01663nas a2200205   4500008004100000022001400041245011100055210006900166260007100235300001400306490000700320520086900327100002001196700001901216700002401235700002601259700002501285700002401310856012301334       2008                        eng d  a0022-326300aFerrocene-linked thymine/uracil conjugates: base pairing directed self-assembly and supramolecular packing0 aFerrocenelinked thymineuracil conjugates base pairing directed s  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcFEB  a1508-15150 v733 a<p>Ferrocene-linked bis(nucleobase) (la-c) and chimeric nucleobase (1d) conjugates have been synthesized from mono- and bis(hydroxybutyl)ferrocene 6 via Mitsunobu reaction as the key step. X-ray crystallographic studies of ferrocene bis(nucleobase) conjugates reveal two-dimensional supramolecular organizations of backbones through self-assembled Watson-Crick and reverse Watson-Crick type pairs. Ferrocene-bis(thymine) conjugate self-assembles by reverse Watson-Crick pairing, while the corresponding bis(uracil) conjugate self-assembles by alternating WC and reverse WC type pairing. Such continuous assemblies are not seen in monosubstituted ferrocene nucleobase conjugates which form only planar sheets. The results are interesting from the point of understanding and engineering supramolecular assemblies through rational design of base pairing patterns.</p>1 aPatwa, Amit, N.1 aGupta, Susmita1 aGonnade, Rajesh, G.1 aKumar, Vaijayanti, A.1 aBhadbhade, Mohan, M.1 aGanesh, Krishna, N.  uhttps://library.ncl.res.in/content/ferrocene-linked-thymineuracil-conjugates-base-pairing-directed-self-assembly-and-001017nas a2200181   4500008004100000022001400041245008800055210006900143260011000212300001400322520025200336100002300588700002400611700003500635700002400670700002800694856011300722       2008                        eng d  a1359-734500aFoldamers with unusual structural architecture from spirobi(indane) building blocks0 aFoldamers with unusual structural architecture from spirobiindan  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUN  a2541-25433 a<p>This communication demonstrates the utility of inherently rigid building blocks such as 1,1'-spirobi(indane) for generating conformationally ordered synthetic oligomers with structural architectures distinct from those classically observed.</p>1 aKendhale, Amol, M.1 aGonnade, Rajesh, G.1 aRajamohanan, Pattuparambil, R.1 aHofmann, Hans-Joerg1 aSanjayan, Gangadhar, J.  uhttps://library.ncl.res.in/content/foldamers-unusual-structural-architecture-spirobiindane-building-blocks-001159nas a2200193   4500008004100000022001400041245012700055210006900182260007100251300001400322490000700336520037100343100002000714700002400734700002600758700002500784700002400809856013200833       2010                        eng d  a0022-326300aFerrocene-Bis(thymine/uracil) conjugates: base pairing directed, spacer dependent self-assembly and supramolecular packing0 aFerroceneBisthymineuracil conjugates base pairing directed space  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcDEC  a8705-87080 v753 a<p>X-ray crystallographic studies of methylene linked Ferrocene-bis(thymine/uracil) conjugates Fc(T:T)m and Fc(U:U)(M) reveal base dependent 2-D supramolecular assemblies generated via wobble self-pairing for bis-thymine and reverse wobble self-pairing for bis-uracil conjugates, differing in architecture from the corresponding butylene spacer linked conjugates</p>1 aPatwa, Amit, N.1 aGonnade, Rajesh, G.1 aKumar, Vaijayanti, A.1 aBhadbhade, Mohan, M.1 aGanesh, Krishna, N.  uhttps://library.ncl.res.in/content/ferrocene-bisthymineuracil-conjugates-base-pairing-directed-spacer-dependent-self-assembly-001104nas a2200205   4500008004100000022001400041245009200055210006900147260000800216300001600224490000700240520042300247100001500670700001800685700001900703700002400722700002500746700001700771856011000788       2015                        eng d  a1359-734500aFluorescent probe for specific detection of cysteine in the lipid dense region of cells0 aFluorescent probe for specific detection of cysteine in the lipi  cSEP  a16932-169350 v513 a<p>A new cysteine (Cys) specific chemodosimetric reagent (ER-F) is used in imaging of endogenous Cys localized in the lipid dense region of the live Hct116 cells and the release of Cys within HepG2 cells from a drug following a biochemical transformation. A silica surface, modified with ER-F, could be used for quantitative estimation of Cys present in aqueous solution (pH 7.2) and in a human blood plasma (HBP).