K. M. Muraleedharan

Bio: K. M. Muraleedharan is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Artemisinin & Carboxylic acid. The author has an hindex of 12, co-authored 47 publications receiving 751 citations. Previous affiliations of K. M. Muraleedharan include University of Mississippi & Indian Institute of Chemical Technology.

Sulfamide-Lattice Restructuring To Form Dimensionally Controlled Molecular Arrays and Gel-Forming Systems

Abstract: A design approach that incorporates structural requirements for the formation of a 1D assembly, fibril stability, and fibril-fibril interactions for gelation was attempted by using amino acid-based sulfamides with the general structure Aa-NH-SO2 -NH-Aa (Aa=amino acid). A preference for 1D assembly alone was not a sufficient condition for gelation, which became evident from studies involving sulfamide esters 1-5. Reducing the crystallization tendency without hindering unidirectional growth was executed through diacids of the sulfamide precursors with various amines that form an envelope around the sulfamide core through salt bridges. This strategy was fruitful, and gels of a wide variety of solvents could be formed by varying the acid and amine components. The use of dodecylamine or benzylamine, which could stabilize the molecular layers through alkyl-chain segregation or π-π interactions improved the gelation tendency, whereas the nature of the amino acid side chain, especially the rotational freedom and hydrophobicity, had a direct role in dictating the solvent preference. Crystallographic studies of these two-component systems gave molecular-level insight into the assembly and showed the importance of anisotropy in the distribution of secondary interactions in gelation.

Oxanorbornane-based amphiphilic systems: design, synthesis and material properties

Abstract: The use of oxanorbornane-based sugar-like surfaces in the development of new amphiphilic systems is demonstrated. Crystallographic analysis and results from aggregation studies showed their close resemblance to glycolipids.

Can Helical Peptides Unwind One Turn at a Time? ‐ Controlled Conformational Transitions in α,β2,3‐Hybrid Peptides

Abstract: Unfolding of helical trans-β(2,3) -hybrid peptides with (α-β)n α composition, when executed by increasing solvent polarity or temperature, proceeded in a systematic manner with the turns unwinding sequentially; C-terminal region of these peptides were first to unwind and the process propagated towards N terminus with more and more β residues equilibrating from the gauche to the anti rotameric state across Cα-Cβ . This is evidenced by clear change in their Cβ H signal splitting, (3)JCαH-CβH values, and sequential disappearance of i,i+2 NOEs.

An Expeditious and Metal‐Free Synthetic Route towards Quinolones, Naphthyridones and Benzonaphthyridones

Abstract: An efficient, two-step synthetic strategy has been developed to access the quinolone, naphthyridone and benzonaphthyridone classes of chemotherapeutic agents from Baylis–Hillman adducts. The method involves tandem aza-Michael addition, SNAr cyclisation followed by oxidation of the resulting 4hydroxy-1,2,3,4-tetrahydroquinoline or 4-hydroxy1,2,3,4-tetrahydro-1,8-naphthyridine derivative using IBX, and works well with substrates having a wide variety of substitution pattern.

Peptide-based stimuli-responsive biomaterials

Abstract: This article explores recent advances in the design and engineering of materials wholly or principally constructed from peptides. We focus on materials that are able to respond to changes in their environment (pH, ionic strength, temperature, light, oxidation/reduction state, presence of small molecules or the catalytic activity of enzymes) by altering their macromolecular structure. Such peptide-based responsive biomaterials have exciting prospects for a variety of biomedical and bionanotechnology applications in drug delivery, bio-sensing and regenerative medicine.

Enantioselective bromolactonization of conjugated (Z)-enynes.

Abstract: A catalytic enantioselective syn-1,4-bromolactonization of conjugated (Z)-enynes was reported. Diastereomeric ratios >20:1 and up to 99% enantiomeric excesses were observed. Di-, tri-, and tetra-substituted bromoallenes were prepared together with lactone heterocycles efficiently and stereoselectively. Preliminary investigations suggest that the chiral catalyst may serve as a bifunctional reagent by interacting with both a carboxylic acid nucleophile and NBS electrophile.