摘要:
The present process provides an improved method for the preparation of 4-amino-1-((2R,3R,4R,5R)-3-fluoro-4-hydroxy-5-hydroxymethyl-3-methyl-tetrahydrofuran-2-yl)-1H-pyrimidin-2-one of the formula (IV) which is a potent inhibitor of Hepatitis C Virus (HCV) NS5B polymerase.
摘要:
The present process provides an improved method for converting 2′-deoxy-2′-fluoro-2′-methyl-D-ribonolactones derivatives to 3-fluoro-3-methyl-2-chlorofuran compounds which are useful for the synthesis of nucleosides and improved processes for the synthesis of the D-ribonolactone compounds.
摘要:
The present process provides an improved method for the preparation of 4-amino-1-((2R,3R,4R,5R)-3-fluoro-4-hydroxy-5-hydrox-ymethyl-3-methyl-tetrahydro-furan-2-yl)-1H-pyrimidin-2-one of the formula (IV) which is a potent inhibitor of Hepatitis C Virus (HCV) NS5B polymerase.
摘要:
The present process provides a improved method for the preparation of alkylsulfanyl substituted triazoles 2 which are useful intermediates in a new process for the preparation of triazolones 20.
摘要:
The present process provides a improved method for the preparation of alkylsulfanyl substituted triazoles 2 which are useful intermediates in a new process for the preparation of triazolones 20.
摘要:
A process for the preparation of a 4′-azido-2′,3′,5′-triacyl-nucleoside compound (I; B=B1; R1 is R1aCO— and R2 is R2aCO—) or a 4′-azidonucleoside compounds (I; B is B1 or B2 and R1 and R2 are hydrogen and acid addition salts thereof) wherein R1a and R2a are independently C1-10 alkyl or phenyl optionally substituted with 1 to 3 substituents selected from the group consisting of alkyl, alkoxy, halogen, nitro or cyano and R3 is selected from the group consisting of hydrogen, C1-6 alkyl, C1-3 haloalkyl and halogen, comprising contacting a 5′-iodo compound II with a peracid, R2aC(O)OOH, an acid R2aC(O)OH and a phase transfer catalyst and interconverting a uridine B1 to a cytosine B2. The present process provides the 4′-azidonucleosides safely and selectively in high purity with increased efficiency.
摘要:
Manganese coordination complexes with utility as magnetic resonance probes and as biological reductant sensors are disclosed. In one embodiment, ligands can stabilize both the Mn2+ and Mn3+ oxidation states. In the presence of a reductant such as glutathione, low relaxivity MnIII-HBET is rapidly converted to high relaxivity MnII-HBET with a 3-fold increase in relaxivity, and concomitant increase in magnetic resonance signal. In another embodiment, ligands were designed to chelate Mn(ll) in a thermodynamically stable and kinetically inert fashion while allowing for direct interaction of Mn(ll) with water. In yet another embodiment, high molecular weight multimers containing six Mn(ll) chelators were prepared. The high molecular weight results in slower tumbling of the molecules in solution and can strongly enhance the Mn(ll) relaxivity.
摘要:
Electronic devices may be provided with antenna structures. The antenna structures may be used in wirelessly transmitting and receiving radio-frequency signals. Antenna structures may be formed from molded dielectric substrates. Patterned conductive material may be formed on the dielectric substrates. The dielectric substrates may be formed from molded materials such as glass or ceramic. Sheets of dielectric or dielectric powder may be compressed to form a dielectric substrate of a desired shape. The patterned conductive material may be formed from metallic paint or other conductors. A hollow antenna chamber may be formed by joining molded dielectric structures. An antenna such as an indirectly-fed loop antenna or other antennas may be formed from the molded dielectric substrates and patterned conductors.
摘要:
A display cover layer may be mounted in an electronic device housing using housing structures such as corner brackets. A slot antenna may be formed from a corner bracket opening, metal traces on a hollow plastic support structure, or other conductive structures. The slot antenna may have a main portion with opposing ends. An antenna feed may be located at one of the ends. The slot antenna may have a slot with one or more bends. The bends may provide the slot antenna with a C-shaped outline. A side branch slot may extend from the main portion of the slot at a location between the two bends. The presence of the side branch slot may enhance antenna bandwidth. A hollow enclosure may serve as an antenna support structure and as a speaker box enclosing a speaker driver. The antenna feed may be positioned so as to overlap the speaker driver.
摘要:
A statistical transition map is built based on mobile wireless device user mobility history data. This data is useful to assist various wireless local area network applications. Received signal strength and location trace information associated with movements of mobile wireless devices in a wireless network is collected. The received signal strength and location trace information is converted to a sequence of natural language pseudo-location word labels representing pseudo-locations of each mobile wireless device as each mobile wireless device moves about with respect to a plurality of wireless access point devices in the wireless network. A statistical transition map is generated for each mobile wireless device from the sequence of natural language pseudo-location word labels using a natural language model. A probability of a next pseudo-location for a particular mobile wireless device is computed based on its current location and its statistical transition map.