A novel approach for the one-pot synthesis of linear and angular fused quinazolinones

A binuclear aluminium complex as a single competent catalyst for efficient synthesis of urea, biuret, isourea, isothiourea, phosphorylguanidine, and quinazolinones

The synthesis and characterisation of two mononuclear aluminium alkyl complexes with the general composition [Al(Me)₂{Ph₂P(E)N(CH₂)₂N(CH₂CH₂)₂O}] (E = Se (2a); S (2b)), and two binuclear aluminium complexes, [Al(Me)₂{Ph₂P-(E)N(CH₂)₂N(CH₂CH₂)₂O}(AlMe₃)] (E = Se (3a) and S (3b)), are described. The binuclear aluminium alkyl complex 3a proved to be a proficient catalyst for the addition of simple nucleophiles to heterocumulenes, leading to the synthesis of a variety of products such as urea, biuret, isourea, isothiourea, phosphorylguanidine, and quinazolinone derivatives, in contrast to its mononuclear analogues. Complex 3a is the first example of a single competent catalyst, which is also low-cost and eco-friendly and derived from a main-group metal, under solvent-free conditions either at room temperature or mild temperatures. Complex 3a possessed a wide functional group tolerance including heteroatoms, yielding the corresponding insertion products in good quantities and with high selectivity.

Flexible Approach for the Synthesis of Annulated 4H-Pyrans Based on a Cu(I)-Catalyzed C-Allylation/O-Vinylation Reaction of Cyclic 1-Bromoallyl Tosylates with Cyclic and Acyclic 1,3-Dicarbonyls

The Cu(I)-catalyzed reaction between five-, six-, seven-, and eight-membered cyclic 1-bromoallyl tosylates and five- and six-membered cyclic 1,3-dicarbonyls in DMF at 80 °C using Cs₂CO₃ as a base and 2-picolinic acid as an additive selectively delivers a wide array of bisannulated 4H-pyrans in a single step with yields up to 92%. The transformations are considered to proceed as intermolecular C-allylations/intramolecular O-vinylations. With six-membered cyclic 1-bromoallyl tosylates and acyclic β-ketoesters as substrates, the corresponding 5,6,7,8-tetrahydro-4H-chromene-3-carboxylates are obtained with yields up to 59%.

Recent Advances in the Tandem Copper-Catalyzed Ullmann-Goldberg N-Arylation–Cyclization Strategies

N‒Aryl bond formation under copper catalysis has been playing a pivotal role and has been extensively used as a key step in the total syntheses of several therapeutic molecules. The...

Deciphering the key heterocyclic scaffolds in targeting microtubules, kinases and carbonic anhydrases for cancer drug development

Heterocyclic scaffolds are widely utilized for drug design by taking into account the molecular structure of therapeutic targets that are related to a broad spectrum of ailments, including tumors. Such compounds display various covalent and non-covalent interactions with the specific residues of the target proteins while causing their inhibition. There is a substantial number of heterocyclic compounds approved for cancer treatment, and these compounds function by interacting with different therapeutic targets involved in tumorogenesis. In this review, we trace and emphasize the privileged heterocyclic pharmacophores that have immense potency against several essential chemotherapeutic tumor targets: microtubules, kinases and carbonic anhydrases. Potent compounds currently undergoing pre-clinical and clinical studies have also been assessed for ascertaining the effective class of chemical scaffolds that have significant therapeutic potential against multiple malignancies. In addition, we also describe briefly the role of heterocyclic compounds in various chemotherapy regimens. The optimized molecular hybridization of delineated motifs may result in the discovery of more active anticancer therapeutics and circumvent the development of resistance by specific targets in the future.

Ru(II)/Ir(III)-Catalyzed C-H Bond Activation/Annulation of Cyclic Amides with 1,3-Diketone-2-diazo Compounds: Facile Access to 8H-Isoquinolino[1,2-b]quinazolin-8-ones and Phthalazino[2,3-a]cinnoline-8,13-diones

Efficient access to 8H-isoquinolino[1,2-b]quinazolin-8-ones and phthalazino[2,3-a]cinnoline-8,13-diones through cyclic amide-directed Ru(II)/Ir(III)-catalyzed C-H bond activation, has been developed. Consecutive C-H bond activation, carbene insertion, and condensation annulation processes were realized, affording 8H-isoquinolino[1,2-b]quinazolin-8-one and phthalazino[2,3-a]cinnoline-8,13-dione derivatives in good-to-excellent yields under mild conditions, with H₂O and N₂ being generated as the only byproducts.

Condensation of anthranilic acids with pyridines to furnish pyridoquinazolones via pyridine dearomatization

The unprecedented carbodiimide-mediated condensation between pyridines and anthranilic acids at room temperature has been developed for pyridoquinazolones.

A POCl3-mediated synthesis of substituted fused azoacridones derivatives

We provide an efficient approach to synthesize fused azoacridone derivatives, which showed broad substrate scope and good yields.

Copper-catalyzed aerobic oxidative C-H and C-C functionalization of 1-[2-(arylamino)aryl]ethanones leading to acridone derivatives

Efficient copper-catalyzed aerobic oxidative C-H and C-C functionalization of 1-[2-(arylamino)aryl]ethanones leading to acridones has been developed. The procedure involves cleavage of aromatic C-H and acetyl C-C bonds with intramolecular formation of a diarylketone bond. The protocol uses inexpensive Cu(O2CCF3)2 as catalyst, pyridine as additive, and economical and environmentally friendly oxygen as the oxidant, and the corresponding acridones with various functional groups were obtained in moderate to good yields.