Baylis–Hillman acetates were synthesized from substituted 2-chloronicotinaldehydes and were conveniently transformed into multisubstituted quinolines and cyclopenta
gquinolines on reaction with ...nitroethane or ethyl cyanoacetate via a successive S
N2′–S
NAr elimination strategy. Thus, synthesized quinolines were evaluated for antimicrobial activity and found having substantial antibacterial and antifungal activity.
Series of substituted-s-triazines (1–22) were synthesized and evaluated for their in vitro antibacterial activity against six representative Gram-positive and Gram-negative bacterial strains. Many ...compounds have displayed comparable antibacterial activity against Bacillus sphaericus and significantly active against other tested organisms with reference to streptomycin.
Synthesis of several new series of substituted s-triazines is described and evaluated for their in vitro antibacterial activity against six representative Gram-positive and Gram-negative bacterial strains. Some members of the series displayed high anti bacterial activities against tested organisms.
In-orbit Performance of UVIT and First Results Tandon, S. N.; Hutchings, J. B.; Ghosh, S. K. ...
Journal of astrophysics and astronomy,
06/2017, Letnik:
38, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The performance of the ultraviolet telescope (UVIT) on-board AstroSat is reported. The performance in orbit is also compared with estimates made from the calibrations done on the ground. The ...sensitivity is found to be within
∼
15% of the estimates, and the spatial resolution in the NUV is found to exceed significantly the design value of
1
.
8
″
and it is marginally better in the FUV. Images obtained from UVIT are presented to illustrate the details revealed by the high spatial resolution. The potential of multi-band observations in the ultraviolet with high spatial resolution is illustrated by some results.
A simple and highly efficient synthetic route has been developed for synthesis of (R)-rugulactone (1a), (6R)-((4R)-hydroxy-6-phenyl-hex-2-enyl)-5,6-dihydro-pyran-2-one (1b) and its 4S epimer 1c by ...employing proline-catalyzed alpha-aminooxylation, Sharpless epoxidation, Mitsunobu reaction as chirality introuducing steps. The antibacterial and antifungal activity of the compounds 1a, 1b and 1c were evaluated. 1a and 1b showed better antibacterial activity against Pseudomonas aeroginosa (MIC=12.5 microg/ml for 1a, 25 microg/ml for 1b) Klebsiella pneumonia (MIC=25 microg/ml for 1a). Compounds (1a, 1b, 1c) exhibited good to moderate antifungal activity.
A simple, first stereoselective total synthesis of botryolide-E has been described. The synthesis started from propylene oxide employing Jacobsen’s hydrolytic kinetic resolution (HKR), selective ...epoxide opening, sharpless asymmetric dihydroxylation, one pot acetonide deprotection and lactonization as key steps. Further, the synthesis confirms the absolute configuration of the natural product botryolide-E and we evaluated the biological behavior of natural product botryolide-E against a panel of bacteria and fungi. Botryolide-E exhibits significant potent activity against
Staphylococcus aureus (MTCC 96) (6.25
μg/ml), good against
Escherichia coli (MTCC 443) (12.5
μg/ml),
Bacillus subtilis (MTCC 441) (25
μg/ml) and compound
1 exhibited good to moderate antifungal activity.
