Three triorganotin (IV) cyclopentane carboxylates were synthesized and structurally characterized by in solid state by Fourier‐transform infrared spectroscopy and single crystal diffraction, and in solution by NMR (1H,13C, and119Sn) spectroscopy. The complexes were tested for their anticancer activity against MCF‐7 and HeLa cells along with normal BHK‐21 cells. As revealed by MTT assay, complex
As part of ongoing efforts to isolate biologically active fungal metabolites, a cyclic pentapeptide, sheptide A (
- PAR ID:
- 10464035
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- The Journal of Antibiotics
- Volume:
- 76
- Issue:
- 11
- ISSN:
- 0021-8820
- Format(s):
- Medium: X Size: p. 642-649
- Size(s):
- p. 642-649
- Sponsoring Org:
- National Science Foundation
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2 was identified as the most potent derivative with an IC50value of 2.59 and 0.051 μM against HeLa and MCF‐7 cells, respectively. The results were compared with cisplatin as reference drug. Fluorescent microscopic studies using 4′,6‐diamidino‐2‐phenylindole (DAPI) and propidium iodide (PI) staining confirmed the occurrence of apoptosis in HeLa cells treated with the most active complex2 . The complex2 also triggered the release of lactate dehydrogenase (LDH) in treated HeLa and MCF‐7 cells whereas a luminescence assay displayed a remarkable increase in the activity of caspase‐9 and ‐3. Moreover, flow cytometric results revealed that complex2 caused G0/G1 arrest in the treated HeLa cells. The complexes were further screened for DNA binding studies through UV‐vis spectroscopy and cyclic voltammetry. The high activity of complex2 was attributed to its higher Lewis acidity as indicated by natural bond orbital (NBO) analysis. Theoretical modelling and molecular docking studies were also conducted to study the reactivity of complexes againstVEGFR 2 Kinase . -
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ABSTRACT Malaria continues to be a serious and debilitating disease. The emergence and spread of high‐level resistance to multiple antimalarial drugs by
Plasmodium falciparum has brought about an urgent need for new treatments that will be active against multidrug resistant malaria infections. One such treatment,ELQ‐331 (MMV‐167), an alkoxy carbonate prodrug of 4(1H )‐quinoloneELQ‐300 , is currently in preclinical development with the Medicines for Malaria Venture. Clinical development ofELQ‐331 or similar compounds will require the availability of isotopically labeled analogs. Unfortunately, a suitable method for the deuteration of these important compounds was not found in the literature. Here, we describe a facile and scalable method for the deuteration of 4(1H )‐quinoloneELQ‐300 , its alkoxycarbonate prodrugELQ‐331 , and their respective N‐oxides using deuterated acetic acid. -
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Abstract BACKGROUND Larvae of the diamond back moth (DBM),
Plutella xylostella , are destructive cabbage pests causing economic losses worldwide. Continuous application of synthetic pesticides to control this pest has resulted in environmental pollution and resistant pest strains. Thus, there is a crucial need to seek natural alternatives with minimal detrimental effects. This study was designed to investigate the antifeedant activities of endophytic fungi ofCyperus iria Diaporthe miriciae fungus.RESULTS Two cyclohexeneoxidediones, phyllostine acetate (
1 ) and phyllostine (2 ), isolated from an ethyl acetate extract ofD. miriciae exhibited strong antifeedant, contact toxicity, and oviposition deterrent activities againstP. xylostella . Phyllostine acetate (1 ) and phyllostine (2 ) showed feeding deterrent indexes of 100% at 50 μg cm−2in the no‐choice leaf disc assay and 50% feeding deterrence (DC50) values of 9 and 4.7 μg cm−2respectively. The median lethal concentration (LC50) values of phyllostine acetate (1 ) and phyllostine (2 ) were 4.38 and 6.54 μg/larva in the contact toxicity assay. The oviposition deterrent indexes of the two compounds were 100% for phyllostine acetate (1 ) and 28.6% for phyllostine (2 ) at 50 μg cm−2.CONCLUSION Phyllostine acetate and phyllostine show promise as compounds for the control of
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Abstract C(1)‐vinylation of [
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