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The switchable synthesis of 3-aminoindolines and 2′-aminoaryl acetic acids from the same substrates, 3-azido-2-hydroxyindolines, was developed through denitrogenative electrophilic amination of Grignard reagents. The key to success is the serendipitous discovery that the reaction conditions, including solvents and reaction temperature, can affect the chemoselectivity. It is noteworthy that isotope-labeling experiments revealed the occurrence of the aziridine intermediate in the production of 2′-aminoaryl acetic acids. [ABSTRACT FROM AUTHOR]

Use of 3-azidoindoles in organic synthesis remains a difficult task owing to their instabilities. Herein, we report a general and concise approach for tackling this problem by using 3-azidoindole surrogates. The surrogates are bench-stable, presumably due to the observed intramolecular O–Nβ bonding. The resultant fleeting intermediates undergo capturing in situ to afford 3-substitued indoles through formal ipso-substitution of the azide group by nucleophiles. In these investigations, we found that the fleeting 3-azidoindoles show a C3-electrophilic character for the first time. [ABSTRACT FROM AUTHOR]

Commodity polymer materials are now required to be environmentally friendly due to problems associated with resource depletion and low recycling rates, which has promoted the development of circular material systems. Herein, a novel concept is introduced, where a polymer is used as a source of a fertilizer. To demonstrate the viability of this concept, the chemical recycling of poly(isosorbide carbonate) (PIC) is presented as a model for the next generation of plastic-recycling systems. PIC, a bio-based polymer known for its excellent physical properties, undergoes a degradation reaction with aqueous ammonia. Monitoring the degradation behavior by 1H NMR and FT-IR spectroscopy as well as gel-permeation chromatography revealed that PIC completely decomposes within 6 h at 90 °C to afford isosorbide and urea. The utility of isosorbide and urea obtained from the degradation of PIC as fertilizers was demonstrated via plant-growth experiments. The generation of fertilizers via polymer degradation in the present study is expected to lead not only to innovative chemical recycling systems to address the environmental problems associated with polymer materials, but also to provide solutions to the food-production problems associated with the growth of the global population. [ABSTRACT FROM AUTHOR]

We introduce readily available ammonium hemiaminals as O-transfer reagents and commercially available acetonitriles as a primary amide enolate precursor. The combination serves as an amide enolate equivalent, thereby providing one-pot access to α-substituted indolylacetamides. A broad substrate scope and good functional group tolerance as well as gram-scale synthesis make this protocol highly attractive. Mechanistic experiments suggest that the cyano group is trapped by a hydroxy group of hemiaminals en route to the desired primary amides under metal-free conditions. [ABSTRACT FROM AUTHOR]

Enamines undergo α-indolization with ammonium salts in the presence of Et3N to form α-indolylketones. This is the first example of transition metal-, oxidant-, and fluorous solvent-free α-indolization of ketones. Key to the success of this convenient protocol was the use of in situ generated electrophilic indole species, as well as the use of enamines as a ketone enolate equivalent. [ABSTRACT FROM AUTHOR]

2,3-Dimethoxyindolines (DiMeOINs) have emerged as a latent electrophile in indium-catalyzed SNAr reactions. They are easily obtained from commercially available indoles and allowed access to 3-substituted indoles. The reaction proceeds via SNAr reactions of in situ generated 3-methoxyindoles. Formation of C2-substituted indoles was also possible utilizing the C2-nucleophilicity of DIMeOIN. Our protocol is user friendly as DiMeOIN is a bench-stable easy-to-handle crystalline reagent. [ABSTRACT FROM AUTHOR]

We have developed a copper-catalyzed Ritter-type reaction/cyclization cascade of anthranilic acids and nitriles, affording the quinazolin-4(3H)-ones. The cascade proceeds through a Ritter-type reaction capturing the iminoketene intermediates by nitriles. Furthermore, we found a novel Ritter-type reaction/condensation/intramolecular anti-Markovnikov hydroamination cascade, providing access to functionalized diazocines in one-pot. [ABSTRACT FROM AUTHOR]

Covering: 2012 to 2013. Previous review: Nat. Prod. Rep., 2013, 30, 694–752 This review covers the literature on simple indole alkaloids and those with a nonrearranged monoterpenoid unit from the beginning of 2012 up to the end of 2013, which includes newly isolated alkaloids, structure determinations, total syntheses and biological activities. [ABSTRACT FROM AUTHOR]

2,3-Dimethoxyindolines (DiMeOINs) have emerged as a latent electrophile in indium-catalyzed S N Ar reactions. They are easily obtained from commercially available indoles and allowed access to 3-substituted indoles. The reaction proceeds via S N Ar reactions of in situ generated 3-methoxyindoles. Formation of C2-substituted indoles was also possible utilizing the C2-nucleophilicity of DIMeOIN. Our protocol is user friendly as DiMeOIN is a bench-stable easy-to-handle crystalline reagent.

The regioselective synthesis of pyrano[3,2- e ]indole alkaloid fontanesine B by two different cyclizations is described. The complete regioselectivity is controlled by the C4 Pictet-Spengler cyclization, in which an iminium ion acts as a transient directing (TDG) group. Furthermore, carbolines were constructed by a new Bischler-Napieralski-type cyclization, in which an unprecedented trichloromethyl carbamate serves as a reactive group., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Obesity and other lipid metabolism-related diseases have become more prevalent in recent years due to drastic lifestyle changes and dietary patterns. Unsaturated vitamin E, tocotrienol (T3), represents one of the most fascinating naturally occurring compounds that has the potential to influence a broad range of mechanisms underlying abnormal lipid metabolism processes. However, its efficacy and mechanism have been uncertain due to scarcity of data concerning the effect of T3 on lipid metabolism. In this study, we report a series of fascinating experimental findings on how T3 affects lipid metabolism in differentiated 3T3-L1 preadipocytes. Treatment with T3 (25 μM), especially δ and γ isomers, inhibited the accumulation of triglyceride and lipid droplets in differentiated 3T3-L1 cells. This manifestation was supported by mRNA and protein expression of crucial lipid metabolism-related genes. The present study provides a novel set of data pertaining to the possibility of T3 as an anti-metabolic disorder agent.

Covering: 2010-2011. Previous review: Nat. Prod. Rep. 2010, 27, 1630-1680This review covers the literature on simple indole alkaloids and those with a non-rearranged monoterpenoid unit from the beginning of 2010 up to the end of 2011, which includes newly isolated alkaloids, structure determinations, total syntheses and biological activities.