22 research outputs found
ChemInform Abstract: Synthesis of a Novel UDP-Carbasugar as UDP-Galactopyranose Mutase Inhibitor.
ChemInform Abstract: The Synthesis of Carbasugars via Ring-Closing Metathesis Applied to the Inhibition of M. Tuberculosis Cell Wall Biosynthesis
Antennas and RF Front Ends for Cognitive Radio
http://www.hindawi.com/journals/ijap/2014/231027/International audienc
Cognitive Radio Transceivers: RF, Spectrum Sensing, and Learning Algorithms Review
A cognitive transceiver is required to opportunistically use vacant spectrum resources licensed to primary users. Thus, it relies on a complete adaptive behavior composed of:
reconfigurable radio frequency (RF) parts, enhanced spectrum sensing algorithms, and sophisticated machine learning techniques. In this paper, we present a review of the recent advances in CR transceivers hardware design and algorithms. For the RF part, three types of antennas are presented: UWB antennas, frequency-reconfigurable/tunable antennas, and UWB antennas with reconfigurable band notches. The main challenges faced by the design of the other RF blocks are also discussed. Sophisticated spectrum sensing algorithms that overcome main sensing challenges such as model uncertainty, hardware impairments, and wideband sensing are highlighted. The cognitive engine features are discussed. Moreover, we study unsupervised classification algorithms and a reinforcement learning (RL) algorithm that has been proposed to perform decision-making in CR networks
A simple synthesis of D-Galactono-1,4-lactone and key building-blocks for the preparation of galactofuranosides
Synthesis of a Novel UDP-carbasugar as UDP-galactopyranose Mutase Inhibitor
The
multistep synthesis of a novel UDP-<i>C</i>-cyclohexene,
designed as a high energy intermediate analogue of the UDP-galactopyranose
mutase (UGM) catalyzed isomerization reaction, is reported. The synthesis
of the central carbasugar involved the preparation of a galactitol
derivative bearing two olefins necessary for the construction of the
cyclohexene ring by a ring-closing metathesis as a key step. Further
successive phosphonylation, deprotection, and UMP coupling provided
the target molecule. The final molecule was assayed against UGM and
compared with UDP-<i>C</i>-Gal<i>f</i>, the C-glycosidic
UGM substrate analogue