02196nas a2200241   4500008004100000022001400041245015400055210006900209260007700278300001400355490000600369520123800375653002401613653002101637653003201658653002101690653001401711100002801725700002701753700002801780700002001808856012601828       2012                        eng d  a1860-717900aEfficient synthesis of a hydroxyethylamine (HEA) isostere and its alpha-aminophosphonate and phosphoramidate derivatives as potential anti-HIV agents0 aEfficient synthesis of a hydroxyethylamine HEA isostere and its   aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcSEP  a1601-16110 v73 a<p>HIV protease is a promising drug target for AIDS therapy, and several potent HIV-1 protease inhibitors have been reported to date. Although existing inhibitors exhibit high selectivity, they have also been associated with severe side effects and the possible emergence of therapeutic resistance. As HIV protease cleaves the peptide bond via a tetrahedral intermediate, various transition-state models such as hydroxyethylamine (HEA) have been designed. We therefore pursued an efficient synthesis of an HEA isostere; this was performed with a novel one-pot reductiontransiminationreduction reaction sequence as a key step. a-Aminophosphonate and phosphoramidate derivatives of the HEA isostere were designed and synthesized, and all of the synthesized derivatives were assayed for their anti-HIV activities against wild-type and mutant HIV strains. Phosphoramidate derivative 15?a was found to be the most active of all synthesized compounds against the IIIB and RES056 strains. As phosphonates are known to exhibit physiological stability, good cell permeability, and other promising pharmacokinetic characteristics, our newly synthesized compounds have the potential as alternatives to existing therapeutics and diagnostics.</p>10aa-aminophosphonates10aantiviral agents10ahydroxyethylamine isosteres10aphosphoramidates10asynthesis1 aBhattacharya, Asish, K.1 aRana, Kalpeshkumar, C.1 aPannecouque, Christophe1 aDe Clercq, Eric  uhttp://library.ncl.res.in/content/efficient-synthesis-hydroxyethylamine-hea-isostere-and-its-alpha-aminophosphonate-and-001559nas a2200217   4500008004100000022001400041245012200055210006900177260010600246300001400352490000700366520067200373653003301045653001401078653003201092653002301124653002401147100001401171700002801185856012801213       2012                        eng d  a0040-403900aSugar-amino acid cyclic conjugates as novel conformationally constrained hydroxyethylamine transition-state isosteres0 aSugaramino acid cyclic conjugates as novel conformationally cons  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJUN  a3361-33630 v533 a<p>Hydroxyethylamine (HEA) isosteres have previously been shown to display a multitude of biomedical applications. In fact, the first protease inhibitor, saquinavir is an HEA based peptidomimetic. Herein we describe an easy-to-operate synthetic route to a series of carbohydrate-based conformationally constrained hydroxyethylamine (HEA) isosteres featuring amino acid side chains, starting from D-glucose. This class of novel sugar-amino acid-tethered conformationally restricted HEA systems may have bearing in practical application, particularly in the development of conformationally restricted protease inhibitors. (C) 2012 Elsevier Ltd. All rights reserved.</p>10aConformationally constrained10aD-Glucose10ahydroxyethylamine isosteres10aprotease inhibitor10aReductive amination1 aRoy, Arup1 aSanjayan, Gangadhar, J.  uhttp://library.ncl.res.in/content/sugar-amino-acid-cyclic-conjugates-novel-conformationally-constrained-hydroxyethylamine-0