The ribonucleoside analogues (E)-5-(2-bromovinyl)uridine (5-BV-Urd) and 3´-spiro-(4´-amino-1´,2´-oxathiole-2´,2´-dioxide)-5-methyluridine (3´-AOD-5-MeUrd) emerged as potent and selective competitive inhibitors of mitochondrial thymidine kinase (TK)-2 with respect to thymidine (Ki/Km values of 9.0 and 1.2 respectively). Cytosolic TK-1 did not show measurable affinity for these compounds. [32P]Phosphate transfer studies from [γ-32P]ATP to 5-BV-Urd and 3´-AOD-5-MeUrd revealed extremely poor substrate activity but potent inhibitory potential of the compounds. It was concluded that the ribonucleosides 5-BV-Urd and 3´-AOD-5-MeUrd represent two new lead compounds for potent and selective inhibitors of mitochondrial TK-2.
There are now exactly 20 anti-HIV drugs licenced (approved) for clinical use, and > 30 anti-HIV compounds under (pre)clinical development. The licensed anti-HIV drugs fall into five categories: nucleoside reverse transcriptase inhibitors (NRTIs: zidovudine, didanosine, zalcitabine, stavudine, lamivudine, abacavir and emtricitabine); nucleotide reverse transcriptase inhibitors (NtRTIs: tenofovir disoproxil fumarate); non-nucleoside reverse transcriptase inhibitors (NNRTIs: nevirapine, delavirdine and efavirenz); protease inhibitors (PIs: saquinavir, indinavir, ritonavir, nelfinavir, amprenavir, lopinavir, atazanavir and fosamprenavir); and fusion inhibitors (FIs: enfuvirtide). The compounds that are currently under clinical (Phase I, II or III) or preclinical investigation are either targeted at the same specific viral proteins as the licensed compounds (i.e., reverse transcriptase [NRTIs: PSI-5004, (-)-dOTC, DPC-817, elvucitabine, alovudine, MIV-210, amdoxovir, DOT; NNRTIs: thiocarboxanilide, UC-781, capravirine, dapivirine, etravirine, rilpivirine], protease [PIs: tipranavir, TMC-114]) or other specific viral proteins (i.e., gp120: cyanovirin N; attachment inhibitors: AIs, such as BMS-488043; integrase: L-870,812, PDPV-165; capsid proteins: PA-457, alpha-HCG); or cellular proteins (CD4 downmodulators: CADAs; CXCR4 antagonists: AMD-070, CS-3955; CCR5 antagonists: TAK-220, SCH-D, AK-602, UK-427857). Combination therapy is likely to remain the gold standard for the treatment of AIDS so as to maximise potency, minimise toxicity and diminish the risk for resistance development. Ideally, pill burden should be reduced to once-daily dosing so as to optimise the patient's compliance and reduce the treatment costs.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Le Frittage Selectif par Laser (FSL) est un procede de prototypage rapide prometteur pour la fabrication d'objects 3D fonctionnels par frittage direct de poudres metalliques. Un modele analytique simple a ete developpe pour simuler l'absorption et la penetration de l'energie laser dans le FSL. Ce modele a ete utilise pour des melanges de poudres Fe-Cu et WC-Co, irradiees par lasers Nd-YAG ou CO 2 . Il permet d'evaluer la fraction d'energie totale absorbee et la penetration optique du faisceau laser dans les poudres et de donner une estimation des dimensions de la zone frittee. Les resultats de simulation aideront non seulement a avoir une meilleure connaissance des phenomenes physiques associes mais aussi a optimiser le procede FSL.
