Ponnusamy Shanmugam

  • Citations Per Year
Learn More
A novel regioselective synthesis of a number of functionalized 3-spiropyrrolizidine and 3-spiropyrrolidine oxindoles from Baylis-Hillman adducts of isatin and heteroaldehydes via [3+2] cycloaddition of azomethine ylides in excellent yields has been reported.
An activation of the pyridine nucleus has been achieved via 1,5-electrocyclization of vinyl pyridinium ylides generated from bromo isomerized Morita-Baylis-Hillman adducts of isatin and pyridine under basic conditions. The method has been successfully applied for an efficient synthesis of a number of 3-spirodihydroindolizine-2-oxindoles, which have been(More)
[reaction: see text] A novel and powerful reagent system R(3)Al-R'(3)SiOTf for the one-pot alkylation-silylation reaction of epoxides was discovered, and the reactions of various epoxides with the new reagent system have been demonstrated to occur stereospecifically giving rise to the corresponding alkylation-silylation products in excellent yields.
The chemistry phosphorus and sulfur ylides have been exploited for a facile, short and efficient synthesis of 3-spirocyclopentene- and 3-spiropyrazole-2-oxindoles from E- and Z-isomers of bromo derivatives of Morita-Baylis-Hillman adducts of isatin with Ph(3)P/activated alkene/K(2)CO(3) and Me(2)S/DEAD/K(2)CO(3), respectively, via [3 + 2]-annulation(More)
NaN3-ROH/ArOH has been found to be an efficient reagent for 1,3-amino alkoxylation and 1,3-amino phenolation of a maleimide-derived MBH adduct of isatin via domino azidation-Michael addition. Following this protocol, with NaN3-formalin, a one-pot synthesis of 3-spiro-1,2-dihydropyrrolooxazine-5,7-dione-oxindole has been achieved. In an aprotic medium, the(More)
A facile and efficient binary Cu(I)/Cu(II) catalyzed one-pot, three-component synthesis of 2-amino-3-iminoethenylidene-2-indolones in excellent yield has been achieved. Remarkably, these newly synthesized, stable merocyanine dye analogues showed strong luminescence in the blue region with large Stokes shifts.
Pyranoquinoline alkaloids, which possess inter­ esting pharmacological properties are known [1, 2] to occur in the plant family Rutaceae. The alka­ loids, khaplofoline (1) and ribalinine (2), isolated respectively from Haplophyllum foliosum (Vved) [3] and Balfourodendron riedelianum [4], members of the rutaceae, are structurally proven to be of pyrano(More)
Activated alkene dependent one-pot, three-component aza-Morita-Baylis-Hillman (aza-MBH) reaction of ferrocenealdehyde afforded simple aza-MBH adduct of ferrocenealdehyde, unusual piperidine, β-amino acid residue, and γ-ketoester derivatives of ferrocene in good yield. The synthetic protocol with MVK has led to an unexpected ferrocenyl piperidine derivative(More)
The plant family Rutaceae is known [1, 2] to be a prolific source of furoquinoline and pyranoquinoline alkaloids. Along with them acridine alka­ loids [3, 4] have also been isolated from several members of the same plant family. Recently furanfused acridine systems such as 1 l-methylfuro(2,3-c)acridan-6(l lH)one (1) have also been reported [5-7] to occur in(More)
A facile method utilizing RCOX/K2CO3 as a novel reagent for conjugate addition of hydrogen halide, in addition to tertiary (3°)-hydroxyl protection that leads to the synthesis of functionalized β-halo Morita-Baylis-Hillman ester appended oxindoles, has been developed. The diastereoselective one-pot O-acylation-hydrohalogenation observed cannot otherwise be(More)
  • 1