01559nas a2200193 4500008004100000022001400041245013000055210006900185260011000254300001400364490000600378520072500384100002201109700002301131700002601154700002601180700002801206856013101234 2011 eng d a1477-052000aBicyclic amino acid-carbohydrate-conjugates as conformationally restricted hydroxyethylamine (HEA) transition-state isosteres0 aBicyclic amino acidcarbohydrateconjugates as conformationally re aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcSEP a7300-73020 v93 a

This communication describes a general synthetic route to bicyclic amino acid-carbohydrate-conjugates, which would be useful as conformationally restricted hydroxyethylamine (HEA) transition-state isosteres. The synthesis was achieved in 12 steps starting from D-glucose. The striking features of this system are the bicyclic rigid core displaying an a-amino acid side chain and hydroxyethylamine moiety - both of which would be potentially important for receptor interactions, leading to various biomedical responses, as described in the literature. Crystal structure investigation suggested extensive intermolecular hydrogen-bonding interactions in this system, involving the backbone amide and hydroxyl groups.

1 aKale, Sangram, S.1 aChavan, Sanjay, T.1 aSabharwal, Sushma, G.1 aPuranik, Vedavati, G.1 aSanjayan, Gangadhar, J. uhttps://library.ncl.res.in/content/bicyclic-amino-acid-carbohydrate-conjugates-conformationally-restricted-hydroxyethylamine-002862nas a2200205 4500008004100000245017400041210006900215260000800284300001200292490000700304520205400311100001702365700002502382700001902407700002502426700002202451700002802473700002402501856013102525 2024 eng d00aBlock copolymer self-assembly: exploitation of hydrogen bonding for nanoparticle morphology control via incorporation of triazine based comonomers by RAFT polymerization0 aBlock copolymer selfassembly exploitation of hydrogen bonding fo cOCT a24011290 v203 a

Synthesis of polymeric nanoparticles of controlled non-spherical morphology is of profound interest for a wide variety of potential applications. Self-assembly of amphiphilic diblock copolymers is an attractive bottom-up approach to prepare such nanoparticles. In the present work, RAFT polymerization is employed to synthesize a variety of poly(N,N-dimethylacrylamide)-b-poly[butyl acrylate-stat-GCB] copolymers, where GCB represents vinyl monomer containing triazine based Janus guanine-cytosine nucleobase motifs featuring multiple hydrogen bonding arrays. Hydrogen bonding between the hydrophobic blocks exert significant influence on the morphology of the resulting nanoparticles self-assembled in water. The Janus feature of the GCB moieties makes it possible to use a single polymer type in self-assembly, unlike previous work exploiting, e.g., thymine-containing polymer and adenine-containing polymer. Moreover, the strength of the hydrogen bonding interactions enables use of a low molar fraction of GCB units, thereby rendering it possible to use the present approach for copolymers based on common vinyl monomers for the development of advanced nanomaterials.

1 aHaque, Farah1 aThompson, Steven, W.1 aIshizuka, Fumi1 aKuchel, Rhiannon, P.1 aSingh, Dharmendra1 aSanjayan, Gangadhar, J.1 aZetterlund, Per, B. uhttps://library.ncl.res.in/content/block-copolymer-self-assembly-exploitation-hydrogen-bonding-nanoparticle-morphology-control