</p>1 aAli, Firoj1 aAnila, H., A.1 aTaye, Nandaraj1 aGonnade, Rajesh, G.1 aChattopadhyay, Samit1 aDas, Amitava  uhttps://library.ncl.res.in/content/fluorescent-probe-specific-detection-cysteine-lipid-dense-region-cells02858nas a2200217   4500008004100000022001400041245009400055210006900149260007100218300001400289490000700303520205200310100001902362700002402381700002502405700002302430700001902453700002502472700002402497856011902521       2015                        eng d  a1528-748300aFurosemide cocrystals with pyridines: an interesting case of color cocrystal polymorphism0 aFurosemide cocrystals with pyridines an interesting case of colo  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcDEC  a5858-58720 v153 a<p>Furosemide (FS), a loop diuretic drug commonly used for the treatment of hypertension and edema, exhibited color cocrystal polymorphism with coformer 4,4'-bipyridine (4BPY) in the stoichiometry 2:1, albeit both the API and the cocrystal former are colorless. Crystallization from ethanol, isopropanol, ethanol-water (v/v, 1/1) mixture, and acetonitrile yielded pale yellow (form II, thin needles) and orange (form 1II, blocks) cocrystals concomitantly. Needles appeared from solution within a day, while the blocks were obtained after 1-2 days from the same flask, indicating that yellow needles were formed faster and the orange blocks were perhaps formed under thermodynamic conditions. Form 1I cocrystals could also be produced from the variety of common solvents. Cocrystallization of FS with 2,2'-bipyridine (2BPY) and 4-aminopyridine (4AP) gave colorless cocrystals 2 and 3, respectively, and did not exhibit polymorphism. The single-crystal X-ray structures, powder X-ray diffraction, photophysical characterization, differential scanning calorimetry, hot stage microscopy studies, and density functional theory (DFT) calculations provide insight into the structure property relationship. The common structural features observed in all of the structures is the formation of sandwich motifs comprising FS and pyridines through pi-stacking interactions. These motifs are linked differently through hydrogen bonding interactions in all three directions. The significant color difference between the two cocrystals dimorphs could be attributed to the different pi-stacking patterns and hydrogen bonding interactions between molecules of FS and 4BPY in their cocrystal structures. Investigation on the origin of the color difference using DFT calculations revealed the decrease in HOMO-LUMO gap for form 1II cocrystals (orange) compared to form 1I crystals (light yellow). The crystal-to-crystal thermal transformation of form 1I crystals to form 1II crystals of 1 suggests the role of pi-stacking assemblies in driving the self-assembly.</p>1 aSangtani, Ekta1 aSahu, Sanjay, Kumar1 aThorat, Shridhar, H.1 aGawade, Rupesh, L.1 aJha, Kunal, K.1 aMunshi, Parthapratim1 aGonnade, Rajesh, G.  uhttps://library.ncl.res.in/content/furosemide-cocrystals-pyridines-interesting-case-color-cocrystal-polymorphism-001514nas a2200277   4500008004100000022001400041245015400055210006900209260000800278300001400286490000600300520045800306653000600764653003100770653001400801653007000815653004300885653001900928100002700947700002400974700003200998700002501030700002401055700002601079856013101105       2017                        eng d  a2365-654900aFacile one-pot multi-component synthesis of spirooxindoles and 3, 3 `-disubstituted oxindoles via sp(3) C-H activation/functionalization of azaarenes0 aFacile onepot multicomponent synthesis of spirooxindoles and 3 3  cSEP  a9147-91520 v23 a<p>A novel one-pot multicomponent reaction (MCR) protocol has been demonstrated for the first time for sustainable and facile synthesis of spirooxindoles and 3, 3 `-disubstituted oxindoles in an excellent yield via sp(3) C-H activation/functionalization of 2-methyl azaarenes and (2-azaaryl)methanes with isatin, active methylene compounds using eco-friendly heterogeneous, reusable silica-supported dodecatungstophosphoric acid (DTP/SiO2) catalyst.