Reconstructing the absolute chronology of Jerusalem during the time it served as the Judahite Kingdom's capital is challenging due to its dense, still inhabited urban nature and the plateau shape of the radiocarbon calibration curve during part of this period. We present 103 radiocarbon dates from reliable archaeological contexts in five excavation areas of Iron Age Jerusalem, which tie between archaeology and biblical history. We exploit Jerusalem's rich past, including textual evidence and vast archaeological remains, to overcome difficult problems in radiocarbon dating, including establishing a detailed chronology within the long-calibrated ranges of the Hallstatt Plateau and recognizing short-lived regional offsets in atmospheric C concentrations.
View Article and Find Full Text PDFIn the last 50 years, nucleoside analogs have been introduced to drug therapy as antivirals for different types of cancer due to their interference in cellular proliferation. Among the first line of nucleoside treatment drugs, ribavirin (RBV) is a synthetic N-nucleoside with a 1,2,4-triazole moiety that acts as a broad-spectrum antiviral. It is on the World Health Organization (WHO) list of essential medicines.
View Article and Find Full Text PDFThe search for broad-spectrum antiviral compounds is a continuous mandatory effort. The recent approval of the first -nucleoside carrying a nitrile as a substituent at the C1' position of the ribose ring has raised interest in this underexplored substitution pattern. We have previously reported the development of different 1,2,3-triazolyl--ribonucleosides with anticancer and antiviral activities.
View Article and Find Full Text PDFRibavirin is an unnatural nucleoside exhibiting broad spectrum of antiviral and antitumor activities, still very widely studied particularly in a repositioning approach. C-triazolyl nucleoside analogues of ribavirin have been synthesized, as well as prodrugs and glycosylated or peptide conjugates to allow a better activity by vectorization into the liver or by facilitating uptake into the cells. The antiviral properties of all synthesized compounds have been evaluated in vitro against two important human viral pathogens belonging to the Flaviviridae family: hepatitis C virus (HCV) and Zika virus (ZIKV).
View Article and Find Full Text PDFThe article presents results of residue analysis, based on Gas Chromatograph Mass Spectrometer (GC-MS) measurements, conducted on 13 ceramic storage jars unearthed in the Babylonian destruction layer (586 BCE) in Jerusalem. Five of the jars bear rosette stamp impressions on their handles, indicating that their content was related to the kingdom of Judah's royal economy. The identification of the original contents remains is significant for the understanding of many aspects related to the nutrition, economy and international trade in the ancient Levant.
View Article and Find Full Text PDFPhosphoramidates obtained according to the ProTide strategy are known for their ability to increase the biological activity of various nucleosides. A series of such prodrugs of SRO-91, a non-natural ribofuranosyl-1,2,3-triazole C-nucleoside obtained by a synthetic sequence involving an indium mediated alkynylation and a Huisgen cycloaddition, was prepared and the antitumor activity on 3 strains of tumor cells was investigated. Two compounds 9a and 9c exhibited interesting cell proliferative inhibitions (IC = 2.
View Article and Find Full Text PDFRadiocarbon dating is rarely applied in Classical and Post-Classical periods in the Eastern Mediterranean, as it is not considered precise enough to solve specific chronological questions, often causing the attribution of historic monuments to be based on circumstantial evidence. This research, applied in Jerusalem, presents a novel approach to solve this problem. Integrating fieldwork, stratigraphy, and microarchaeology analyses with intense radiocarbon dating of charred remains in building materials beneath Wilson's Arch, we absolutely dated monumental structures to very narrow windows of time-even to specific rulers.
View Article and Find Full Text PDFSRO-91 is a non-natural ribofuranosyl-1,2,3-triazole C-nucleoside obtained by a synthetic sequence involving a C-alkynyl glycosylation mediated by metallic indium and a Huisgen cycloaddition for the construction of the triazole. Its structure is close to the one of ribavirin, a drug presenting a broad-spectrum against viral infections. SRO-91 antitumor activities were investigated on 9 strains of tumor cells and IC of the order of 1 μM were obtained on A431 epidermoid carcinoma cells and B16F10 skin melanoma cells.
View Article and Find Full Text PDFEpithelial ovarian cancers are insidious pathologies that give a poor prognosis due to their late discovery and the increasing emergence of chemoresistance. Development of small pharmacological anticancer molecules remains a major challenge. Ribavirin, usually used in the treatment of hepatitis C virus infections and more recently few cancers, has been a suggestion.
View Article and Find Full Text PDFDirected palladium-catalyzed C-H functionalisation of C2-amido glycals onto the anomeric position is described as a novel route to C-aryl/alkenylglycosides. An aminoquinoline-type directing group was used to successfully introduce diverse (hetero)aryl and alkenyl groups at position 1 of the sugar (20 examples). Its application to the synthesis of a dapagliflozin analogue is presented.
