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A pyrido‐pyrimidinone heterocycle derived pH‐activated, hydrazone based molecular switch and its switching mechanism are reported here. The introduction of a new conjugated π electronic framework (enone part in the molecule) allowed the system to undergo hydrazone‐azo tautomerization, followed by E‐Z isomerization through rotation around the partial C−N single bond. Under acidic pH, protonation took place selectively on pyrimidinone nitrogen, and that turned the molecule to the corresponding ZH+ configuration. On the other hand, addition of triethylamine in the same solution reverted the molecule back to its original E‐configuration. Extensive proton‐NMR, and detailed X‐ray crystallography coupled with UV‐vis spectroscopy were carried out to establish the switching phenomena. Theoretical DFT calculations leading to free energy diagrams, transition states, and intermediates shed light on the mechanism behind the switching phenomenon. [ABSTRACT FROM AUTHOR]

Late‐stage functionalization of indoles can be a valuable strategy for modifying different existing indolyl‐drugs and natural products to get their new analogues. In this study, we report the photoredox‐metal catalyzed decarboxylative arylation strategy of indole‐3‐acetic acids with aryl halides. Here, photoredox‐catalysis was synergistically merged with nickel‐catalysis for the synthesis of biologically important 3‐benzyl indoles with good functional group tolerance. The merit of this methodology is demonstrated by the synthesis of amino acid derived substrates 3 p, 3 v and 3 x. [ABSTRACT FROM AUTHOR]

An environmentally benign, efficient, practically applicable and C(sp3)−H functionalization of primary amines for the synthesis of highly substituted oxazoles from easily available internal alkynes was developed. This synthesis is toxic chemicals, transition‐metal free as well as mild and regioselective. This one‐pot methodology with broad substrate scope unlocks a green avenue for the synthesis of highly functionalized oxazole derivatives with excellent yields. [ABSTRACT FROM AUTHOR]

Research has been conducted on the acetates derived from the Baylis-Hillman reaction's adducts. Results indicate that these acetates react with amines in the presence of palladium(0) catalyst and produce alpha-dehydro-beta-amino esters.

This article, titled "Front Cover Picture: Ru(II) Catalyzed Oxidative Dehydrogenative Annulation and Spirocyclization of Isoquinolones with N-Substituted Maleimides," discusses the pursuit of scientific discovery and the symbolism of perseverance and dedication in the ancient Indian quest for spiritual liberation. The authors express gratitude to Dipomita Banerji for editing the cover art picture. The details of the research can be found in the Research Article by Kaushik Seal and Biswadip Banerji. [Extracted from the article]

The total syntheses of five palmerolide A stereoisomers and the revised [ent-(19-epi-20-epi-1) structures are described. The Homer-Wadsworth-Emmons olefination and the Yamaguchi lactonization are examined and are successful as a means to construct the palmerolide macrocycle.

Here in we report, rhodium(III)‐catalyzed decarboxylative acylation of arenes using α‐oxocarboxylic acids as acyl surrogate. In this strategy, O–NHAc group act as an autocleavable oxidizing directing group (ODGauto), thus giving rise to ortho‐acylated phenols in moderate to good yields. Mechanistic studies provided strong support for a kinetically relevant C–H bond activation. According to the best of our knowledge, this is the first report of Rhodium catalyzed decarboxylative acylation. [ABSTRACT FROM AUTHOR]

A 'green' methodology for the convenient synthesis of specific regioisomers of polysubstituted oxazoles through iodine catalyzed, water‐mediated, aerobic oxidative C(sp3)−H functionalization of primary amines has been developed. This mild and regioselective domino procedure does not require toxic peroxides, transition metals and organic solvents. The versatility of this methodology was demonstrated by preparing a natural product, texaline. It is also scalable and has a wide substrate scope. This methodology opens up a simple avenue for the synthesis of polyarylated oxazoles from various readily available amines as well as 1,2‐diketones and acyloins (α‐hydroxyl ketones) in moderate to excellent yields. Furthermore, these highly substituted oxazole molecules showed excellent fluorescence properties and thus have enormous potential to be a new type of fluorescent probe for use in medicinal applications and materials science. Green fields: An environmentally benign methodology was developed for the synthesis of polysubstituted oxazoles through an iodine‐catalyzed oxidative cyclization in water. The antimycobacterial natural product texaline was synthesized by using this protocol. These polyarylated oxazoles were prepared from readily available starting materials and the reaction can also be performed on gram scale. Some of the oxazole moieties showed good fluorescence response in solution as well as solid state. [ABSTRACT FROM AUTHOR]