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A novel methodology for the construction of various secondary (4 examples), tertiary amides (31 examples), and imides (16 examples) by a Cobalt(II) catalyzed oxidative amide coupling in aqueous media. The Co(III)‐TMC was reacted with N‐Heteroatom Carbene to form active catalyst Co(II)NHC‐TMC in situ which involves in the coordination with Breslow's intermediate and SET for the activation of aldehyde and amides. The mechanism for activation of amide and amine differs on the basis of SET based nucleophilic addition and ligand exchange respectively. The regeneration of the catalyst was achieved using Fe(III)(EDTA)‐H2O2 as oxidant. The use of Co(II)TMC‐O2 was also found equally efficient in the process. The method is found regioselective for N−H activation in the presence of equally susceptible ortho‐C−H bond activation. And amines were found more susceptible then the corresponding amide for the reaction.

In search of non-platinum based anticancer drugs, we have synthesized and characterized a new class of three gadoliniumand a carbon nanotube composite, 1@CNT 4. The three oligopeptides, L 1 -L 3 were prepared in a novel synthetic route using tetramethyl benzotriazolyl uronium hexaflurophosphate (HBTU) as a peptide coupling reagent. Confocal microscopic analysis of the gadolinium(III)-oligopeptides, 1, 2 and CNT composite, 1@CNT 4 indicate that they display white and green light emissions upon excitations at λ, 405 and 488 nm with characteristic patterns. The oligopeptides, L 1 & L 3 display in vitro anticancer activity on HeLa cells with IC 50 values in one mM concentration whereas the IC 50 of RGD-based oligopeptide was found to be 1 μM. The IC 50 of gadolinium(III)-oligopeptide, 1 and the CNT composite, 4 were found to be 1 μM and 10 nM. The transmission electron microscopic investigation of the HeLa cells treated with the composite 4 confirm the cellular uptake and indicate the presence of CNTs in the cytoplasm and that CNTs appear like bullets carrying the gadolinium(III)-triaspartate, 1.