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A series of chalcones ( 1- 8) were prepared by Claisen-Schmidt condensation of 3-nitroacetophenone with various aldehydes. These chalcones on cyclization with hydrazine hydrate in the presence of glacial acetic acid, hydrazine hydrate in absolute ethanol and ethyl acetoacetate in the presence of barium hydroxide gave corresponding N-acetyl pyrazolines ( 9- 16), N-unsubstituted pyrazolines ( 17- 19) and cyclohexenone derivatives ( 20- 22). All the synthesized compounds were evaluated for their in vitro antibacterial and antifungal activity by using broth microdilution method, and many compounds showed promising activity against various tested bacteria and fungi. Among various tested compounds, 16 and 19 exhibited strongest activities against Streptococcus pyogenes and Pseudomonas aeruginosa; both have MIC value of 25 μg/mL, which is fourfold greater than the standard drug. Many compounds showed good activity against Candida albican. Analogs 11, 12, 15- 17 and 19 displayed two- to fivefold greater activity against C. albican as compared to the standard drug. Results of antitubercular evaluation revealed that compounds 4 and 19 displayed strong antimycobacterial activity against HRv having MIC of 25 and 62.5 μg/mL, respectively. All analogs were found to be inactive against Leishmania braziliensis except analogs 4 and 5 which exhibited strong leishmanicidal activity against Leishmania promastigotes with IC values of 9.3 and 8.9 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of the methanolic extract of Tagetes minuta L. (Asteraceae) leaves resulted in the isolation and identification of two new compounds: 5-methyl-2,2',5',2'',5'',2''',5''',2''''-quinquethiophene (1) and quercetagetin-6-O-(6-Ocaffeoyl- β-D-glucopyranoside) (9), in addition to seven known compounds: quercetin-3,6- dimethyl ether (2), quercetin-3-methyl ether (3), quercetin (4), axillarin-7-O-β-Dglucopyranoside (5), quercetagetin-3,7-dimethoxy-6-O-β-D-glucopyranoside (6), quercetagetin-7-methoxy-6-O-β-D-glucopyranoside (7), and quercetagetin-6-O-β-Dglucopyranoside (8). The compounds were identified by UV, IR, 1D, 2D NMR, and HRESIMS spectral data. They showed significant antioxidant activity, comparable with that of propyl gallate. Compounds 8 and 3 showed weak to moderate antileishmanial and antimalarial activities, with IC50 values of 31.0 μg/mL and 4.37 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A new fatty alcohol ( 1) together with ten known compounds was isolated from the leaves of Terminalia arjuna Roxb. Their chemical structures were established on the basis of physical, chemical, and spectroscopic methods to be identified as ( E)-3,5,7,16 tetramethylheptadeca-2-en-1-ol ( 1), apigenin, luteolin, vitexin, isovitexin, luteolin-3′-glucuronide, gallic acid, methyl gallate, ellagic acid, stigmasterol, and β-sitosterol-3- O-glucoside. Apigenin, vitexin, and isovitexin were isolated for the first time from this species, while luteolin-3′-glucuronide was isolated for the first time from the genus Terminalia. Compound 1 and its acetate derivative ( 2) showed good antileishmanial activity with IC values of 9.0 and 2.0 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Twelve 13-benzyl-15,16-bisnorlabdanes in which the C-13 and C-14 substituents are varied have been prepared from the naturally occurring labdane diterpene (+)-manool. These synthesised compounds were evaluated for antimalarial activity, in vitro as hemozoin formation inhibitors and in vivo against Plasmodium berghei. These derivatives were also assayed for antileishmanial activity against Leishmania mexicana. [ABSTRACT FROM AUTHOR]

Objective: Homalium letestui Pellegr (Flacourtiaceae) is used in traditional medicine in parts of Nigeria for the treatment of malaria, ulcer, and inflammatory diseases and as an aphrodisiac. This investigation was aimed to evaluate the cytotoxic, immunomodulatory, and antileishmanial properties of stem extract and fractions of Homalium letestui (H. letestui). Materials and Methods: Cytotoxic activity against HeLa cells was done using sulphorhodamine (SRB) method and DNA interaction activity using gel electrophoresis. Immunomodulatory activity of the extract in whole blood, neutrophils, and macrophages was also investigated using luminol/lucigenin-based chemiluminescence assay. The extract and fractions were similarly screened for antileishmanial activity against promastigotes of Leishmania major in vitro. The GCMS analysis of the most active fraction against HeLa cells was carried out. Results: The stem extract exerted prominent cytotoxic activity with the dichloromethane fraction exhibiting the most pronounced effect (GI50 -5.12±1.45 µg/ml, LC50-57.3±2.33 µg/ml, TGI -12.6±0.87 µg/ml). The crude extract and the fractions did not interact with DNA when investigated using electrophoresis. The extract significantly ((p<0.05 - 0.001) inhibited oxidative burst activity in whole blood (-27.90-66.90%), isolated polymorphonuclear cells (PMNs) (16.50-67.0%), and mononuclear cells (MNCs) (4.31-98.50%) when two different phagocytosis activators (serum opsonizing zymosan-A and PMA) were used. The extract also exhibited moderate antileishmanial activity against promastigotes of Leishmania major in vitro. GCMS analysis of active fraction revealed pharmacologically active compounds. Conclusion: These results suggest that the stem extract/fractions of H. letestui possess cytotoxic, immunomodulatory, and antileishmanial activities. [ABSTRACT FROM AUTHOR]

