Molecular iodine-promoted efficient construction of isatins from 2′-aminophenylacetylenes, 2′-aminostyrenes, and 2′-amino-β-ketoesters is developed via oxidative amidation of sp, sp2, and sp3 C–H bonds. The reaction involves consecutive iodination, Kornblum oxidation, and intramolecular amidation in a single reactor. The present method meets all of the atom and redox economy principles.

Iodine-Mediated C–H Functionalization of sp, sp2, and sp3 Carbon: A Unified Multisubstrate Domino Approach for Isatin Synthesis

A new era in the organic synthetic world is demanding greener protocols for the execution of reactions. As the world is progressing towards fewer natural resources and high energy input, organic chemists are keeping a strict eye on seeking alternative methods to rise above these difficult situations. Amongst all reactions, oxidative reactions are the ones which require the major use of expensive metals, and harsh and toxic reagents owing to which the need of the green hour indispensably calls for a contemporary solution to existing conventional methodologies. Hereby, this review talks about the combined role of molecular iodine and DMSO in revolutionizing synthetic methodologies, especially reactions related to the oxidation process. In particular, this review highlights the construction of the C–N bond in forging biologically potent molecules through this indispensable tool.

Iodine/DMSO oxidations: a contemporary paradigm in C–N bond chemistry

Novel molecular iodine catalyzed cyclization reactions of 2-amino anilines with aryl alkyl ketones under oxidant and metal-free conditions are described. The reaction likely involves sequential C–N bond formation followed by C(CO)–C(alkyl) bond cleavage. Various 2-substituted benzimidazoles are obtained in moderate to good yields in a single step from readily available acetophenones, propiophenones, and phenylacetophenones.

Benzimidazoles from Aryl Alkyl Ketones and 2-Amino Anilines by an Iodine Catalyzed Oxidative C(CO)–C(alkyl) Bond Cleavage

Multicomponent and One-pot Syntheses of Quinoxalines

An I2-promoted, metal-free domino protocol for one-pot synthesis of 1,3,4-oxadiazoles has been developed via oxidative cleavage of C(sp2)–H or C(sp)–H bonds, followed by cyclization and deacylation. In this reaction, the use of K2CO3 as a base is found to be an essential factor in the cyclization and the C–C bond cleavage. This procedure proceeded smoothly in moderate to high yields with good functional group compatibility.

Iodine-Mediated Domino Oxidative Cyclization: One-Pot Synthesis of 1,3,4-Oxadiazoles via Oxidative Cleavage of C(sp(2))-H or C(sp)-H Bond.

Iodine-mediated oxidative annulation for one-pot synthesis of pyrazines and quinoxalines using a multipathway coupled domino strategy.

The present article illustrates the serendipitous discovery of a cationic-lipid-based human DNA ligase (hLig) I inhibitor and the development of siRNA delivering, a hLigI-targeted cationic-lipid-based nonviral vector. We have tested a small in-house library of structurally similar cationic lipo-anisamides for antiligase activity, and amongst tested, N-dodecyl-N-(2-(4-methoxybenzamido)ethyl)-N-methyldodecan-1-ammonium iodide (C12M) selectively and efficiently inhibited the enzyme activity of hLigI, compared to other human ligases (hLigIIIβ and hLigIV/XRCC4) and bacterial T4 DNA ligase. Furthermore, upon hydration with equimolar cholesterol, C12M produced antiligase cationic liposomes, which transfected survivin siRNA and showed significant inhibition of tumor growth.

siRNA Delivery Using a Cationic-Lipid-Based Highly Selective Human DNA Ligase I Inhibitor.

An efficient iodine-mediated oxidative annulation of aryl acetylenes–arylethenes–aromatic ketones with 1,2-diamines for the synthesis of pyrazines and regioselective synthesis of quinoxalines is presented. A multipathway coupled domino approach has been developed for the one-pot synthesis of 1,4-diazines with high functional group compatibility.

Muktapuram Prathap Reddy

Papers

Iodine-mediated oxidative annulation for one-pot synthesis of pyrazines and quinoxalines using a multipathway coupled domino strategy.

siRNA Delivery Using a Cationic-Lipid-Based Highly Selective Human DNA Ligase I Inhibitor.

Iodine-Mediated Oxidative Annulation for One-Pot Synthesis of Pyrazines and Quinoxalines Using a Multipathway Coupled Domino Strategy.

Access to Di‐ and Trisubstituted Oxazoles by NBS‐Mediated Oxidative Cyclization of N‐Acyl Amino Acid Derivatives.