Synthesis of linearly fused tetracyclic heterocycles through a novel base catalyzed intramolecular rearrangement involving scission of N-N bond

Synthesis of s-triazolothiadiazepinoquinolines 4a-f and the base catalyzed intramolecular facile rearrangement of 4a-f to s-triazolothiazinoquinolines 5a-f involving scission of N-N bond is reported

Synthesis and crystal structure of 1-(2-Bromo-4,5-dimethoxybenzyl)-benzod1,2,3triazole

The title compound C15H14N3O2Br, was synthesized and characterized by X-ray diffraction analysis. The compound crystallizes in triclinic crystal class in the space group P1. The cell parameters are a = 7.057(1)Å, b = 8.142(1)Å, c = 13.738(2)Å, α = 90.039(7)°, β = 96.869(5)°, γ = 108.047(8)° and Z = 2. The final residual factor R1 = 0.0513

Synthesis and antimicrobial studies of a new series of 2-4-2-(5-ethylpyridin-2-yl)ethoxyphenyl-5-substituted-1,3,4-oxadiazoles

A series of novel 2-4-2-(5-ethylpyridin-2-yl)ethoxyphenyl-5-substituted-1,3,4-oxadiazoles were synthesized by the oxidative cyclisation of hydrazones derived from 4-2-(5-ethylpyridin-2-yl)ethoxybenzaldehyde and aroylhydrazines using chloramine-T as oxidant. IR, NMR and elemental analysis characterized the newly synthesized compounds. The synthesized compounds were evaluated for their antimicrobial activity and were compared with standard drugs. The compounds demonstrated potent to weak antimicrobial activity. Out of the compounds studied, compounds 8c and 8d showed significant inhibition. Compounds 8b, 8f, 8k and 8e showed moderate activity. The minimum inhibitory concentration of the compounds was in the range of 8–26 μg ml–1 against bacteria and 8–24 μg ml–1 against fungi. The title compounds represent a novel class of potent antimicrobial agents

Synthesis of novel 3-5-ethyl-2-(2-phenoxy-ethyl)-pyridin-5-substituted isoxazoline libraries via 1,3-dipolar cycloaddition and evaluation of antimicrobial activities

A series of novel 3-5-ethyl-2-(2-phenoxy-ethyl)-pyridin-5-substituted isoxazolines were synthesized via 1,3-dipolar cycloaddition of in situ generated nitrile oxide from 4-2-(5-ethylpyridyl)-ethoxy-benzaldoxime with alkenes to obtain new heterocyclic libraries containing a pyridine moiety in addition to the isoxazoline ring. The newly synthesized compounds were screened for their antimicrobial activity and were compared with standard drugs. The compounds demonstrated potent to weak antimicrobial activity. Of the compounds studied, compounds 3c and 3f showed significant antibacterial as well as antifungal activity. Compounds 3e and 3g showed moderate activity. The title compounds represent a novel class of potent antimicrobial agents

5-Amino-3H-isobenzo­furan-1-one (5-amino­phthalide)

The title compound, Csb 8Hsb 7NOsb 2, serves as an intermediate for the synthesis of citalopram. The packing of the planar mol-ecules is stabilized by N-H⋅sO and N-H⋅sN hydrogen bonds

Influence of Moisture Absorption and Content of Graphite Filler on Electrical Property of Sensors and Transducers Enclosures and Phenomena of Electrostriction in Glass- Epoxy Composites

