Synthesis of natural products and Bio active molecules
13
Scopus Publications
Scopus Publications
Synthesis of functionalized cyclohexenols via a domino Michael addition-Dieckmann cyclization-isomerization reaction sequence Manickam Bakthadoss, Gandhi Murugan, Jayakumar Srinivasan Tetrahedron Letters, 2015 A simple and new protocol for the synthesis of functionalized cyclohexenols via a domino Michael addition followed by Dieckmann cyclization and enolization reaction sequence has been described. A wide variety of activated olefins were utilized in the domino cyclization along with Baylis–Hillman derivatives to afford libraries of functionalized cyclohexenols in good yields.
Methyl 4'-(4-fluorophenyl)-1'-methyl-3'-nitromethyl-2-oxospiro[indoline-3, 2'-pyrrolidine]-3'-carboxylate B. K. Revathi, S. Sathya, G. Usha, G. Murugan, M. Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2013 In the title compound, C21H20FN3O5, the the pyrrolidine ring makes dihedral angles of 84.91 (6) and 62.38 (7)° with the oxindole unit and the fluorophenyl ring, respectively. The pyrrolidine ring assumes an envelope conformation with the spiro C atom as the flap. The crystal packing features weak N—H...N and C—H...O hydrogen bonds.
(E)-2-(2-Formylphenoxymethyl)-3-phenylprop-2-enenitrile K. Swaminathan, K. Sethusankar, G. Murugan, M. Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2011 In the title compound, C17H13NO2, the dihedral angle between the benzene and the phenyl ring is 65.92 (7)°. The carbonitrile side chain is almost linear, the C—C—N angle being 175.55 (14)°. The crystal structure is stabilized by intermolecular C—H⋯O interactions.
1-Methyl-3-p-tolyl-3,3a,4,9b-tetra-hydro-1H-chromeno[4,3-c] isoxazole-3a-carbonitrile Rajeswari Gangadharan, K. Sethusankar, Gandhi Murugan, Manickam Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2011 In the title compound, C19H18N2O2, the dihedral angle between the mean planes of the fused chromeno and isoxazole units is 43.71 (7)°. The isoxazole and pyran rings exhibit envelope and half chair conformations, respectively. The crystal packing is stabilized by intermolecular C—H⋯π interactions.
3-(3-Chloro-phen-yl)-1-methyl-3,3a,4,9b-tetra-hydro-1H-chromeno[4,3-c] isoxazole-3a-carbonitrile K. Swaminathan, K. Sethusankar, G. Murugan, M. Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2011 In the title compound, C18H15ClN2O2, the five-membered isoxazole ring adopts an envelope conformation [the deviation of the N atom is 0.3154 (15) Å] and the six-membered pyran ring adopts a half-chair conformation. The mean plane through all atoms of the isoxazole ring forms dihedral angles of 47.98 (8)° with the mean plane of the chromene ring system and 75.10 (9)° with the chlorobenzene ring.
1-Methyl-3-(2-methylphenyl)-3,3a,4,9b-tetra-hydro-1H-chromeno[4,3-c][1,2] oxazole-3a-carbonitrile K. Swaminathan, K. Sethusankar, G. Murugan, M. Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2011 In the title compound, C19H18N2O2, the five-membered isoxazole ring adopts an envelope conformation and the deviation of the N atom from the mean plane of the isoxazole ring is −0.3256 (11) Å. The pyran ring adopts a half-chair conformation. The isoxazole ring forms dihedral angles of 44.07 (7) and 84.23 (7)° with the pyran and methylbenzene rings, respectively. The molecular structure is stabilized by weak C—H⋯π interactions.
1-Methyl-3-(naphthalen-1-yl)-3,3a,4,9b-tetra-hydro-1H-chromeno[4,3-c] isoxazole-3a-carbonitrile Rajeswari Gangadharan, K. SethuSankar, Gandhi Murugan, Manickam Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2011 In the title compound, C22H18N2O2, the pyran ring of the chromene unit is fused with an isoxazole ring, which adopts an N-envelope conformation with the N atom lying 1.3291 (14) Å from the mean plane of the remaining ring atoms [maximum deviation = 0.341 (2) Å]. The dihedral angle between the isoxazole and chromene units is 43.74 (8)° and that between the iosxazole ring and the naphthalene ring system is 58.82 (8)°. In the crystal, the molecules are linked by weak C—H⋯π interactions.
3-(2-Methylbenzylidene)-2,3-dihydro-1,5-benzothiazepin-4(5H)-one D. Sridevi, Sundari Bhaskaran, G. Usha, G. Murugan, M. Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2011 In the crystal structure of the title compound, C17H15NOS, the molecules form centrosymmetric dimers through pairs of N—H⋯O hydrogen bonds. The seven-membered ring adopts a distorted half-chair conformation.
Methyl 3-(4-fluorophenyl)-1-methyl-1,2,3,3a,4,9bhexahydrochromeno[4,3-b] pyrrole-3acarboxylate G. Chitra Devi, Sundari Bhaskaran, G. Usha, G. Murugan, M. Bakthadoss Acta Crystallographica Section E Structure Reports Online, 2011 In the title compound, C20H20FNO3, the pyrrolidine and benzopyran rings adopt half chair and twisted half chair conformations, respectively. The carboxylate group is almost perpendicular to the pyran ring [89.4 (1)°].
Highly stereoselective synthesis of tricyclic chromenoisoxazolidines by intramolecular 1,3-dipolar cycloadditions Manickam Bakthadoss, Gandhi Murugan European Journal of Organic Chemistry, 2010 The novel and simple synthesis of tricyclic chromenoisoxazolidine frameworks by using Baylis-Hillman derivatives through in situ formation of nitrones followed by an intramolecular [3+2] dipolar cycloaddition reaction sequence is described. The new [3+2] cycloaddition reaction leads to a novel class of angularly substituted fused tricyclic chromenoisoxazolidines, creating two rings and three contiguous stereocenters, one of them being a tetrasubstituted carbon center. Fused tricyclic compounds were obtained in a highly stereoselective fashion with high yields.
