An efficient synthesis and antimicrobial evaluation of some new pyrazoline, pyrimidine and benzodiazepine derivatives bearing 1,3,5-triazine core

ABSTRACT. In our present investigation a new class of diverse sets of acetyl pyrazolines (6a-e), amino pyrimidines (7a-e) and 1,5-benzodiazepines (8a-e) bearing 1,3,5-triazine core were synthesised from chalcones (5a-e). Treatment of chalcone with hydrazine hydrate, guanidine hydrochloride and o-phenylenediamine afforded the corresponding acetyl pyrazoline, amino pyrimidine and 1,5-benzodiazepine derivatives respectively. The structures of all the newly synthesised compounds were assigned on the basis of FTIR, 1 H NMR, 13 C NMR, mass spectral data as well as elemental analysis. In vitro antimicrobial proficiency of the title compounds were assessed against selected pathogens S. aureus MTCC 96, S. pyogeneus MTCC 442, E. coli MTCC 443 and P. aeruginosa MTCC 1688 bacteria for antibacterial activities as well as antifungal activities against C. albicans MTCC 227, A. niger MTCC 282 and A. clavatus MTCC 1323 were used. The minimum inhibitory concentration (MIC) was determined by broth dilution method and recorded at the lowest concentration inhibiting growth of the organism. Among the synthesised compounds 6b, 6c, 7b, 8b, 8d and 8e exhibited excellent antimicrobial activity and said to be the most proficient members of the series

Synthesis of pyrazoline derivatives from the 1,3-dipolar cycloadditions using α,β-unsaturated cyclohexanone derivatives

A series of 2-pyrazolines (3a-d) were obtained by reaction 1,3-dipolar cycloadditions of α,β-unsaturated cyclohexanone derivatives (2a-c) with hydrazine hydrate and 4-nitrophenylhydrazine in the presence of acetic acid and ethanol as solvents. The structures of the synthesized compounds were confirmed by spectroscopic methods; IR, 1H and 13C NMR

(E)-4-(2,5-Dimethoxy­benzyl­idene)-2-phenyl-1,3-oxazol-5(4H)-one

The central aza­lactone ring in the title compound, C18H15NO4, is planar (r.m.s. deviation 0.05, 0.12 Å) in both independent mol­ecules comprising the asymmetric unit. The benzyl­idene substituent is coplanar with this ring [dihedral angle between the planes = 1.8 (1)° in the first mol­ecule and 2.8 (1)° in the second], as is the phenyl substitutent [dihedral angle between rings = 4.6 (1) and 9.7 (1)°, respectively]

Synthesis and characterization of some novel isoxazoles and 1,5-benzothiazepines bearing s-triazine nucleus

473-476The title compounds 7a-d and 8a-d have been prepared starting from chalcones 6a-d having s-triazine nucleus. These chalcones 6a-d on cyclisation with hydroxylamine hydro- chloride in presence of alkali and 2-aminothiophenol in presence of a few drops of glacial acetic acid give isoxazoles 7a-d and 1,5-benzothiazepines 8a-d respectively. All the products have been characterized by elemental analysis, IR, 1H NMR and LCMS data

Synthesis and studies of some novel s-triazine based aminopyrimidines, isoxazoles and 1,5-benzothiazepines

1707-1712An elegant synthesis of the titled compounds 7a-e, 8a-e and 9a-e have been presented starting from chalcones 6a-e based on s-triazine nucleus. These chalcones 6a-e on cyclisation with guanidine nitrate and hydroxylamine hydrochloride in the presence of alkali give aminopyrimidines 7a-e and isoxazoles 8a-e respectively. Further these chalcones 6a-e on cyclisation with 2-aminothiophenol in the presence of few drops of glacial acetic acid give 1,5-benzothiazepines 9a-e. All the products obtained from these reactions are characterized by elemental analysis, IR, ¹H NMR and mass spectral data

Chalcones, pyrazolines and aminopyrimidines as antibacterial agents

1442-14462,4–Bis-ethylamino-6-[4'-{3"-(substitutedphenyl/2'"-furanyl)-2"-propenone-1"-yl} phenyl amino]-s-triazine 5a-d have been prepared by treating ketone 4 with different substituted aromatic and heterocyclic aldehydes in the presence of alkali. These chalcones 5a-d on cyclisation with hydrazine hydrate and guani­dine nitrate to form pyrazolines 6a-d and aminopyrimidines 7a-d respectively. The structures of the synthesized compounds have been established on the bases of IR, 1H NMR and elemental analysis. The compounds have been evaluated for antibacterial activity against E. coli, S. paratyphi-A, S. aureus and B. subtilis