@article { ISI:000297737900020, title = {Synthesis and structural characterization of homochiral homo-oligomers of parent CIS- and trans-furanoid-beta-amino acids}, journal = {Chemistry-A European Journal}, volume = {17}, number = {46}, year = {2011}, month = {NOV}, pages = {12946-12954}, publisher = {WILEY-V C H VERLAG GMBH}, address = {PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY}, abstract = {

The synthesis of homochiral homo-oligomers of cis- and trans-3-aminotetrahydrofuran-2-carboxylic acids (parent cis- and trans-furanoid-beta-amino acids, referred to as {\textquoteleft}{\textquoteleft}cis-/trans-FAA{\textquoteright}{\textquoteright}) has been carried out to understand their secondary structures and their dependence on the ring heteroatom. The oligomers of two diastereomers have been shown to have a distinct left-handed helicity. The cis-FAA homo-oligomers show a 14-helix structure, in contrast to the homo-oligomers of cis-ACPC, which adopt a sheet like structure. The trans-FAA homo-oligomers were found to adopt a 12-helix structure, the same trend found in trans-ACPC homo-oligomers. With the help of ab initio calculations, the structural features of cis-ACPC and cis-FAA hexamers were compared. We believe that the more compact packing of the cis-FAA hexapeptide should be due to a more favorable interaction between the ring and the backbone amide hydrogen.

}, keywords = {ab initio calculations, Amino acids, Density functional calculations, Peptides, secondary structures}, issn = {0947-6539}, doi = {10.1002/chem.201101855}, author = {Pandey, Sunil K. and Jogdand, Ganesh F. and Oliveira, Joao C. A. and Mata, Ricardo A. and Rajamohanan, Pattuparambil R. and Ramana, Chepuri V.} } @article { ISI:000303157400022, title = {Synthesis and structural characterization of homochiral homo-oligomers of cis-gamma-methoxy-substituted cis- and trans-furanoid-beta-amino acids}, journal = {European Journal of Organic Chemistry}, number = {13}, year = {2012}, month = {MAY}, pages = {2656-2663}, publisher = {WILEY-V C H VERLAG GMBH}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, abstract = {

Herein we describe the synthesis of cis-/trans-3-aminotetrahydrofuran-2-carboxylic acids (cis-/trans-FAA) having a ?-methoxy group cis to the amine. The homo-oligomers of these two diastereomeric FAAs have been prepared. Preliminary investigation of their solution secondary structures revealed that they are the same as the homo-oligomers of the parent cis-/trans-FAA with the methoxy group only being a spectator substituent.

}, keywords = {Amino acids, helical structures, Oxygen heterocycles, Peptides}, issn = {1434-193X}, doi = {10.1002/ejoc.201101424}, author = {Giri, Awadut G. and Jogdand, Ganesh F. and Rajamohanan, Pattuparampil R. and Pandey, Sunil K. and Ramana, Chepuri V.} } @article { ISI:000337129000023, title = {Stereoselective approach to indolizidine and pyrrolizidine alkaloids: total synthesis of (-)-lentiginosine, (-)-epi-lentiginosine and (-)-dihydroxypyrrolizidine}, journal = {Organic \& Biomolecular Chemistry}, volume = {12}, number = {25}, year = {2014}, month = {MAY}, pages = {4454-4460}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

A simple and highly efficient approach to hydroxylated pyrrolizidine and indolizidine is developed from an aldehyde as a starting material using organocatalytic and asymmetric dihydroxylation reactions as key steps. Its application to the total synthesis of (-)-lentiginosine, (-)-epi-1,2-lentiginosine and (-)-dihydroxypyrrolizidine is also reported.

}, issn = {1477-0520}, doi = {10.1039/c4ob00461b}, author = {Kauloorkar, Shruti Vandana and Jha, Vishwajeet and Jogdand, Ganesh F. and Kumar, Pradeep} } @article { ISI:000358229500042, title = {Stereocontrolled synthesis of Hagen{\textquoteright}s gland lactones via iterative proline catalyzed alpha-aminoxylation and oxa-Michael addition reactions}, journal = {RSC Advances}, volume = {5}, number = {75}, year = {2015}, month = {JUL}, pages = {61000-61005}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

A simple and efficient synthesis of Hagen{\textquoteright}s gland lactones was achieved using a sequential alpha-aminoxylation/oxa-Michael approach in a highly diastereoselective manner with assignment of relative configurations. This method was found to be applicable to the synthesis of various other isomers of Hagen{\textquoteright}s gland lactones.

}, issn = {2046-2069}, doi = {10.1039/c5ra10082h}, author = {Kauloorkar, Shruti Vandana and Jha, Vishwajeet and Jogdand, Ganesh F. and Kumar, Pradeep} }