View Article and Find Full Text PDFBiochim Biophys Acta Biomembr
January 2019
Over the past decades, membranotropic peptides such as positively charged cell-penetrating peptides (CPPs) or amphipathic antimicrobial peptides (AMPs) have received increasing interest in order to improve therapeutic agent cellular uptake. As far as we are concerned, we were interested in studying HCV fusion peptides as putative anchors. Two peptides, HCV6 and HCV7, were identified and conjugated to a fluorescent tag NBD and tested for their interaction with liposomes as model membranes.
View Article and Find Full Text PDFThe synthesis of four C-pyrimidyl nucleosides is described by condensation of small nitrogen molecules (amidines and ureas) onto alkynyl riboside derivatives. These last compounds were obtained by indium mediated stereoselective alkynylation of suitably protected ribose derivatives and the condensation reaction conditions were studied in order to favor the N-attack of the nitrogen molecules leading to the pyrimidine ring formation.
View Article and Find Full Text PDFAn efficient synthetic pathway leading to two carbonated analogues of ribavirin is described. The key-steps in the synthesis of these ribosyltriazoles bearing a quaternary carbon atom in the 2'-position are an indium-mediated alkynylation and a 1,3-dipolar cyclization.
View Article and Find Full Text PDFC-Nucleosides are an underexplored and important class of nucleosides with antiviral and anticancer activity. In addition, triazole heterocycles are well employed as a strategy to modify nucleobase in nucleoside analogues, although rare examples were described for triazoyl C-nucleosides. N(2)-Aryl-1,2,3-triazole C-nucleoside compounds that could be obtained by selective 1,2,3-triazole heterocycle N(2) arylation in 1-β-d-ribofuranosyl-2H-1,2,3-triazole substrate were designed in this study.
View Article and Find Full Text PDFGreen glycosylation of functionalized alcohols and α-amino acids, using an ionic liquid as a recyclable solvent, was performed in one step directly from the unprotected monosaccharide under scandium triflate or ferric chloride catalysis. Pure α- and β-glycosides could be obtained after specific enzymatic hydrolysis.
View Article and Find Full Text PDFThe coupling of glycals with an alkynyl iodide bearing a protected amino alcohol moiety was achieved in the presence of metallic indium under Barbier conditions. It gave functionalized C-glycosyl compounds, precursors of C-glycosyl amino acids with α configuration.
View Article and Find Full Text PDFWe report the design, synthesis, and immunological evaluation of a series of glycopeptide analogues of the previously described antigenic probe CSF114(Glc), with the aim of understanding the importance of N-glycosylation on Asn residue in multiple sclerosis antibody recognition. The glucopeptide, characterized by a β-turn conformation which is fundamental for a correct presentation of the epitope, has been modified by introducing various natural glycoamino acids in position 7. The new glycopeptides were evaluated by measuring the IgG and IgM antibody titer in multiple sclerosis patients' and normal blood donors' sera.
View Article and Find Full Text PDFCarbonated analogues of ribavirin were synthesized from ethyl C-ribosylpropiolate obtained by an alkynylation reaction mediated by indium(0). The C-ribosides were then engaged in a Huisgen 1,3-dipolar cycloaddition reaction under a micellar catalysis. In these conditions, formation of 1,2,3-triazoles with control of the regioselectivity was observed.
View Article and Find Full Text PDFIndium-mediated alkynylation reaction was studied for the direct preparation of C-glycosides. Easily available starting sugar derivatives with an acetyl group at the anomeric position were tested as electrophiles toward alkynylindium reagents under Barbier conditions. Good yields and stereoselectivities were observed during the reaction.
View Article and Find Full Text PDFAn efficient Ferrier-type alkynylation reaction between glycals and iodoalkynes using Barbier conditions is described. These conditions require In0, InI, or InII and lead to alpha-2,3-unsaturated-C-glycosides with good stereoselectivity. When glycosyliodoalkynes are used, trehalose-derived compounds and alpha-(1-->6)-C-disaccharides are obtained.
View Article and Find Full Text PDFCyclotetrapeptides are constrained cyclic peptides whose synthesis is considered a difficult task. A methodology based on on-resin head-to-tail cyclization by anchoring the side chain of a trifunctional amino acid was investigated. A series of model cyclotetrapeptides containing the RGD sequence cyclo(Xaa-Arg-Gly-Asp) (Xaa = Ala, Phe, Phg, D-Ala, D-Phe, D-Phg) was synthesized with no cyclodimerization by-products.
View Article and Find Full Text PDFOlefin oxidation with molecular oxygen, promoted by a transition metal catalyst and a thiophenol, involved C=C bond cleavage into the corresponding carbonyl derivatives. This new reaction proceeds under one atmosphere of oxygen, at room temperature, in the presence of an excess of thiophenol and a catalyst such as MnL(2) 3a or VClL(2) 3c. It was applied to aromatic and aliphatic olefins, as well as to functionalized or unfunctionalized acyclic compounds, providing the corresponding ketones and aldehydes in up to 98% yield.
View Article and Find Full Text PDFRats exposed on their first postnatal day to 100% nitrogen for 25 min developed hyperactivity and lower performance in passive avoidance task during development. Administration of MK-801 (0.5 mg/kg i.
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