01502nas a2200181   4500008004100000022001400041245014500055210006900200260010600269300001400375490000700389520070700396100002301103700002401126700002401150700002801174856011801202       2008                        eng d  a0040-403900aPre-organization-mediated macrocylization: efficient synthesis and structural investigations of BINOL-m-phenylenediamine-derived macrocycles0 aPreorganizationmediated macrocylization efficient synthesis and   aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcMAR  a2139-21420 v493 a<p>This letter describes a serendipitous discovery of an efficient synthetic route to BINOL-m-phenylenediamine-derived macrocycles. These macrocycles are quickly accessible in an one-pot procedure by the direct condensation of (R) and (S) BINOL bis-acids with suitably substituted m-phenylenediamine analogs. Structural investigations by single crystal X-ray crystallography and solution-state NMR studies provided convincing evidence of their intramolecular hydrogen bonding arrangement and rigid structural architecture. The striking feature of these macrocycles is their ready accessibility in optically pure form coupled with their ease of synthesis. (C) 2008 Elsevier Ltd. All rights reserved.</p>1 aSrinivas, Deekonda1 aGonnade, Rajesh, G.1 aRajamohanan, P., R.1 aSanjayan, Gangadhar, J.  uhttps://library.ncl.res.in/content/pre-organization-mediated-macrocylization-efficient-synthesis-and-structural-001445nas a2200205   4500008004100000022001400041245009200055210006900147260011000216300001600326490000600342520063800348100001400986700002201000700002301022700002601045700002401071700002801095856011601123       2014                        eng d  a2046-206900aProbing the folding induction ability of orthanilic acid in peptides: some observations0 aProbing the folding induction ability of orthanilic acid in pept  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJAN  a13018-130250 v43 a<p>This paper describes the ability of orthanilic acid (2-aminobenzenesulfonic acid, (S)Ant) to promote folding when introduced in a peptide sequence. Three peptide sequences, containing orthanilic acid (SAnt) with a sulfonamide moiety in the turn segment, have been synthesized in the solution phase using suitable coupling agents, and their structural aspects investigated using NMR and X-ray crystallographic studies. Solid- and solution-state conformational analyses reveal that the peptide sequences containing orthanilic acid in their backbone exist in a folded conformation featuring long-range 15-membered ring H-bonding.</p>1 aRoy, Arup1 aKotmale, Amol, S.1 aGawade, Rupesh, L.1 aPuranik, Vedavati, G.1 aRajamohanan, P., R.1 aSanjayan, Gangadhar, J.  uhttps://library.ncl.res.in/content/probing-folding-induction-ability-orthanilic-acid-peptides-some-observations02181nas a2200193   4500008004100000022001400041245010100055210006900156260007100225300001400296490000700310520144300317100002101760700002401781700001501805700002401820700001801844856012501862       2015                        eng d  a0020-166900aPyrazine-based organometallic complex: synthesis, characterization, and supramolecular chemistry0 aPyrazinebased organometallic complex synthesis characterization   a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcMAR  a2543-25500 v543 a<p>The design, synthesis, and characterization of a new pyrazine-based ditopic platinum(II) organometallic complex are reported. The molecular structure of the organoplatinum pyrazine dipod was determined by single-crystal X-ray crystallography. The potential utility of this organometallic ditopic acceptor as a building block in the construction of neutral metallasupramolecular macrocycles containing the pyrazine motif was explored. Pyrazine motifs containing supramolecules were characterized by multinuclear NMR (including H-1 DOSY), mass spectrometry, and elemental analysis. The geometry of each supramolecular framework was optimized by employing the PM6 semi-empirical molecular orbital method to predict its shape and size. The ability of the pyrazine-based organoplatinum complex to act as a host for nitroaromatic guest (2,4-dinitrotoluene and PA) molecules was explored by isothermal titration calorimetry (ITC). The binding stoichiometry and thermodynamic parameters of these host guest complexation reactions were evaluated using ITC. Theoretical calculations were performed to obtain insight into the binding pattern between the organometallic host and nitroaromatic guests. The preferable binding propensity of the binding sites of complex 1 for both nitroaromatics (PA and 2,4-dinitrotoluene) determined by molecular simulation studies corroborates well with the experimental results as obtained by ITC experiments.</p>1 aBhowmick, Sourav1 aChakraborty, Sourav1 aDas, Atanu1 aRajamohanan, P., R.1 aDas, Neeladri  uhttps://library.ncl.res.in/content/pyrazine-based-organometallic-complex-synthesis-characterization-and-supramolecular-0