In the present report, Nickel oxide nanoparticles (NiONPs) were synthesized using Rhamnus virgata (Roxb.) (Family: Rhamnaceae) as a potential stabilizing, reducing and chelating agent. The formation, morphology, structure and other physicochemical properties of resulting NiONPs were characterized by Ultra violet spectroscopy, X‐ray diffraction (XRD), Fourier Transform Infrared analysis (FTIR), Scanning electron microscopy (SEM), Energy‐dispersive‐spectroscopy (EDS), Transmission electron microscopy (TEM), Raman spectroscopy and dynamic light scattering (DLS). Detailed in vitro biological activities revealed significant therapeutic potential for NiONPs. The antimicrobial efficacy of biogenic NiONPs was demonstrated against five different gram positive and gram negative bacterial strains. Klebsiella pneumoniae and Pseudomonas aeruginosa (MIC: 125 μg/mL) were found to be the least susceptible and Bacillus subtilis (MIC: 31.25 μg/mL) was found to be the most susceptible strain to NiONPs. Biogenic NiONPs were reported to be highly potent against HepG2 cells (IC50: 29.68 μg/ml). Moderate antileishmanial activity against Leishmania tropica (KMH23) promastigotes (IC50: 10.62 μg/ml) and amastigotes (IC50: 27.58 μg/ml) cultures are reported. The cytotoxic activity was studied using brine shrimps and their IC50 value was recorded as 43.73 μg/ml. For toxicological assessment, NiONPs were found compatible towards human RBCs (IC50: > 200 μg/ml) and macrophages (IC50: > 200 μg/ml), deeming particles safe for various applications in nanomedicines. Moderate antioxidant activities: total antioxidant capacity (TAC) (51.43%), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) activity (70.36%) and total reducing power (TRP) (45%) are reported for NiONPs. In addition, protein kinase and alpha amylase inhibition assays were also performed. Our results concluded that Rhamnus virgata synthesized NiONPs could find important biomedical applications with low cytotoxicity to normal cells. [ABSTRACT FROM AUTHOR]

In the present study, plant‐mediated synthesis of iron oxide nanoparticles (IONPs) using leaves extract of Rhamnus virgata (Roxb.) as a potential stabilizing, reducing and chelating agent is reported. The biogenic IONPs are extensively characterized for their physical and biological properties. The morphology, structure and physicochemical properties of biogenic IONPs were characterized using ultraviolet spectroscopy, X‐ray diffraction, Fourier transform‐infrared analysis, scanning electron microscopy, energy‐dispersive spectroscopy, transmission electron microscopy, Raman spectroscopy and dynamic light scattering. The Scherrer equation deduced a mean crystallite size of ~20 nm for IONPs. Detailed in vitro biological activities revealed significant therapeutic potentials for IONPs. Potential antibacterial and antifungal activities are reported for IONPs. Bioinspired IONPs have shown potential results against HepG2 cells (IC50: 13.47 μg/ml). Dose‐dependent cytotoxicity assays were revealed against Leishmania tropica (KMH23) promastigotes (IC50: 8.08 μg/ml) and amastigotes (IC50: 20.82 μg/ml) using different concentrations of IONPs (1–200 μg/ml). The cytotoxic activity was also studied using brine shrimps, and their IC50 value was calculated as 32.41 μg/ml. Significant antioxidant [TAC (51.4%), DPPH (79.4%) and total reducing power (62%)], protein kinase and alpha amylase inhibition assays were revealed. The biocompatibility assays using red blood cells (> 200 μg/ml) and macrophages (> 200 μg/ml) confirmed the biosafe nature of IONPs. In conclusion, bioinspired IONPs have shown potential biological applications and should be subjected to further research work to develop their nano‐pharmacological relevance in biomedical applications. [ABSTRACT FROM AUTHOR]