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A new family of 16‐membered macrocycles comprising two indole (In) and two quinoline (Q) units, coined In2Q2, was synthesized. Each unit is diagonally located and concatenated in a head‐to‐tail fashion, furnishing a non‐flat saddle‐shaped architecture with C2 symmetry. The synthetic protocol utilizing macrocyclic diamide as a pivotal precursor allowed us to access a series of In2Q2 derivatives bearing various substituents on the periphery. The In2Q2 derivatives and their Zn2+ complexes were emissive in both solution phase and solid state. While the entire architecture of In2Q2 is similar to that of quinoline tetramer TEtraQuinoline, a couple of contrasting physicochemical properties were revealed. [ABSTRACT FROM AUTHOR]

The B3NO2 six‐membered heterocycle (1,3‐dioxa‐5‐aza‐2,4,6‐triborinane=DATB), comprising three different non‐carbon period 2 elements, has been recently demonstrated to be a powerful catalyst for dehydrative condensation of carboxylic acids and amines. The tedious synthesis of DATB, however, has significantly diminished its utility as a catalyst, and thus the inherent chemical properties of the ring system have remained virtually unexplored. Here, a general and facile synthetic strategy that harnesses a pyrimidine‐containing scaffold for the reliable installation of boron atoms is disclosed, giving rise to a series of Pym‐DATBs from inexpensive materials in a modular fashion. The identification of a soluble Pym‐DATB derivative allowed for the investigation of the dynamic nature of the B3NO2 ring system, revealing differential ring‐closing and ‐opening behaviors depending on the medium. Readily accessible Pym‐DATBs proved their utility as efficient catalysts for dehydrative amidation with broad substrate scope and functional‐group tolerance, offering a general and practical catalytic alternative to reagent‐driven amidation. A general and facile synthetic strategy that uses a pyrimidine‐containing scaffold for the reliable installation of boron atoms is disclosed. This strategy gave rise to a series of B3NO2 heterocycles Pym‐DATBs (DATB=1,3‐dioxa‐5‐aza‐2,4,6‐triborinane) from inexpensive materials in a modular fashion. The dynamic nature of the B3NO2 ring system was investigated for a soluble derivative and Pym‐DATBs proved their utility as efficient catalysts for dehydrative amidation. [ABSTRACT FROM AUTHOR]

An α-N3 7-azaindoline amide serves as a latent enolate to directly engage in an asymmetric Mannich-type reaction with N-thiophosphinoyl imines by the action of a cooperative catalyst. The thus-obtained highly enantioenriched anti-adduct was transformed into β-amino-α-azido acid in high yield by simple acidic treatment. [ABSTRACT FROM AUTHOR]

An enantioselective total synthesis of thuggacin B, a natural product exhibiting antibiotic activity against Mycobacterium tuberculosis, is described. Asymmetric direct aldol reactions promoted by Cu and Zn catalysts play a pivotal role in constructing four stereogenic centers. The use of direct aldol reactions as the initial steps for the synthesis of two key fragments allowed the construction of the other stereogenic centers through chirality transfer. [ABSTRACT FROM AUTHOR]