Adithya Adhikari

Synthesis and antimicrobial activities of a new series of 4-S-[41-amino-51-oxo-61-substituted benzyl-41,51-dihydro-11,21,41-triazin-3-yl]mercaptoacetyl-3-arylsydnones

The synthesis of some 4-S-(4(1)-amino-5(1)-oxo-6(1)-substituted benzyl-4(1),5(1)-dihydro-1(1),2(1),4(1)-triazin-3-yl)mercaptoacetyl-3-arylsydnones by the reaction of 3-aryl-4-bromoacetylsydnones with 6-substituted-4-amino-3-mercapto-1,2,4-triazin-5-ones is described. The IR, (1)H NMR, mass spectra and elemental analysis characterized the newly synthesized compounds. The synthesized compounds were screened for their antimicrobial activity. All the compounds showed higher activity than that of standard drug during antimicrobial studies and the activity was comparable with the standard drug for antifungal activity.

Synthesis, characterization and pharmacological study of 4,5-dihydropyrazolines carrying pyrimidine moiety

A series of 5-bromo-2-(3,5-diaryl-4,5-dihydro-1H-pyrazol-1-yl)pyrimidine were prepared under conventional heating as well as microwave reaction condition. The newly synthesized compounds were characterized on the basis of elemental, spectral and single crystal X-ray studies. These new compounds were screened for their antioxidant, anti-inflammatory and analgesic activities. Some of these compounds exhibited potent biological activities compared to the standard drug.

Synthesis and Characterization of Some Novel Quinolinothiazines of Biological Interest

A series of 3-aryl-4H-5-(61/81-substituted-31-formyl-21-quinolinyl) thia-1,2,4-triazoles were prepared by the reaction of 2-chloro-3-formyl-6/8-substituted quinoline with 3-substituted 4H-5-mercapto-1,2,4-triazole. These thia-triazoles 5 on reaction with substituted acetophenone gave a novel series of 2-substituted-s-triazolo[5,1-b]-6/8-substituted quinolino-9-arylacetyl[1,3]thiazines 8 rather than the expected 1-aryl-3-[21-(5-substituted-4H-1,2,4-triazole-5-thia)-61/81-substituted quinoline-31-yl]-2-propen-1-ones 7. The new compounds were screened for their antibacterial activity against Gram-positive and Gram-negative bacteria and antifungal activity against Candida albicans. Most of the tested compounds showed significant antibacterial activity much higher than that of the standard drug Nitrofurazone. The structures of the new compounds were established based on analytical and spectral data. In a typical example, the structure of thiazine 8e was further confirmed by single crystal x-ray data.

Synthesis, characterization and biological evaluation of dihydropyrimidine derivatives

A series of dihydropyrimidines containing quinoline were prepared under conventional heating and microwave irradiation. The structures of newly synthesized compounds were established based on analytical and spectral studies. Further these compounds were evaluated for their antioxidant, antifungal and antibacterial activities. Most of the compounds showed moderate to good activity when compared with standard.

Novel One-Pot Synthesis of Aziridines Carrying Sydnone Moiety and Their Biological Studies

Abstract A novel series of 5-(3-arylsydnon-4-yl)-7-aryl-1,4-diazabicyclo[4,1,0]hept-4-enes 3a–l were prepared in a one-pot synthesis by the reaction of 2,3-dibromo-1-(3-arylsydnon-4-yl)-3-arylpropan-1-one 1a–l and 1,2-diaminoethane. The newly synthesized compounds were screened for their antibacterial and antifungal activity. GRAPHICAL ABSTRACT

Microwave-mediated synthesis of triazolothiadiazoles as anti-inflammatory, analgesic, and anti-oxidant agents

Efficient approach to the synthesis of a series of triazolothiadiazole analogs of ibuprofen has been carried out using microwave energy. Thus a series of 1,2,4-triazolo[3,4-b]-thiadiazoles 5 were synthesized starting from 4-amino-3-[1-(4-isobutylphenyl)ethyl]-5-mercapto-1,2,4-triazole 3 and different aromatic acids using phosphorous oxychloride as cyclizing agent by microwave and conventional method. Microwave irradiation reduces both time and reaction endeavors along with reduced amount of phosphorous oxychloride. In addition, preliminary results of the biological evaluation of these compounds are also reported and they found to exhibit significant antioxidant, anti-inflammatory, and analgesic activities with reduced ulcerogenicity.