In this investigation E-glass epoxy composite filled with different amount of graphite particles were prepared by compression. Plain waived E-glass cloth with density 200g / meter square was used as reinforcement. Epoxy resin LY556 mixed with Hardener HT907 and accelerator DY063 in the ratio 100:80:2 were used as matrix. The graphite of 50 particle size was used as fillers. Four types of composites were prepared with different amount of graphite fillers viz 0 %, 3 %, 6 % and 9 % with unchanged reinforcement. After subjecting the samples to water absorption up to 96 hours in steps of 24 hrs, dielectric dissipation factor (tan δ), dielectric constant and a. c. conductivity have been measured by using a LCR meter at two different frequencies (100 Hz and 1 kHz). Results show that tan δ direct constant, a.c. conductivity increases with increase in % of graphite in the composites at both high and low frequency for dry samples. Samples with 24 hrs moisture absorption showed approximately same result. After 48 hrs, tan δ values showed variations. However, the fluctuations were less at 6 % of graphite in all samples after 48 and 72 hrs of moisture absorption. Dielectric constant increases with increase in graphite % in composites at higher frequency and there was not much variation at low frequency. In all samples after 24 and 48 hrs of moisture absorption, dielectric constant decreases with increase in graphite loading. It is observed that dielectric constant increases in all samples after 72 hrs of moisture absorption as compared to dry samples. A c. conductivity increases with increase in % of graphite content in dry sample. Up to 6% a. c. conductivity increases after 24 and 48 hrs of immersion, after 72 hrs the trend is reversed. Since Fermi level is initially shifted towards the conduction band and then after 72 hrs of moisture absorption shifted towards the valence band. a. c. conductivity increases with increase in moisture content. The phenomenon of electrostriction was observed in composites without graphite fillers

Hydrothermal Synthesis and Characterization of High Quality Graphene Oxide for Efficient Photodegradation of Dyes

The title compound, Csb 8Hsb 7NOsb 2, serves as an intermediate for the synthesis of citalopram. The packing of the planar mol-ecules is stabilized by N-H⋅sO and N-H⋅sN hydrogen bonds

Crystal structure of 4-Amino-3-(4′-chlorophenyl)-4-H-[1,2,4]-triazolo-5-thiol

The crystal structure of 4-amino-3-(4′-chlorophenyl)-4H-[1,2,4]-triazolo-5-thiol (ACPTT) was determined by crystallographic methods. There are two crystallographically independent molecules in the asymmetric unit and are related by pseudo inversion symmetry with each other. A number of C-H…N and N-H…N types of intermolecular interactions stabilize the molecules in the unit cell in addition to van der Waals forces

Design, synthesis, and pharmacological studies of some new Mannich bases and S-alkylated analogs of pyrazole integrated 1,3,4-oxadiazole

A facile and convenient synthesis of Mannich bases 5a–f and S-alkylated derivatives 6a–f and 7a–f has been carried out from the key intermediate 5-(5-methyl-1-phenyl-1H-pyrazol-4-yl)-1,3,4-oxadiazole-2(3H)-thione (4). Intermediate 4 was obtained from one-pot reaction of ethyl acetoacetate, phenylhydrazine, and N,N-dimethylformamide dimethyl acetal (DMF-DMA) followed by reaction with hydrazine hydrate and carbon disulfide. The structure of the newly synthesized compounds was established on the basis of elemental analysis, infrared (IR), 1H nuclear magnetic resonance (NMR), 13C NMR, and mass spectroscopic data. All synthesized compounds were screened for in vivo antiinflammatory, in vivo analgesic, and in vitro antimicrobial activity. From the activity studies, it was concluded that, among all the derivatives, compounds 5c, 5e, 5f, 6c, 7b, and 7c showed potent antiinflammatory activity, whereas 5b, 5c, 5e, 5f, 6c, 6f, 7b, 7c, and 7e exhibited good analgesic activity. Compounds 6a, 6c, 7b, 7c, and 7d showed maximum activity against the bacterial strains. Efforts were also made to establish structure–activity relationships among the tested compounds

Synthesis of pharmaceutically important condensed heterocyclic 4,6-disubstituted-1,2,4-triazolo-1,3,4-thiadiazole derivatives as antimicrobials

The two series of 4,6-disubstituted 1,2,4-triazolo-1,3,4-thiadiazole derivatives 2(a–e) and 3(a–e) were synthesized and characterized using IR, 1H-NMR, CHNS analysis and by single crystal X-ray crystallographic studies. The compound 6-(2-chloro-phenyl)-3-ethyl-1,2,4triazole3,4-bthiadiazole 2b has been characterized by single crystal X-ray diffraction method. The compound crystallizes in monoclinic space group P21/c with a cell parameters a=11.879(1) Å, b=15.112(2) Å, c=13.95(2) Å, Z=8 and the final R factor is R1=0.0524. The structure exhibits both intra and intermolecular hydrogen bonds. The title compounds were checked for their efficacy as antimicrobials in vitro. Compounds 2b, 2c, 2d, 3b, 3c and 3d showed significant inhibition against all the strains tested, when compared to standard drugs