Shahnaz Perveen

Synthesis of bis-Schiff bases of isatins and their antiglycation activity

Bis-Schiff bases 1-27 have been synthesized and their in vitro antiglycation potential has been evaluated. Compounds 21 (IC(50)=243.95+/-4.59microM), 20 (IC(50)=257.61+/-5.63microM), and 7 (IC(50)=291.14+/-2.53microM) showed an excellent antiglycation activity better than the standard (rutin, IC(50)=294.46+/-1.50microM). This study has identified a series of potential molecules as antiglycation agents. A structure-activity relationship has been studied, and all the compounds were characterized by spectroscopic techniques.

Schiff bases of 3-formylchromone as thymidine phosphorylase inhibitors.

3-Formylchromone (1), 3-methyl-7-hydroxychromone (2) and Schiff bases of 3-formylchromone 3-19 have been synthesized and their anti-thymidine phosphorylase inhibitory activity was evaluated. Compounds 1-19 showed a varying degree of thymidine phosphorylase inhibition with IC(50) values 19.77+/-3.25 to 480.21+/-2.34 microM. Their activity was compared with the standard 7-deazaxanthine (IC(50)=39.28+/-0.76 microM). Compound 12 showed an excellent thymidine phosphorylase inhibitory activity with an IC(50) value of 19.77+/-3.25 microM, better than the standard. Compound 4 also showed an excellent inhibitory activity (IC(50)=40.29+/-4.56 microM). The parent 3-formylchromone (1) and 3-methyl-7-hydroxychromone (2) were found to be inactive. The structures of the compounds were elucidated by using spectroscopic techniques, including (1)H NMR, EI MS, IR, UV and elemental analysis.

Synthesis and In Vitro Leishmanicidal Activity of Some Hydrazides and Their Analogues

Twenty-one hydrazides were synthesized by treating different esters with hydrazine hydrate. Substituted hydrazides were obtained by treating hydrazides with alkyl/aryl/acyl halides. Some of these compounds exhibit potential in vitro leishmanicidal activity. The structures of all the synthesized compounds were confirmed by spectroscopic analysis.

Synthesis of novel inhibitors of β-glucuronidase based on benzothiazole skeleton and study of their binding affinity by molecular docking.

Benzothiazole derivatives 1-26 have been synthesized and their in vitro β-glucuronidase potential has been evaluated. Compounds 4 (IC(50)=8.9 ± 0.25 μM), 5 (IC(50)=36.1 ± 1.80 μM), 8 (IC(50)=8.9 ± 0.38 μM), 13 (IC(50)=19.4 ± 1.00 μM), 16 (IC(50)=4.23 ± 0.054 μM), and 18 (IC(50)=2.26 ± 0.06 μM) showed β-glucuronidase activity potent than the standard (d-saccharic acid 1,4-lactone, IC(50)=48.4 ± 1.25 μM). Compound 9 (IC(50)=94.0 ± 4.16 μM) is found to be the least active among the series. All active analogs were also evaluated for cytotoxicity and none of the compounds showed any cytotoxic effect. Furthermore, molecular docking studies were performed using the gold 3.0 program to investigate the binding mode of benzothiazole derivatives. This study identifies a novel class of β-glucuronidase inhibitors.

3-Formylchromones: Potential antiinflammatory agents

The synthesis and characterization of 3-formylchromone (1) and its derivatives 2-24 and evaluation of their potential antiinflammatory activities is reported here. These compounds were characterized by (1)H NMR, EI MS, IR, and UV spectroscopic techniques and elemental analysis. The synthesized compounds were evaluated by using various in vitro and in vivo assay models for antiinflammatory activity and their effects were compared with known standard drug such as aspirin and indomethacin. Among all tested compounds, 1, 2, 5, 6, 9, 14, 16-19, 21-23, showed promising antiinflammatory activities. The results and SAR has been discussed in this report.

Synthesis of Coumarin Derivatives with Cytotoxic, Antibacterial and Antifungal Activity

The synthesis and selective biological screening of 7-hydroxy-4-methyl-2H-chromen-2-one (2), 7-hydroxy-4,5-dimethyl-2H-chromen-2-one (15) and some of their derivatives were carried out. Compound 13 was found to be most potent cytotoxic agent with LD50 = 126.69 μg/ml. In antibacterial assay the compounds showed a broad spectrum of activities. Compound 11 exhibited a very high degree of plant growth inhibition at three levels of concentration. Compound 4 showed very promising antifungal activity against Candida albicans. Compounds 12 and 13 demonstrated excellent antioxidant activity.

Synthesis and in vitro urease inhibitory activity of N,N'-disubstituted thioureas.

Thiourea derivatives (1-38) were synthesized and evaluated for their urease inhibition potential. The synthetic compounds showed a varying degree of in vitro urease inhibition with IC50 values 5.53 ± 0.02-91.50 ± 0.08 μM, most of which are superior to the standard thiourea (IC₅₀ = 21.00 ± 0.11 μM). In order to ensure the mode of inhibition of these compounds, the kinetic study of the most active compounds has been carried out. Most of these inhibitors were found to be mixed-type of inhibitors, except compounds 13 and 30 which were competitive, while compound 19 was identified as non-competitive inhibitor with Ki values between 8.6 and 19.29 μM.

Synthesis and β-glucuronidase inhibitory activity of 2-arylquinazolin-4(3H)-ones.

2-Arylquinazolin-4(3H)-ones 1-25 were synthesized by reacting anthranilamide with various benzaldehydes using CuCl2·2H2O as a catalyst in ethanol under reflux. Synthetic 2-arylquinazolin-4(3H)-ones 1-25 were evaluated for their β-glucuronidase inhibitory potential. A trend of inhibition IC50 against the enzyme in the range of 0.6-198.2μM, was observed and compared with the standard d-saccharic acid 1,4-lactone (IC50=45.75±2.16μM). Compounds 13, 19, 4, 12, 14, 22, 23, 25, 15, 8, 17, 11, 21, 1, 3, 18, 9, 2, and 24 with the IC50 values within the range of 0.6-44.0μM, indicated that the compounds have superior activity than the standard. The compounds showed no cytotoxic effects against PC-3 cells. A structure-activity relationship is established.

An immunostimulant sesquiterpene glycoside from Sphaeranthus indicus

Abstract A new sesquiterpene glycoside, sphaeranthanolide, has been isolated from the flowers of Sphaeranthus indicus . Its structure was determined by 2D-NMR and other spectroscopic techniques. The compound exhibited immune stimulating activity.

Alkaloids from Rhazya stricta

Abstract Chemical investigations of roots and leaves of Rhazya stricta have resulted in the isolation of the new indole alkaloids, 16 R -19,20- E -isositsirikine acetate, leepacine and dihydroeburnamenine, along with six known alkaloids. Among these, (−)-16 R ,21 R - O -methyleburnamine, 2-ethyl-3[2-(3-ethylpiperidino)ethyl]-indole, (20 S )-19,20-dihydrocondylocarpine and N -acetylaspidospermidine have been isolated for the first time from R. stricta . Spectral studies on (+)-21 S -eburnamenine and the glycoalkaloid strictosamide have also been undertaken.