Transitional cell carcinoma (TCC) is the commonest cancer of the bladder. Although majority of TCC can be diagnosed at an early stage and removed easily by transurethral resection of tumor (TURT), ...the management of this carcinoma is complicated due to frequent recurrences usually within 6 months to one-year period. An imbalance between the Th1 and Th2 immune responses has been attributed to immune dysregulation in various malignancies. The present study aims to evaluate the Th1 and Th2 balance in Peripheral Blood Mononuclear Cells of 41 TCC patients (20 recurrent and 21 non-recurrent) using flow cytometry. It also further assesses immunological and cellular factors influencing the anti-neoplastic activity of the TCC patients and in 21 normal healthy subjects in terms of their cytokine expression and various cell surface markers. The findings of the study revealed that the cell surface markers CD3+, CD4+ and CD8+ along with NK cells were found to be significantly lower in patients than healthy controls (p < 0.01). The mean percent expression of CD4+ was significantly lower in patients showing recurrence (23.9 +/- 9.84) as compared to patients with non-recurrence (31.1 +/- 12.27). The percentage of CD4+T-cells (mean +/- SD) producing IFN-gamma, IL-2 and TNF-alpha were statistically significantly reduced in patients (19.1 +/- 4.94, 52.3 +/- 20.86 and 12.8 +/- 4.49) as compared to healthy controls (23.3 +/- 3.67, 67.5 +/- 12.0 and 17.6 +/- 5.96 respectively), (p < 0.01, 0.018, 0.001). On the contrary, the mean levels of IL-4, IL-6 and IL-10 in patients (63.8+/-17.01, 60.4+/-14.79 and 65.7 +/- 14.84 respectively) were significantly higher as compared to healthy controls (24.4 +/- 8.77, 26.5 +/- 5.28 and 20.6 +/- 3.81 respectively), (p < 0.001). No statistically significant difference was observed in the cytokine expression between patients showing recurrence and non-recurrence. Patients with bladder cancer seem to develop a Th2 dominant status with a deficient type1 immune response. The lymphocyte evaluation along with cytokine measurement can provide a sensitive and valuable tool for evaluating the function of cell-mediated immunity in these patients and can also find application in therapeutic monitoring of bladder cancer patients as new targets for immunotherapy.
The formation of N- and O-propargylated quinazoline derivatives
2,
3 from quinazol-4-ones
1 was theoretically predicted by optimizations at B3LYP/6-31G* level, analysed kinetically and ...thermodynamically. Theoretical predictions are validated by experiment to observe the trends and found deviation. Thus, compound
1 was propargylated in basic media to obtain compound
2 and
3 in definite proportions. Each compound was further subjected to 3
+
2 cycloaddition using perfluoroalkyl azides through Click reaction under Sharpless conditions, and obtained a series of novel perfluoroalkyl-1H,1,2,3-triazol-4-yl substituted quinazolines
4,
5, and
6. All the compounds were screened for antimicrobial activity and identified potential compounds.
A series of novel perfluoroalkyl-1H, 1, 2, 3-triazol-4-yl substituted quinazolines
4,
5, and
6 were synthesized through Click reaction under Sharpless conditions and screened for antimicrobial activity to identify potential compounds. The formation of products predicted by optimizations at B3LYP/6-31G
∗ level, analysed kinetically and thermodynamically.
Display omitted
An elegant synthetic strategy was adopted for the preparation of N‐triazolo methyl substituted fluoroquinolones 4 and screened for their antimicrobial activity. The synthetic methodology starts from ...N‐propargylation of ethyl 7‐chloro‐6‐fluoro‐4‐hydroxyquinoline‐3‐carboxylate (1) followed by reaction with azides through click reaction under Sharpless conditions furnished triazole substituted quinolone ester 3. The latter quinolone esters were reacted with various secondary amines to furnish the corresponding quinolone derivatives 4. Alternatively, quinolone carboxylic derivatives 7a, 7b, 7c, 7d were prepared in two steps from triazole tagged quinolone ester. All the final products were screened against various bacterial and fungal strains. Compounds 4a, 4b, 4c and 4k showed moderate antibacterial activity, and 4f showed promising activity against fungal strains.
A series of 7-
O-alkyl amino derivatives of chrysin were prepared and their antibacterial potential is studied.
The natural product, chrysin (5,7-dihydroxy flavone), obtained from
Oroxylum indicum, ...exhibits numerous biological activities including anticancer, anti-inflammatory, and antiallergic activities. Three series of chrysin analogues were prepared, in which chrysin and heterocyclic moieties are separated by 3-carbon, 4-carbon, and 6-carbon spacers. All the derivatives were screened for antibacterial activity against a panel of susceptible and resistant Gram-positive and Gram-negative organisms. It was observed that most of the derivatives displayed significant activity as compared to their parent compound (chrysin).
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