Chemical Constituents of the Marine Sponge Aaptos aaptos (Schmidt, 1864) and Their Cytotoxic Activity

Seven compounds (1-7) were isolated from the marine sponge Aaptos aaptos living in the Vietnamese sea. Their structures were determined as 2 hours, 5 H,7 H,9 H-9 S-hydroxy-imidazo[1,5- α]pyridine-1,3-dione (1), 3-([9-methylhexadecyl]oxy)propane-1,2-diol 2, 2,3-dihydro-2,3-dioxoaaptamine (3), indol-3-aldehyde (4), methyl indole-3-carboxylate (5) 4-hydroxy-5-(indole-3-yl)−5-oxo-pentan-2-one (6), and thymidine (7) by extensive analysis of HR-ESI-MS, 1D, and 2D NMR spectral data, as well as by comparison of the spectral data with those reported in the literature. In addition, the absolute configuration of 1 was determined from the experimental ECD spectrum and comparison of this with the theoretical ECD calculations using the TDDFT method. Compounds 1 and 2 were isolated from nature for the first time. Compound 3 induced cytotoxic activity against SK-LU-1, MCF-7, HepG2, and SK-Mel-2 cell lines with IC50 values of 41.27 ± 2.63, 40.70 ± 2.65, 34.31 ± 3.43, and 36.63 ± 1.40 µM, respectively.

A theoretical study on the electronic structure and phosphorescence properties of two series of iridium(iii) complexes with a four-membered Ir–S–C–S chelating ring

The electronic structure and photophysical properties of two series of iridium(iii) complexes with a four-membered Ir–S–C–S chelating ring have been theoretically studied using the DFT and TDDFT method.

Formation of Cu3,4(TCA), making the TCA complex a highly selective probe for Cu2+ detection: a TDDFT study

The existing evidence for Cu3,4(TCA) complexes from FRET mechanism analysis of a self-assembled molecular probe by TDDFT method.

The effects of different heterocycles and solvents on the ESIPT mechanisms of three novel photoactive mono-formylated benzoxazole derivatives

The detailed effects of different heterocycles and solvents on the dynamical ESIPT mechanisms of three novel mono-formylated benzoxazole derivatives A–C in two different surroundings have been expounded by the TDDFT method at the B3LYP/TZVP level.