Anwar Shamim

Functionalization of protected tyrosine via Sonogashira reaction: synthesis of 3-(1,2,3-triazolyl)-tyrosine

Abstract1,2,3-Triazol tyrosines were synthesized from tyrosine alkynes that were in turn prepared via Sonogashira cross-coupling reaction. The tyrosine alkynes were subjected to click-chemistry reaction conditions leading to the corresponding 3-(1,2,3-triazolyl)-tyrosines in yields ranging from moderate to good.

Ytterbium(III)-catalyzed three-component reactions: synthesis of 4-organoselenium-quinolines

4-Organoselenium-quinolines were synthesized via model multi-component Povarov (MCR) reactions between p-anisidine, ethyl glyoxylate and ethynyl(phenyl)selane, catalyzed by the Lewis acid Yb(OTf)3, with yields ranging from moderate to good. This method is advantageous in that there is no requirement for an oxidant and that the reaction has a wide scope. These 4-organoselenium-quinolines allowed access to 4-alkynyl-quinolines, which were synthesized via copper free Sonogashira cross-coupling reactions catalyzed by a new palladium catalyst that employs an oxazoline derivative as a ligand. A plausible mechanism was proposed based on HRMS studies.

Synthesis of enyne and aryl vinyl sulfoxides: functionalization via Pummerer rearrangement.

An efficient methodology for the synthesis of aryl-substituted vinyl sulfoxides through direct substitution of aryl-substituted alkynyl grignard reagents on menthyl-p-toluenesulfinate followed by Suzuki–Miyaura cross-coupling reaction has been developed. It has also been described that the reaction of alkyl-substituted and cycloalkyl-substituted alkynyl grignard reagents with menthyl-p-toluenesulfinate led to two products, i.e., alkynyl sulfoxide derivatives, as a result of substitution, and enyne sulfoxide derivatives, which resulted from substitution followed by Michael type addition. It was possible to selectively synthesize the enyne sulfoxide derivatives by changing the concentration of the grignard reagent. These alkenyl sulfoxides were transformed into the corresponding

Crystal structure of [(2R,3R,4S)-3,4-bis(acet­yloxy)-5-iodo-3,4-di­hydro-2H-pyran-2-yl]methyl acetate

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Lewis-acid catalyzed N-acyliminium ion cyclodimerization: synthesis of symmetrical 1,4-dioxanes

α-thio aldehydes in high yields via additive Pummerer rearrangement.

Synthesis and applications of 4-substituted 1-(4-iodophenyl)pyrrolidine-2,5-diones

We have developed an efficient, CuI-catalyzed, microwave-assisted method for the synthesis of bis-1,2,3-triazole derivatives starting from a 3,4,6-tri-

Synthesis of Glycosyl Azides and Their Applications Using CuAAC Click Chemistry to Generate Bis- and Tris(triazolyl)glycosyl Derivatives

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