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Bicyclic amino acid-carbohydrate-conjugates as conformationally restricted hydroxyethylamine (HEA) transition-state
Sangram S Kale1, Sanjay T Chavan, Sushma G Sabharwal
1Division of Organic Chemistry, National Chemical Laboratory, Dr Homi Bhabha Road, Pune, 411 008, India.
Abstract:
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 α-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.
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