Development of 1-(4-(Substituted)piperazin-1-yl)-2-((2-((4-methoxybenzyl)thio)pyrimidin-4-yl)oxy)ethanones That Target Poly (ADP-Ribose) Polymerase in Human Breast Cancer Cells.

A number of uracil amides cleave poly (ADP-ribose) polymerase and therefore novel thiouracil amide compounds were synthesized and screened for the loss of cell viability in a human-estrogen-receptor-positive breast cancer cell line. The synthesized compounds exhibited moderate to significant efficacy against human breast cancer cells, where the compound 5e IC50 value was found to be 18 µM. Thouracil amide compounds 5a and 5e inhibited the catalytical activity of PARP1, enhanced cleavage of PARP1, enhanced phosphorylation of H2AX, and increased CASPASE 3/7 activity. Finally, in silico analysis demonstrated that compound 5e interacted with PARP1. Hence, specific thiouracil amides may serve as new drug-seeds for the development of PARP inhibitors for use in oncology.

Novel 1,3,4-oxadiazole Targets STAT3 Signaling to Induce Antitumor Effect in Lung Cancer.

Lung cancer is the leading type of malignancy in terms of occurrence and mortality in the global context. STAT3 is an oncogenic transcription factor that is persistently activated in many types of human malignancies, including lung cancer. In the present report, new oxadiazole conjugated indazoles were synthesized and examined for their anticancer potential in a panel of cancer cell lines. Among the new compounds, 2-(3-(6-chloro-5-methylpyridin-3-yl)phenyl)-5-(1-methyl-1H-indazol-3-yl)-1,3,4-oxadiazole (CHK9) showed consistently good cytotoxicity towards lung cancer cells with IC50 values ranging between 4.8-5.1 µM. The proapoptotic effect of CHK9 was further demonstrated by Annexin-FITC staining and TUNEL assay. In addition, the effect of CHK9 on the activation of STAT3 in lung cancer cells was examined. CHK9 reduced the phosphorylation of STAT3Y705 in a dose-dependent manner. CHK9 had no effect on the activation and expression of JAK2 and STAT5. It also reduced the STAT3-dependent luciferase reporter gene expression. CHK9 increased the expression of proapoptotic (p53 and Bax) proteins and decreased the expression of the antiapoptotic (Bcl-2, Bcl-xL, BID, and ICAM-1) proteins. CHK9 displayed a significant reduction in the number of tumor nodules in the in vivo lung cancer model with suppression of STAT3 activation in tumor tissues. CHK9 did not show substantial toxicity in the normal murine model. Overall, CHK9 inhibits the growth of lung cancer cells and tumors by interfering with the STAT3 signaling pathway.

Anti-proliferative activity and characterization data on oxadiazole derivatives.

This data in brief article explains the anti-cancer activity and characterization of oxadiazoles [1]. The main objective of this article was to provide general synthetic procedures, spectral discussion and physical data on the new oxadiazole tethered indazole (OTDs). This article discusses the 1H NMR, 13C NMR, mass spectroscopy, HPLC and melting point of the synthetic compounds. MTT assay was used to determine the anti-proliferative activity in hepatocellular cell lines.

Exploring the newer oxadiazoles as real inhibitors of human SIRT2 in hepatocellular cancer cells.

A novel series of indazole tethered oxadiazoles (OTDs) derivatives were synthesized, characterized and screened for their anti-proliferative activity against hepatocellular carcinoma (HCC) cells. OTDs structure was further confirmed by Single-crystal X-ray diffraction studies. Among the tested OTDs, compound 2-(4-methoxyphenyl)-5-(1-methyl-1H-indazol-3-yl)-1,3,4-oxadiazole was found to inhibit the catalytical activity of SIRT2 and brings about apoptosis as shown by western blot analysis and flow cytometry data. Also, the tested OTDs were found to interact with the active site of human SIRT2 in silico but not with the cavity of co-crystal ligand 5-(3- hydroxypropyl)-3-(4-chlorophenyl)-1,2,4-oxadiazole, which indicate that these OTDs has potential in the development of SIRT2 inhibitors in liver cancer models.

Prealamethicin F50 and related peptaibols from Trichoderma arundinaceum: Validation of their authenticity via in situ chemical analysis.

In the field of natural products chemistry, a common question pertains to the authenticity of an isolated compound, i.e. are the interesting side chains biosynthesized naturally or an artefact of the isolation/purification processes? The droplet-liquid microjunction-surface sampling probe (droplet-LMJ-SSP) coupled to a hyphenated system (UPLC-UV-HRESIMS) empowers the analysis of natural product sources in situ, providing data on the biosynthetic timing and spatial distribution of secondary metabolites. In this study the droplet-LMJ-SSP was utilized to validate the authenticity of two new peptaibols (2 and 3) as biosynthesized secondary metabolites, even though both them had structural features that could be perceived as artefacts. Compounds 2 and 3 were isolated from the scaled up fermentation of Trichoderma arundinaceum (strain MSX70741), along with a new member of the trichobrevin BIII complex (1), and four known compounds (4-7). The structures of the isolates were established using a set of spectroscopic and spectrometric methods, and their absolute configurations were determined by Marfey's analysis. The cytotoxic activity of compounds 1, 3, 4 and 6 was evaluated against a panel of cancer cell lines, where cytotoxic activity in the single digit µM range was observed.

MPK-09, a small molecule inspired from bioactive styryllactone restores the wild-type function of mutant p53.

In the search for more efficacious and less toxic cancer drugs, the tumor suppressor p53 protein has long been a desirable therapeutic target. In the recent past, few independent studies have demonstrated that the antitumor activity of wild-type p53 can be restored in cancer cells harboring mutant form of p53 using small molecule activators. In this study, we describe a novel small molecule MPK-09, which is selective and highly potent against allele specific p53 mutations mainly, R175H, R249S, R273H, R273C, and E285K . Except E285K, all other mutations tested are among the six "hot spot" p53 mutations reported in majority of human cancer. Furthermore, our study conclusively demonstrates that the apoptotic activity of the small molecule MPK-09 against cancer cells harboring R273C and E285K mutations is due to restoration of the wild-type conformation to the corresponding mutant form of p53.

Enantiospecific total synthesis of (-)-bengamide E.

Total synthesis of the polyhydroxy caprolactam amide natural product, bengamide E, is accomplished starting from tartaric acid. Key reactions in the synthesis include desymmetrization of the bis(dimethylamide) unit of tartaric acid, Zn(BH(4))(2)-mediated anti-selective reduction, and a Horner-Wadsworth-Emmons olefination.