Visible-Light-Catalyzed [3 + 1 + 2] Coupling Annulations for the Synthesis of Unsymmetrical Trisubstituted Amino-1,3,5-triazines.

A visible-light catalyzed [3 + 1 + 2] annulation for the synthesis of unsymmetrical trisubstituted amino-1,3,5-triazines from amidines, isothiocyanates, and 1,1,3,3-tetramethylguanidines has been developed. This method exhibits the advantages of easily available starting materials, insensitive to air and moisture, wide substrate scopes, high step economy, mild, metal- and ligand-free conditions, which has potential applications in the organic, medicinal, and material chemistry.

Photodriven Photocatalyst/Metal-Free Direct C-C/C-N Bond Formation: Synthesis of Indoles via EDA Complexes.

The photodriven direct C-C/C-N bond formation initiated by electron donor-acceptor (EDA) complexes for the synthesis of indoles has been accomplished via [3+2] annulations of secondary arylamines with alkynes using ICF as oxidants in the absence of any photocatalysts and metals. This green transformation exhibits the advantages of operational simplicity, good functional tolerances, and mild reaction conditions. The in situ generated EDA complexes derived from arylamines with alkynes were characterized by UV-vis absorption spectrometry and NMR titration experiments.

Visible-Light-Promoted Three-Component Coupling Annulation: Synthesis of 2-Iminothiazolidin-4-ones via in Situ Formed Electron Donor-Acceptor Complexes.

A novel and efficient three-component coupling annulation strategy for the synthesis of 2-iminothiazolidin-4-ones from amines, isothiocyanates, and alkyl acetylenedicarboxylates under visible-light irradiation conditions has been demonstrated. In this transformation, the in situ formed photoactive electron donor-acceptor (EDA) complexes facilitate the reaction and smoothly generate the corresponding products with a high adaptability under mild conditions. This protocol provides a cost-efficient and practical route to 2-iminothiazolidin-4-ones and promotes potential applications on the synthetic drugs.

TROP2 promotes cell proliferation and migration in osteosarcoma through PI3K/AKT signaling.

Human trophoblast cell surface antigen 2 (TROP2) has been noted to serve an important role in the proliferation and migration of various types of human cancers. However, the potential role and the molecular mechanisms of TROP2 in osteosarcoma (OS) remain largely unclear. In the present study, high expression of TROP2 in human OS tissues and cell lines was observed.

Direct Photocatalytic S-H Bond Cyanation with Green "CN" Source.

Herein we report a novel C-S bond cleavage and reconstruction strategy for the synthesis of thiocyanates through direct photocatalytic S-H bond cyanation from thiols and inorganic thiocyanate salts. In our strategy, the unprecedented example of cutting off C-S bond of SCN to deliver the green "CN" sources is demonstrated. This transformation features nontoxic and inexpensive "CN" sources, available starting materials, metal-/base-/ligand-/peroxide-free, high step economy and mild conditions.

Visible Light-Promoted Three-Component Tandem Annulation for the Synthesis of 2-Iminothiazolidin-4-ones.

Described is a visible light-promoted three-component tandem annulation of amines, aryl/alkyl isothiocyanates, and α-bromoesters to form 2-iminothiazolidin-4-ones in the absence of metal and photocatalyst at room temperature. This [1 + 2 + 2] cyclization strategy involves visible light-promoted C-S/C-N bond formation and features a powerful approach to the synthesis of 2-iminothiazolidin-4-ones with broad substrate scope, excellent functional group tolerance, mild reaction conditions, step-economy, and simple operation, which also has potential applications in the pharmaceutical industry. UV-vis spectroscopy indicates that an in situ-generated H-bonding electron donor-acceptor (EDA) complex probably acts as the photocatalyst, facilitating the reaction process.