01957nas a2200253 4500008004100000022001400041245007900055210006900134260007400203300001200277490000700289520102700296653001801323653003701341653002301378653004501401100002401446700002501470700002801495700002501523700002201548700002201570856011101592 2016 eng d a0928-070700aSynthesis and characterization of superhydrophobic-superoleophilic surface0 aSynthesis and characterization of superhydrophobicsuperoleophili aVAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDSbSPRINGERcJUN a475-4810 v783 a

The binary superhydrophobic-superhydrophilic surface has been successfully achieved by a combination of nanoscale texture roughness on micro-textured cotton thread network by layer-by-layer deposition method through the single-step sol-gel route. Furthermore, microstructures with improved wettability were produced, in which silica nanotextures were grown without modifying the chemical method to form superoleophilic and superhydrophobic networks. A superoleophilic surface (oil contact angle 0A degrees) and a superhydrophobic coated cotton fabric with surface free energy of gamma (total) = 13. 23 +/- A 0.37 mJ m(-2) (water contact angle of 167 +/- A 1A degrees and a small sliding angle of 4 +/- A 1A degrees) were successfully obtained. The results were exemplified here by the creation of immiscible oils separation membranes, and the innumerable applications of this technology also include self-cleaning fabrics, antistaining fabrics, water purification, and antiwetting fabrics for military applications.

10acontact angle10aLayer-by-layer deposition method10asol-gel processing10aSuperhydrophobic-superoleophilic surface1 aMahadik, Satish, A.1 aPedraza, Fernado, D.1 aRelekar, Brahmanand, P.1 aParale, Vinayak., G.1 aLohar, Gaurav, M.1 aThorat, Sagar, S. uhttps://library.ncl.res.in/content/synthesis-and-characterization-superhydrophobic-superoleophilic-surface01154nas a2200169 4500008004100000022001400041245013300055210006900188260000900257300001200266490000700278520050200285100002200787700002200809700002200831856013100853 2018 eng d a1523-706000aSynthesis of furo[2,3-b]pyran-2-ones through Ag(I)- or Ag(I)-Au(I)-catalyzed cascade annulation of alkynols and alpha-ketoesters0 aSynthesis of furo23bpyran2ones through AgI or AgIAuIcatalyzed ca cFEB  a872-8750 v203 a

Ag(I)- or Ag(I)-Au(I)-catalyzed cascade annulation of alkynols (5-hexyn-1-ol systems) with a-ketoesters involving a dual activation process (pi and sigma) has been developed for the first time. This reaction proceeds through cycloisomerization of alkynol to give the 6-endo-enol ether followed by annulation with an alpha-ketoester to furnish furo[2,3-b]pyran-2-ones in good yields. Chemical structures of all products were rigorously confirmed by single crystal X-ray analysis and analogy.

1 aThorat, Sagar, S.1 aKataria, Priyanka1 aKontham, Ravindar uhttps://library.ncl.res.in/content/synthesis-furo23-bpyran-2-ones-through-agi-or-agi-aui-catalyzed-cascade-annulation-alkynols01327nas a2200169 4500008004100000022001400041245007100055210006500126260000900191300001600200490000700216520076900223100002200992700002601014700002201040856009501062 2021 eng d a0022-326300aStereoselective total synthesis of (+/-)-pleurospiroketals A and B0 aStereoselective total synthesis of pleurospiroketals A and B cOCT  a13572-135820 v863 aA full account of our efforts toward the stereoselective total synthesis of sesquiterpenoid-derived natural products (+/-)-pleurospiroketals A and B is described. Commercially available 3-methyl-2-cyclohexenone and 2,2-dimethyloxirane were used as key building blocks, and the substrate-controlled stereoselection was exploited to access the entire stereochemistry of these natural products. Initially, a planned synthetic route involving a [6,5]-bicyclic lactone intermediate was found to be insurmountable, and the later strategy comprising OsO4-NMO-mediated dihydroxylation of 3-methyl-2-cyclohexenone, followed by Luche reduction, Eschenmoser methylenation, and Bronsted acid-induced spiroketalization steps, was ultimately identified as the reliable strategy.1 aThorat, Sagar, S.1 aKrishna, Gamidi, Rama1 aKontham, Ravindar uhttps://library.ncl.res.in/content/stereoselective-total-synthesis-pleurospiroketals-and-b01576nas a2200157 4500008004100000022001400041245012400055210006900179260000800248300001400256490000600270520096900276100002201245700002201267856012901289 2021 eng d a2052-412900aStrategies for the synthesis of furo-pyranones and their application in the total synthesis of related natural products0 aStrategies for the synthesis of furopyranones and their applicat cMAY a2110-21620 v83 a

