01577nas a2200241   4500008004100000022001400041245012300055210006900178260010600247300001400353490000700367520063200374653001401006653002201020653002001042653002201062100002401084700003001108700001901138700002401157700002501181856012901206       2006                        eng d  a0040-402000aNovel series of oligomers from 4-aminomethyl-tetrahydrofuran-2-carboxylates with 2,4-cis and 2,4-trans stereochemistry0 aNovel series of oligomers from 4aminomethyltetrahydrofuran2carbo  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcAUG  a7718-77250 v623 a<p>Two tetrahydrofuran-based y-amino acids [2,4-cis and 2,4-trans] were subjected to iterative peptide-coupling procedures to afford dimeric, tetrameric and hexameric carbopeptoids in good yield. These homooligomers were prepared for secondary structural study-to ascertain the conformational preference inherent in the monomer units. The L-xylo oligomers were protected with triethylsilyl ethers to increase the range of solvents suitable for structural investigation. Initial secondary structure data indicate the presence of hydrogen-bonded conformations in the L-ribo series. (c) 2006 Elsevier Ltd. All rights reserved.</p>10aFoldamers10agamma amino acids10aPeptidomimetics10asugar amino acids1 aEdwards, Alison, A.1 aSanjayan, Gangadharar, J.1 aHachisu, Shuji1 aTranter, George, E.1 aFleet, George, W. J.  uhttps://library.ncl.res.in/content/novel-series-oligomers-4-aminomethyl-tetrahydrofuran-2-carboxylates-24-cis-and-24-trans-101764nas a2200265   4500008004100000022001400041245010300055210006900158260010600227300001400333490000700347520077400354653002201128653002001150653001401170653002201184100002401206700002801230700001901258700002001277700002201297700002401319700002501343856013001368       2006                        eng d  a0040-402000aSynthesis of 4-aminomethyl-tetrahydrofuran-2-carboxylates with 2,4-cis and 2,4-trans relationships0 aSynthesis of 4aminomethyltetrahydrofuran2carboxylates with 24cis  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcAPR  a4110-41190 v623 a<p>Templated tetrahydrofuran-based gamma-azido esters were prepared with the C-2 and C-4 functionalities in cis and trans relative configurations. This was achieved by ring contraction of the suitably protected 2-O-triflates of pentono-1,5-lactones (D-ribose and L-arabinose) with subsequent introduction of the azide via the 4-O-triflate. Access to a corresponding beta-azido ester was achieved in good yield. Little elimination product was observed by introduction of the azide via the 3-O-triflate. These azido esters are scaffolds. which may be predisposed to adopt secondary structural motifs, for example. for use as peptidomimetics; they may also be utilised for the preparation of stereodiverse compound libraries. (c) 2006 Elsevier Ltd All rights reserved.</p>10agamma amino acids10aPeptidomimetics10ascaffolds10asugar amino acids1 aEdwards, Alison, A.1 aSanjayan, Gangadhar, J.1 aHachisu, Shuji1 aSoengas, Raquel1 aStewart, Alistair1 aTranter, George, E.1 aFleet, George, W. J.  uhttps://library.ncl.res.in/content/synthesis-4-aminomethyl-tetrahydrofuran-2-carboxylates-24-cis-and-24-trans-relationships-0