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The development of new strategies for the synthesis of β-lactams and their derivatives remains at the forefront of organic synthesis. The copper(I)-catalyzed cycloaddition of a terminal alkyne and a nitrone, the Kinugasa reaction, leading to the formation of a β-lactam has recently drawn to the attention of organic chemists because of its wide scope as well as interesting mechanism. This report aims to give an account of developments in this area with particular emphasis on asymmetric examples. 1 Introduction 2 Synthesis of β-Lactams Using the Kinusaga Reaction 3 Asymmetric Kinugasa Reaction 4 Intramolecular Kinugasa Reaction 5 Kinugasa Reactions under Click Chemistry Conditions 6 Proline-Mediated Kinugasa Reaction 7 Kinugasa Reaction in the Synthesis of Peptidomimetics 8 Conclusion [ABSTRACT FROM AUTHOR]

Abstract: Cyclam-based enediynes 1–3 have been synthesized for the first time either by direct bis- or tetra-alkylation of the cyclam or via double alkylation of the 1,8-bis-sulfonyl derivative. The enediyne 1 readily forms a complex with Ni(II), which also lowered the onset temperature for Bergman cyclization of the parent enediyne by 60°C. In the presence of a co-oxidant, MMPP, the Ni-complex can cleave ds-DNA into the nicked relaxed form at micromolar concentrations. [Copyright &y& Elsevier]

Abstract: A novel pyridine diamine-based cyclic enediyne 1 was synthesized by bis-N-alkylation of 2,6-bis-sulfonamido pyridine 6 followed by deprotection with thiophenol. A variety of salts 1a–c of the parent amine 1 were prepared. Thermal reactivity studies indicated a dependence of the reactivity upon the extent of salt formation. This observation may be useful in pH-based design of enediynes. [Copyright &y& Elsevier]

The synthesis and chemical reactivity of pyridazinedione-based enediynes (1, 2) are described. Both of these enediynes, namely the dihydro compound 1 and its corresponding tetrahydro analogue 2, were prepared by double N,O-alkylation of the corresponding heterocyclic system with the acyclic enediynyl dibromide 8 in good yields. Their single-crystal X-ray structures revealed similar c, d distances (distance between the acetylenic carbons undergoing covalent connection in Bergman cyclization). Interestingly, these molecules undergo Bergman cyclization at different rates, and the reactivity is shown to be dependent upon the state of hybridization of C-4 and C-5 atoms of the parent heterocyclic ring. [ABSTRACT FROM AUTHOR]

An unexpected one-pot conversion of Tms-substituted 3-ethynyl-4-chromenones to ketals of type (III) is reported. [ABSTRACT FROM AUTHOR]

Abstract: A green protocol (compared to the existing methodology) for carrying out Garratt–Braverman cyclization has been developed. The method involves stirring a pre-absorbed bispropargyl sulfone/ether/sulfonamide over basic alumina. The reaction with sulfones was over within 10–15min at room temperature whereas for the ether/sulfonamide the reaction took 6–8h at 130°C. The products, aryl naphthalene derivatives, are obtained by simple filtration through Celite, in excellent yields. [Copyright &y& Elsevier]

Abstract: We report the synthesis of azobenzene template based sulfonamides 1 and 2 for capture of Human Carbonic Anhydrase II (HCAII). Out of these, 1 showed successful capturing of the protein, only when it is photo-isomerized to the Z form thus demonstrating the importance of spatial proximity of the reactive and selective functionalities. [Copyright &y& Elsevier]

Abstract: The asymmetric cyclopropanation of cinnamoyl amides derived from amino acids with CH2N2 in the presence of catalytic Pd(OAc)2 has been studied. The reaction proceeded with moderate to excellent diastereoselection. However, the selectivity depends upon the amino acid side chain as well as the electronic nature of the cinnamoyl moiety. [Copyright &y& Elsevier]

Sodium sulfide in methanol is successfully used for the silyl deprotection of substrates (I) and (III). [ABSTRACT FROM AUTHOR]

The four-component Ugi reaction is applied to synthesize biotin and rhodamine tagged compounds (V) of which a series of photoaffinity probes (VIII) for 2-OG oxygenase is derived. [ABSTRACT FROM AUTHOR]