N. Jayaraman
Professor
Department of Organic Chemistry
Indian Institute of Science
Bangalore 560 012
Tel.: 091 80 2293-2578 (office); 2293-2406 (lab)
Fax: 091 80 2360-0529
E-mail: jayaraman@orgchem.iisc.ernet.i
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Education:

  • M.Sc.: Annamalai University, Chidambaram, 1988
  • Postdoctoral Fellow: University of Birmingham, England (1994 - 1997) and University of California, Los Angeles, USA (1997 - 1999)(Mentor: Professor Sir J.F. Stoddart)

Major research programs of the group are focused in two major areas of chemistry, namely, carbohydrates and dendrimers.  In carbohydrates, on-going research pertains to: (i) develop new synthetic methodologies; (ii) studies of carbohydrate-protein interactions, by involving designed glycolipids; (iii) materials studies of carbohydrates.  In the area of dendrimers, the research activities are based primarily on: (i) poly(ether imine) and (ii) poly(alkyl aryl ether) dendrimers.

            Synthetic modifications to derive new sugars are important in the chemistry of carbohydrates.  The following are important developments arising from interest on synthetic modifications of sugars: (i) new synthetic methods to prepare naturally-occurring and biologically important 2-deoxy sugars; (ii) methods to prepare cyclic and linear 2-deoxy oligosaccharides and (iii) new synthetic methodologies of the ring expansion of oxyglycals, which allows conversion of a pyranoside to a variety seven-membered septanosides.

 

In the area of carbohydrate-protein interactions, the investigations address details of the interactions, the results of which lead to resolving some of the pertinent issues prevailing in this major class of biological interactions.  Primarily, it is established that bivalent cluster glycosides are sufficient to engage in significantly enhanced binding between the sugar ligands and the protein receptors.  Studies on synthetic lipoarabinomannan glycolipids, their activities as inhibitors of mycobacterial growth, as well as, their binding affinities to purified proteins are pursued, in order to understand structures and functions of mycobacterial cell wall polysaccharides, especially, lipoarabinomannans. 

The materials properties of the clustered sugar amphiphiles and glycolipids contribute significantly, primarily in the area of the carbohydrate-based liquid crystals.  The relation between the number of the hydroxyl groups in the sugars and the hydrophobic balances, in order for the mesophase properties to evolve, are continuing theme of research.  These advancements in the sugar based amphiphiles are important, as the studies de-convolute the hydrogen-bonding interactions and the mesophase properties of amphiphilic carbohydrates. 

In the area of the dendrimers, constitutionally new poly(alkyl aryl ether) and poly(ether imine) (PETIM) series of dendrimers are investigated in varied chemical, biological and materials studies

Few relevant publications are given below.  Please click on the topic to go through details of the research activities.

Carbohydrate Chemistry

  • “Synthesis and conformational studies of septanoside containing trisaccharides”, Ganesh, N. V.; Sonti, R.; Raghothama, S.; Jayaraman, N. J. Org. Chem. 2010, 75, 215-218.
  • “Synthesis of 2-deoxy-2-C-alkyl glycal and glycopyranosides from 2-hydroxy glycal ester”, Daskhan, G. C.; Jayaraman, N. J. Org. Chem. 201277, 2185-2191.
  • “2,3-Unsaturated enoses.  A Pummerer rearrangement route to sugar vinyl sulfides and synthesis of 3-deoxy-3-alkyl/arylsulfinylpyranosides”, Mukherjee, A.; Jayaraman, N. Tetrahedron 2012, 68, 8746-8752.
  • “Multivalent ligand presentation as a central concept to study intricate carbohydrate-protein interactions”, Jayaraman, N. Chem. Soc. Rev. 2009, 38, 3463-3483.
  • “Synthesis, biological studies of linear and branched arabinofuranoside-containing glycolipids and their interaction with surfactant protein A”, Naresh, K.; Avaji, P. G.; Bharati, B. K.; Chatterji, D.; Jayaraman, N. Glycobiology 2011, 21,1237-1254.
  • “Role of hydroxyl group on the mesomorphism of alkyl glycosides: Synthesis and thermal behavior of alkyl 6-deoxy-b-D-glucopyranosides”, Singh, M. K.; Jayaraman, N.; Rao, D. S. S.; Prasad, S. K. Chem. Phys. Lipids 2010, 163, 580-585.

Dendrimer Chemistry
  • “Synthesis of multivalent dendritic thiols and formation of dendritic cross-links through thiol-disulfide interchange reaction”, Kiran, B. M.; Jayaraman, N. Macromolecules 2009, 42, 7353-7359.

  • “Increased catalytic efficiencies of multivalent dendritic catalysts.  Synthesis and studies of Rh(I) catalysts within and across poly(alkyl aryl ether) dendrimers” Natarajan, B.; Jayaraman, N. J. Organomet. Chem. 2011, 696, 722-730.
  • “Interfacial regions governing internal cavities of dendrimers.  Studies of poly(alkyl aryl ether) dendrimers constituted with linkers of varying alkyl chain length”, Natarajan, B.; Gupta, S.; Ramamurthy, V.; Jayaraman, N. J. Org. Chem. 2012, 77, 2219-2224.
  • “Inherent photoluminescence properties of poly (propyl ether imine) dendrimers”, Jayamurugan, G.; Umesh, C. P.; Jayaraman, N. Org. Lett. 2008, 10, 9-12.
  • “Dendritic poly (ether imine) based gene delivery vector”, Ullas, P. T.; Madhusudana, S. N.; Desai, A.; Jayamurugan, G.; Rajesh, Y. B. R. D.; Jayaraman, N. Bioconjugate Chem. 2011, 22, 115-119.
  • “Efficacies of multivalent vs monovalent poly (ether imine) dendritic catalysts within a generation in multiple C-C bond forming reactions” Bagul, R. S.; Jayaraman, N. J.Organomet. Chem. 2012, 701, 27-35.