</p>10a310a3'-disubstituted oxindoles10aazaarenes10asilica-supported dodecatungstophosphoric acid (DTP/SiO2) catalyst10asp(3) C-H activation/functionalization10aspirooxindoles1 aPathan, Mohsinkhan, Y.1 aChavan, Santosh, S.1 aShaikh, Taufeekaslam, M. Y.1 aThorat, Shridhar, H.1 aGonnade, Rajesh, G.1 aMulla, Shafeek, A. R.  uhttps://library.ncl.res.in/content/facile-one-pot-multi-component-synthesis-spirooxindoles-and-3-3-disubstituted-oxindoles-sp301409nas a2200229   4500008004100000022001400041245007000055210006900125260000800194300001400202520068900216653001300905653001600918653002100934653002600955653002100981653002001002100001901022700002401041700001901065856009501084       2018                        eng d  a1434-193X00aFirst total synthesis of the proposed structure of pandangolide 10 aFirst total synthesis of the proposed structure of pandangolide   cJUL  a3352-33643 a<p>The first total synthesis of the proposed structure of pandangolide 1 is reported. The synthesis was carried out using both an organocatalytic approach and a chiral-pool approach. The required stereochemistry at C-3 and C-5 was installed by using an organocatalytic aldol reaction and a stereoselective ketone reduction. The construction of the 12-membered core was achieved by 2-methyl-6-nitrobenzoic anhydride-mediated Shiina lactonization. The structure of target molecule was confirmed unambiguously by single-crystal X-ray analysis, but the optical rotation and NMR spectroscopic data of the synthetic pandangolide 1 were found to be inconsistent with the natural product.</p>10alactones10aMacrocycles10aNatural products10astructure elucidation10asynthesis design10aTotal synthesis1 aShow, Krishanu1 aGonnade, Rajesh, G.1 aKumar, Pradeep  uhttps://library.ncl.res.in/content/first-total-synthesis-proposed-structure-pandangolide-101359nas a2200181   4500008004100000022001400041245016700055210006900222260000900291300001400300490000700314520063400321100002600955700001900981700002401000700002201024856013101046       2019                        eng d  a1523-706000aFe(III)-Catalyzed diastereoselective friedel-crafts alkylation-hemiketalization-lactonization cascade for the synthesis of polycyclic bridged 2-chromanol lactones0 aFeIIICatalyzed diastereoselective friedelcrafts alkylationhemike  cAPR   a2629-26330 v213 a<p>An unprecedented Fe(III)-catalyzed Friedel-rafts alkylation-hemiketalization-lactonization cascade of electron-rich hydroxy arenes and distinctively functionalized unsaturated 4-keto esters is developed for the construction of polycyclic bridged 2-chromanol lactones. Following this simple and facile protocol, a broad range of products was prepared in good to excellent yields as a single diastereomer. An unusual conglomerate (enantiomerically pure polymorph) of 3ac is reported along with the absolute stereochemistry, and the remaining products were rigorously confirmed by single-crystal X-ray analysis and analogy.</p>
1 aBorade, Balasaheb, R.1 aNomula, Rajesh1 aGonnade, Rajesh, G.1 aKontham, Ravindar  uhttps://library.ncl.res.in/content/feiii-catalyzed-diastereoselective-friedel-crafts-alkylation-hemiketalization-lactonization02533nas a2200277   4500008004100000245016800041210006900209260000800278300001200286490000700298520154600305653003001851653001901881653002101900653002201921653001601943653001501959100002401974700002501998700002402023700002402047700001702071700002402088700002402112856011902136       2020                        eng d00aFive concomitant polymorphs of a green fluorescent protein chromophore (GFPc) analogue: understanding variations in photoluminescence with pi-stacking interactions0 aFive concomitant polymorphs of a green fluorescent protein chrom  cOCT  a850-8640 v763 a<p>The synthetically modified green fluorescent protein chromophore analogue 3,4,5-trimethoxybenzylidene imidazolinone (1) yielded five polymorphs (I, II, III, IV, V) concomitantly irrespective of the solvent used for crystallization. The pentamorphic modification of 1 is solely due to the interplay of iso-energetic weak