The furo-pyranone framework is widely present in the molecular structure of various biologically potent natural products and un-natural small molecules, and it represents a valuable target in synthetic organic chemistry and medicinal chemistry. In the last five decades, numerous innovative synthetic methodologies have been disclosed for these bis-oxacyclic fused heterocycles, expanding the scope of accessible building blocks, efficient and affordable catalysis, facile reaction conditions, and overall practicality of the process. In this comprehensive review article, we focus on showcasing the complete spectrum (from the first report in the 1970s to the latest disclosure in 2020) of efforts devoted towards the synthesis of diverse classes of furo-pyranones through systematization and critical analysis of the accumulated experimental knowledge and their elegant applications in total syntheses of biologically interesting related natural products.

1 aThorat, Sagar, S.1 aKontham, Ravindar uhttps://library.ncl.res.in/content/strategies-synthesis-furo-pyranones-and-their-application-total-synthesis-related-natural01579nas a2200205 4500008004100000022001400041245014300055210007100198260000800269300001200277490000600289520081600295100002401111700002201135700001801157700002601175700001701201700002201218856013301240 2022 eng d a2052-412900aSilver-catalyzed [3 + 3]-annulation cascade of alkynyl alcohols and α,β-unsaturated ketones for the regioselective assembly of chromanes0 aSilvercatalyzed 3 3annulation cascade of alkynyl alcohols and αβ cJAN a802-8090 v93 aAn unprecedented Ag(i)-catalyzed [3 + 3]-annulation of alkynyl alcohols (5-hexyn-1-ols) and α,β-unsaturated ketones is reported to construct simple to complex chromanes. This transformation begins with hydroalkoxylation of alkynol through C–C triple bond activation to give cyclic-enol ether, followed by intermolecular 1,4-addition and intramolecular 1,2-addition of enol ethers onto the enone and oxidative aromatization or Grob-type elimination steps. Facile reaction conditions, broad substrate scope, good to excellent yields, and atom economy are the salient features of this protocol. Isolation of the active pyran-tethered cyclohexadiene reaction intermediate, additional supporting experiments, and DFT calculations strongly support the experimental findings and corroborate our proposed mechanism.1 aNakate, Ashwini, K.1 aThorat, Sagar, S.1 aJain, Shailja1 aKrishna, Gamidi, Rama1 aVanka, Kumar1 aKontham, Ravindar uhttps://library.ncl.res.in/content/silver-catalyzed-3-3-annulation-cascade-alkynyl-alcohols-and-%CE%B1%CE%B2-unsaturated-ketones01950nas a2200253 4500008004100000022001400041245009600055210006900151260000900220490000700229520108400236653004101320653002501361653001501386653003001401100002501431700002201456700002101478700001901499700001701518700002401535700002201559856011501581 2025 eng d a1861-472800aStudies on the stereoselective synthesis of sacubitril via a chiral amine transfer approach0 aStudies on the stereoselective synthesis of sacubitril via a chi cMAR 0 v203 a

We present a comprehensive account of our efforts directed towards the synthesis of sacubitril, a neprilysin inhibitor used in combination with valsartan and marketed as Entresto (TM). Our initial approach to the formal synthesis of sacubitril employed a chiral pool strategy, utilizing (S)-pyroglutamic acid as a key building block and Cu(I)-mediated Csp2-Csp3 cross-coupling as a key transformation. Further investigations led to the development of chiral amine transfer (CAT) reagents-based stereoselective synthesis. This involved the E-selective construction of gamma-ylidene-butenolide from readily available biphenyl bromide and 4-pentynoic acid, the conversion of this butenolide to its ene-lactam using chiral amine, and substrate-controlled diastereoselective reduction of ene-lactam using Et3SiH or Pd/C, H2 (overall chiral amine transfer) as key transformations. Antipodal lactam intermediates were synthesized using corresponding chiral amines, and the stereochemical outcomes during the ene-lactam reduction with Et3SiH were rationalized by DFT studies.

10aChiral Amine Transfer (CAT) approach10aChiral pool approach10aSacubitril10astereoselective synthesis1 aSadanande, Megha, V.1 aThorat, Sagar, S.1 aSharma, Himanshu1 aSingh, Geetika1 aVanka, Kumar1 aGonnade, Rajesh, G.1 aKontham, Ravindar uhttps://library.ncl.res.in/content/studies-stereoselective-synthesis-sacubitril-chiral-amine-transfer-approach