report the characterisation of 1-(2-ethoxy-2-methyl-2H-chromen-3-yl)ethanone 2, via X-ray crystallography and 2D NMR spectra.
Synthesis, potent anti-TB activity against M. tuberculosis ATTC 27294, crystal structures and com... more Synthesis, potent anti-TB activity against M. tuberculosis ATTC 27294, crystal structures and complex formation of selected 2-arylidenehydrazinylbenzothiazole derivatives.
Parallel, offset π[C(=O)N(H)N=C] … π(phenyl) interactions are observed in the crystal of (2thieny... more Parallel, offset π[C(=O)N(H)N=C] … π(phenyl) interactions are observed in the crystal of (2thienyl)CH2CON(H)-N=C(H)Ph, along with more conventional non-covalent interactions. All notable interactions have been analysed by the calculated Hirshfeld surfaces, NCI plots and QTAIM analysis. The π[C(=O)N(H)N=C] … π(phenyl) interactions, whereby the N(H) atom lies over the ring centroid and with the N and C atoms on either side of the N(H) atom closely overlay 1,3-carbon atoms of the phenyl ring, are shown to be attractive. Theory suggests the energy of association provided the π[C(=O)N(H)N=C] … π(phenyl) interaction to the molecular packing to be about 15 kJ/mol, a value similar to that provided by similarly orientated benzene 2 and pyridine rings. A survey of the literature of related structures suggests comparable interactions occur in approximately 5-6% of crystals where they can potentially occur. Footnote † Electronic supplementary information (ESI) available: HRMS spectrum, diagrams of analogous π[C=NN(H)C(=O)] … π(phenyl) interactions occurring literature crystals along with full bibliographic details and selected geometric parameters. CCDC 2036031 contains the supplementary crystallographic data for this paper. For ESI and crystallographic data in CIF or other electronic format see
Acta Crystallographica Section E: Crystallographic Communications, May 17, 2022
The crystal structures of four thiophene-carbohydrazide-pyridine derivatives, viz. N'-[(E)-pyridi... more The crystal structures of four thiophene-carbohydrazide-pyridine derivatives, viz. N'-[(E)-pyridin-3-ylmethylidene]thiophene-2-carbohydrazide, C 11 H 9 N 3 OS, (I), N 0-[(E)-pyridin-2-ylmethylidene]thiophene-2-carbohydrazide, C 11 H 9 N 3 OS, (II), N-methyl-N 0-[(E)-pyridin-2-ylmethylidene]thiophene-2-carbohydrazide, C 12 H 11 N 3 OS, (III) and N 0-[(E)-pyridin-2-ylmethylidene]-2-(thiophen-2-yl)ethanohydrazide, C 12 H 11 N 3 OS, (IV) are described. The dihedral angles between the thiophene ring and the pyridine ring are 21.4 (2), 15.42 (14), 4.97 (8) and 83.52 (13) for (I)-(IV), respectively. The thiophene ring in (IV) is disordered over two orientations in a 0.851 (2):0.149 (2) ratio. Key features of the packing include N-HÁ Á ÁN p (p = pyridine) hydrogen bonds in (I), which generate C(7) chains propagating in the [001] direction; N-HÁ Á ÁN p links also feature in (II), but in this case they lead to C(6) [001] chains; in (IV), classical amide (C4) N-HÁ Á ÁO links result in [010] chains; in every case adjacent molecules in the chains are related by 2 1 screw axes. There are no classical hydrogen bonds in the extended structure of (III). Various weak C-HÁ Á ÁX (X = O, N, S) interactions occur in each structure, but no aromaticstacking is evident. The Hirshfeld surfaces and fingerprint plots for (I)-(IV) are compared.
Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinoli... more Quinoline derivatives R 0410 Synthesis and Antituberculosis Activity of 2,4-Disubstituted Quinolines.-A new series of 2,4-disubstituted quinolines (IX) (46 examples) is synthesized starting from inexpensive isatin. Derivatives (IXe) and (IXf) exhibit 99% inhibition against drug-sensitive and > 90% inhibition against isoniazid resistant M. tuberculosis H27Rs strains.-(NAYYAR, A.
The synthesis and anti-tubercular activity of series of acyl hydrazonyl compounds, namely (E)-N'-... more The synthesis and anti-tubercular activity of series of acyl hydrazonyl compounds, namely (E)-N'-(arylidene)thiophen-2-carbohydrazide, (E)-N'-(arylidene)furan-2-carbohydrazide, (E)-N-methyl-N'-arylidenethiophen-2-carbohydrazide, and E)-N-methyl-N'-arylidene-2-(thien-2yl)-acetohydrazide, [32 compounds in all] are reported. The activities of against Mycobacterium tuberculosis H37Rv (ATTC27294) are compared with those (E)-N'-arylidene-2-(thien-2-yl)-acetohydrazide, previously reported. The most active compounds are (aryl = 5-nitrothien-2-yl), (aryl = 5-nitrofuran-2-yl) and (aryl = 5-nitrothien-2-yl). Moderate activity was displayed by (aryl = 5-nitrofuran-2-yl) and certain derivatives of series where aryl is pyridin-2-yl or an o-hydroxyphenyl derivative. Doubling of certain NMR signals of each compound in solution indicates that a mixture of conformers, Z C(O)NH /E (C=N) and E C(O)NH /E (C=N) about the C(O)-NH-N=C(H, aryl) fragment is present. In contrast, only one form for each compound is present in solution from the single set of NMR signals. It is suggested that this form in solution is the E C(O)NH /E (C=N) form. Only a single set of NMR signals are found for the N-methylated derivatives.
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