intermolecular interactions in molecular associations as well as the conformational flexibility offered by a C-C single bond, which connects the electron-deficient moiety imidazolinone with the electron-rich trimethoxybenzylidene group. A common structural feature observed in all the polymorphs is the formation of a `zero-dimensional' centrosymmetric dimeric unit through a short and linear C-H center dot center dot center dot O hydrogen bond engaging phenyl C-H and imidazolinone carbonyl oxygen. However, the networking of these dimeric units showed a subtle difference in all the polymorphs. The 2D isostructurality was observed between polymorphs I, II and III, while the other two polymorphs IV and V revealed only `zero-dimensional' isostructurality. The different fluorescence emissions of Form I (blue) and Forms II to V (yellow) were attributed to the differences in pi-stacking interactions. It shows that one can modulate the photophysical properties of these smart materials by slightly altering their crystal structure. Such an approach will aid in developing new multi-colour organic fluorescent materials of varying crystal structures for live-cell imaging and fluorescent sensing applications.</p>
10agreen fluorescent protein10ahydrogen bonds10aisostructurality10aphotoluminescence10api-stacking10aPolymorphs1 aMali, Bhupendra, P.1 aDash, Soumya, Ranjan1 aNikam, Shrikant, B.1 aPuthuvakkal, Anisha1 aVanka, Kumar1 aManoj, Kochunnoonny1 aGonnade, Rajesh, G.  uhttps://library.ncl.res.in/content/five-concomitant-polymorphs-green-fluorescent-protein-chromophore-gfpc-analogue01380nas a2200241   4500008004100000022001400041245016500055210006900220260000900289300001200298490000700310520049500317653002200812653002100834653002500855653001900880653001200899100002400911700002500935700002800960700002400988856012601012       2020                        eng d  a1861-472800aFuran-derived chiral bicycloaziridino lactone synthon: collective syntheses of oseltamivir phosphate (Tamiflu), (S)-pipecolic acid and its 3-hydroxy derivatives0 aFuranderived chiral bicycloaziridino lactone synthon collective   cFEB   a415-4240 v153 a<p>A unified synthetic strategy for oseltamivir phosphate (tamiflu), (S)-pipecolic acid, and its 3-hydroxy derivatives from furan derived common chiral bicycloaziridino lactone synthon is described here. Key features are the short (4-steps), enantiopure, and decagram-scale synthesis of common chiral synthon from furan and its first-ever application in the total synthesis of biologically active compounds by taking the advantages of high functionalization ability of chiral synthon.</p>
10aAziridine synthon10aChiral auxiliary10acollective synthesis10aPipecolic acid10aTamiflu1 aChavan, Subhash, P.1 aKadam, Appasaheb, L.1 aShinde, Shrikrishna, S.1 aGonnade, Rajesh, G.  uhttps://library.ncl.res.in/content/furan-derived-chiral-bicycloaziridino-lactone-synthon-collective-syntheses-oseltamivir01312nas a2200193   4500008004100000022001400041245016900055210006900224260000900293300001400302490000700316520055000323100002400873700002300897700002200920700002500942700002400967856012700991       2021                        eng d  a0022-326300aFormal synthesis of (-)-quinagolide: diastereoselective ring expansion via a bicyclic aziridinium ion strategy to access the octahydrobenzo[g]quinoline architecture0 aFormal synthesis of quinagolide diastereoselective ring expansio  cJUL   a9344-93520 v863 aThe diastereoselective formal synthesis of (-)-quinagolide, a D-2 receptor agonist, has been achieved. The synthesis started from L-pyroglutamic acid and relied on utilization of (a) a stereospecific catalytic hydrogenation and diastereoselective Horner-Emmons-Michael cascade to obtain functionalized prolinate, (b) a Lewis acid mediated Pummerer cyclization to construct a tricyclic fused ring system, and (c) a diastereoselective ring expansion via a bicyclic aziridinium intermediate to access the required 3-substituted piperidine scaffold.1 aChavan, Subhash, P.1 aKawale, Sanket, A.1 aPisal, Mahesh, M.1 aKadam, Appasaheb, L.1 aGonnade, Rajesh, G.  uhttps://library.ncl.res.in/content/formal-synthesis-quinagolide-diastereoselective-ring-expansion-bicyclic-aziridinium-ion