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In our efforts to design mono‐carbonyl analogues of curcumin with potential antiplasmodial activity, diarylidenecyclopentanone (DACP) derivatives, Ia–Iu and II–V, have been synthesized and characterized using 1H NMR, 13C NMR, IR, UV–Vis, and mass spectrometry. Structure of one of these DACPs has been verified by single crystal XRD. At the outset, all 25 DACPs were first screened at 12.5 µM for their in vitro antiplasmodial activity against the chloroquine (CQ)‐sensitive Pf3D7. The three most potent compounds (In, It, and Ik) were further tested at <10 µM concentrations against Pf3D7, PfINDO (CQ resistant), and PfMRA‐1240 (Artemisinin resistant) strains for determination of their IC50s and resistance indices. The drug profile of the DACPs was found to be very promising, with the most active compound It (IC50 1.39 µM against PfINDO) showing a selectivity index of ∼17 tested using HUH‐7 and HEK‐293T mammalian cell lines. Molecular docking studies with Pf pyridoxal synthase showed a good correlation between docking scores of DACPs and in vitro antiplasmodial activity. Further, high conformity with Lipinski's parameters indicates that these DACPs are promising antiplasmodial lead compounds. [ABSTRACT FROM AUTHOR]

Arjunolic acid (AA) is a pentacyclic triterpene acid with various potent biological activities. In this work, arjunolic acid was isolated from the heartwood of Terminalia arjuna, and a series of novel arjunolic acid acetals were synthesized and characterized. The anti-cancer activity of the synthesized acetals was investigated against sixty cell lines from nine different types of cancers at the National Cancer Institute (NCI). Compounds AA-2, AA-4, AA-9, and AA-18 demonstrated significant activity against colon cancer. These compounds were selected for further studies against murine colon cancer cell line CT-26. Mechanistic studies of the most active compound AA-9 on CT-26 cells revealed cell cycle arrest in the G2/M phase, which induces ROS generation in cells, leading to cell death. Additionally, compound AA-9 showed better selectivity for tumour cells and non-tumour cells. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are effective supports for nanometals and together they represent hybrids that combine the unique properties of both. A microwave-induced reaction was used to deposit nanopalladium on carboxylated and octadecylamine functionalized multiwall CNTs, which were used to carry out C–C coupling reactions in dimethylformamide (DMF) and toluene. These hybrids showed excellent catalytic activity with yield as high as 99.8%, while its enhancement with respect to commercially available Pd/C catalyst reached as high as 109%, and the reaction times were significantly lower. The polarity of the functionalized form was found to be a significant factor with the polar carboxylated CNT showing better activity in DMF while the relatively nonpolar octadecyl amine was better in toluene. The results suggest the possibility of tailor making functionalized CNTs when used as catalyst supports.

Twenty-five (Ia–Iu, IIa–IIb, IIIa, and IVa) diarylidene-N-methyl-4-piperidones (DANMPs) were synthesized and characterized via UV, FT-IR, NMR, and MS while Id was characterized also by single crystal XRD. Twenty-one compounds shortlisted after initial in vitro anti-plasmodial activity successive screenings at 100 μM and 10 μM were evaluated for their IC50s against chloroquine-sensitive Pf3D7, chloroquine-resistant PfINDO, and artemisinin-resistant PfMRA-1240 strains. The four most promising compounds were Ie (IC50s μM 0.35MRA, 1.39INDO, 1.923D7), If (IC50s μM 1.07MRA, 1.36INDO, 3.393D7), Ir (IC50s μM 0.74MRA, 2.45INDO, 1.443D7), and In (IC50s μM 1.27MRA, 1.8INDO, 1.73D7). Resistance indices as low as 0.2 to 0.5 for these potent compounds and <1 for most other compounds suggest their greater potency against drug resistant strains than the drug sensitive strain. The parasiticidal action of Ir was seen within 4 h against the trophozoite stage of the parasite, which is known to express the highest levels of PLP synthase. In silico docking scores of −7.0 to −8.0 kcal mol−1 between potent DANMPs and PfPLP synthase, the direct binding of Ir studied by SPR to recombinantly expressed and purified PfPdx-1 and inhibition of Pdx1 enzymatic activity by Ir suggest this vital enzyme to be a probable target for the DANMPs. The non-hemolytic nature of Ir and conformity of most DANMPs to Lipinski's parameters indicate their potential as new anti-plasmodial leads with PfPLP synthase as one of their targets. [ABSTRACT FROM AUTHOR]

This study is the first report on the anticancer activity of spirobibenzopyrans, an unexplored class of therapeutic agents. The synthesized spirobibenzopyrans were tested for anticancer activity across the NCI-60 cell-line panel. The in vitro and in silico results of the spirobibenzopyrans showed tremendous drug likeness scores as potential anticancer agents. [ABSTRACT FROM AUTHOR]