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A practical method for the selective and controlled oxidation of thioglycosides to corresponding glycosyl sulfoxides and sulfones is reported using urea–hydrogen peroxide (UHP). A wide range of glycosyl sulfoxides are selectively achieved using 1.5 equiv of UHP at 60 °C while corresponding sulfones are achieved using 2.5 equiv of UHP at 80 °C in acetic acid. Remarkably, oxidation susceptible olefin functional groups were found to be stable during the oxidation of sulfide.

A number of novel 7-O-noscapine glycoconjugates have been synthesized starting from noscapine, an alkaloid found in the opium plant, via two successive steps. The first step is a selective 7-O-demethylation of noscapine and the next is a subsequent propargylation which affords 7-O-propargyl noscapine (3) in good yield. The structure was confirmed by extensive spectroscopic data including single crystal X-ray data. The 1,3-dipolar cycloaddition of the developed noscapine derivative 3 with glycosyl azides 6a–m was investigated to give the triazole-linked second-generation noscapine analogs in their glycoconjugate forms (8a–m) to augment the therapeutic efficacy of noscapine.

A series of diverse glycosyl 1,2-azido alcohols, obtained from readily available carbohydrates, were converted to structurally varied rare and novel sugar derived morpholine fused [5,1-c]-triazoles via a one-pot strategy. After incorporating a propargyl functionality at the hydroxyl group of the sugar derived 1,2-azido alcohols, the resulting in situ generated azido–alkyne affords numerous C- and O-glycosyl bicyclic ring systems with medicinal value via a metal free cycloaddition reaction. The structures of all the developed molecules have been elucidated using 1H NMR, 13C NMR, IR and MS spectroscopy.

Thiobenzoate complexes of Cu(I), [Cu(SCOPh)]n(1), [Cu(bpy)(µ-SCOPh)]2 (2), [Cu(dppf)(SCOPh)] (3), [where bpy = 2,2′-bipyridyl; dppf = [1,1′-bis(diphenylphosphino)ferrocene] were synthesized and structurally characterized by X-ray crystallography. NBO calculations were performed to understand the nature of the Cu–Cu (2.706 A) interaction in 2. All of the complexes were found to catalyze azide–alkyne cycloaddition for the regioselective synthesis of glycoconjugate triazoles under click reaction.

Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi-221 005, Uttar Pradesh, India E-mail : Tiwari_chem@yahoo.co.in Central Institute for Research on Cotton Technology, Matunga, Mumbai-400 019, India Manuscript received online 12 February 2015, accepted 04 March 2015 In addition to the wide range of pharmacological activities associated with β-lactams, their importance as synthetic intermediates in organic synthesis has been widely recognized. A series of glycosyl β-lactam of promising chemotherapeutic values has been developed from corresponding β-amino esters in good yield under mild reaction condition.

The synthesis of triazolyl azido alcohols from terminal alkyne via oxirane ring-opening of epichlorohydrin, followed by click reaction with alkynes, and subsequent azidation of chlorohydroxy triazoles was achieved under a one-pot methodology. The developed triazolyl azido alcohols were further utilized for the synthesis of a diverse range of morpholine-fused triazoles of chemotherapeutic value. The structure of all developed compounds has been elucidated using IR, NMR, MS, and elemental analysis, where four of them have been characterized by single-crystal X-ray analysis.