Mohammad Iqbal Choudhary

Evaluation of bisindole as potent β-glucuronidase inhibitors: Synthesis and in silico based studies

Bisindole analogs 1-17 were synthesized and evaluated for their in vitro β-glucuronidase inhibitory potential. Out of seventeen compounds, the analog 1 (IC50=1.62±0.04 μM), 6 (IC50=1.86±0.05 μM), 10 (IC50=2.80±0.29 μM), 9 (IC50=3.10±0.28 μM), 14 (IC50=4.30±0.08 μM), 2 (IC50=18.40±0.09 μM), 19 (IC50=19.90±1.05 μM), 4 (IC50=20.90±0.62 μM), 7 (IC50=21.50±0.77 μM), and 3 (IC50=22.30±0.02 μM) showed superior β-glucuronidase inhibitory activity than the standard (d-saccharic acid 1,4-lactone, IC50=48.40±1.25 μM). In addition, molecular docking studies were performed to investigate the binding interactions of bisindole derivatives with the enzyme. This study has identified a new class of potent β-glucouronidase inhibitors.

Antiglycation, antioxidant and toxicological potential of polyphenol extracts of alligator pepper, ginger and nutmeg from Nigeria

OBJECTIVE To evaluate the antioxidant and antiglycation potential of polyphenols from three spices; alligator pepper, ginger and nutmeg. METHODS Polyphenol extracts of these spices were subjected to brine-shrimp lethality assay, phytotoxicity test, DPPH and superoxide anion radical scavenging as well as BSA-glucose antiglycation assay. RESULTS Results obtained showed that polyphenol extract of ginger has the highest antioxidant potential with IC50 0.075 and 0.070 mg/mL for DPPH and superoxide anion radical scavenging assay while alligator pepper displayed highest antiglycation activity with IC50 0.125 mg/mL. However, nutmeg extract exhibited weakest cytotoxic and phytotoxic potential with LD50 4359.70 and 1490 µg/mL respectively. CONCLUSIONS It can be concluded that the polyphenol extracts of alligator pepper, ginger and nutmeg displayed good antioxidant as well as antiglycation potential and are safe for consumption.

Salvadiol: A Novel Triterpenoid from Salvia bucharica.

Abstract Salvadiol ( 1 ), a triterpene with a novel carbon skeleton has been isolated from the hexane soluble part of Salvia bucharica and characterized by single-crystal X-ray diffraction. The NMR data were rationalized on the basis of structure 1 determined by the X-ray technique. A biogenetic pathway for salvadiol is proposed.

Cheiradone: a vascular endothelial cell growth factor receptor antagonist.

BackgroundAngiogenesis, the growth of new blood vessels from the pre-existing vasculature is associated with physiological (for example wound healing) and pathological conditions (tumour development). Vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2) and epidermal growth factor (EGF) are the major angiogenic regulators. We have identified a natural product (cheiradone) isolated from a Euphorbia species which inhibited in vivo and in vitro VEGF- stimulated angiogenesis but had no effect on FGF-2 or EGF activity. Two primary cultures, bovine aortic and human dermal endothelial cells were used in in vitro (proliferation, wound healing, invasion in Matrigel and tube formation) and in vivo (the chick chorioallantoic membrane) models of angiogenesis in the presence of growth factors and cheiradone. In all cases, the concentration of cheiradone which caused 50% inhibition (IC50) was determined. The effect of cheiradone on the binding of growth factors to their receptors was also investigated.ResultsCheiradone inhibited all stages of VEGF-induced angiogenesis with IC50 values in the range 5.20–7.50 μM but did not inhibit FGF-2 or EGF-induced angiogenesis. It also inhibited VEGF binding to VEGF receptor-1 and 2 with IC50 values of 2.9 and 0.61 μM respectively.ConclusionCheiradone inhibited VEGF-induced angiogenesis by binding to VEGF receptors -1 and -2 and may be a useful investigative tool to study the specific contribution of VEGF to angiogenesis and may have therapeutic potential.

Megastigmane, iridoid, benzyl alcohol and phenyl propanoid glycosides from the Nepalese sandalwood Osyris wightiana Wall. ex Wight

The crude ethanolic extract of the Nepalese sandalwood Osyris wightiana Wall. ex Wight, was analyzed for its bioactive chemical constituents by chromatographic and spectroscopic methods. Phenyl propanoid, benzyl alcohol, iridoid and megastiigmanes, were isolated from the butanolic fraction by the successive use of column chromatography and HPLC. They were isolated as the new source from the genus Osyris. The structures of syringin (1) and di-O-methylcrenatin (2), 8-epideoxyloganic acid (3), citroside B (4) and roseoside (5) were characterized on the basis of extensive spectroscopic data analysis of NMR, mass and other spectroscopic techniques.