(E)-3-Methyl-4-[(2-oxidoquinolin-1-ium-3-yl)methyl­eneamino]-1H-1,2,4-triazole-5(4H)-thione N,N-dimethyl­formamide solvate

The title 1,2,4-triazole compound, C13H11N5OS·C3H7NO, crystallizes as a 1:1 dimethylformamide (DMF) solvate. The main molecule exists in a trans configuration with respect to the acyclic C=N bond. An intramolecular C—H⋯S hydrogen bond generates an S(6) ring motif. In the synthesis, a proton is transferred from the O atom of a hydroxy group to the quinoline group N atom. The essentially planar triazole ring and quinoline ring system [maximum deviations of 0.001 (2) and 0.013 (2) Å, respectively] form a dihedral angle of 5.86 (9)°. In the crystal structure, molecules of (E)-4-[(2-hydroxy-3-quinolyl)methyleneamino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione are linked into R 2 2(8) centrosymmteric dimers via N—H⋯O hydrogen bonds. These dimers are further linked into an extended three-dimensional structure by the DMF solvent molecules via intermolecular N—H⋯O and C—H⋯O hydrogen bonds. The crystal structure is consolidated by two different intermolecular π–π interactions [centroid–centroid distances = 3.6593 (12) and 3.6892 (12) Å].

Ethyl 2-[(E)-4-(dimethyl-amino)benzyl-idenehydrazino]-5-nitro-benzoate.

The title compound, C18H20N4O4, exists in the E configuration with respect to the C=N bond of the methylidine unit. The dihedral angle between the two benzene rings is 9.01 (6)°. An intramolecular N—H⋯O hydrogen bond involving the benzoate unit generates an S(6) ring motif. In the crystal, the molecules are linked by weak C—H⋯O interactions into infinite chains along the b axis. These chains are further connected into sheets parallel to the ab plane which are stacked approximately along the c axis. A C—H⋯π interaction is also observed.

One-Pot Synthesis of Pyrimidinothiazolidinones and Their Anti-Inflammatory and Antimicrobial Studies

In the present investigation, we report a one-pot synthesis of the title compounds, 2-arylidene-5-(2,3,6-trimethyl-4-methoxyphenyl)-7-substituted-5H-pyrimidino-[2,3-b]thiazolidine-3-ones 6a–j and 2-(5-nitro-2-thienylidine)-5-(2,3,6-trimethyl-4-methoxyphenyl)-7-substituted-5H- pyrimidino-[2,3-b]thiazolidine-3-ones 7a–e. Thus, 6a–j and 7a–e were prepared in good yields by refluxing 4-(2,3,6-trimethyl-4-methoxyphenyl)-6-methyl/aryl-3,4-dihydropyrimidin-2-(1H)-thiones 5, monochloro acetic acid, and anhydrous sodium acetate with the appropriate aromatic aldehyde/5-nitro-2-thiophenediacetate in acetic acid/acetic anhydride medium. The structures of these new compounds were established on the basis of their analytical and spectral data. Some of the newly synthesized compounds were screened for their anti-inflammatory and antimicrobial activity. They show moderate anti-inflammatory activity, and some of them were found to be promising antibacterial and antifungal agents. Supplemental materials are available for this article. Go to the publishers online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

5-Bromo-2-[5-(4-nitro-phen-yl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl]pyrimidine.

In the title pyrazoline compound, C19H14BrN5O2, the essentially planar pyrazoline and pyrimidine rings [maximum deviations = 0.013 (1) and 0.009 (1) Å, respectively] are inclined slightly to one another, making a dihedral angle of 10.81 (10)°. The nitrobenzene unit is almost perpendicular to the attached pyrazoline ring, as indicated by the dihedral angle of 84.61 (8)°. In the crystal structure, intermolecular C—H⋯N contacts link the molecules into dimers in an antiparallel manner. These dimers are further linked into one-dimensional chains along the b axis via C—H⋯O contacts. The crystal structure is consolidated by three different intermolecular π–π interactions [range of centroid–centroid distances = 3.5160 (11)–3.6912 (11) Å].