Exploration of conjugated π-bridge units in N,N-bis(4-methoxyphenyl)naphthalen-2-amine derivative-based hole transporting materials for perovskite solar cell applications: a DFT and experimental investigation

DFT and experimental investigation was used for the material design on the core engineering in N,N-bis(4-methoxyphenyl)naphthalen-2-amine derivative-based hole transporting materials for perovskite solar cell applications.

Lanthanide DO3A-Complexes Bearing Peptide Substrates: The Effect of Peptidic Side Chains on Metal Coordination and Relaxivity

Two DO3A-type ligands conjugated to substrates of urokinase (L3) and caspase-3 (L4) via a propyl-amide linker were synthesized and their lanthanide(III) (Ln3+) complexes studied. A model compound without peptide substrate (L2) and an amine derivative ligand mimicking the state after enzymatic cleavage (L1) were also prepared. Proton Nuclear Magnetic Relaxation Dispersion (NMRD) profiles recorded on the gadolinium(III) (Gd3+) complexes, complemented with the assessment of hydration numbers via luminescence lifetime measurements on the Eu3+ analogues, allowed us to characterize the lanthanide coordination sphere in the chelates. These data suggest that the potential donor groups of the peptide side chains (carboxylate, amine) interfere in metal coordination, leading to non-hydrated LnL3 and LnL4 complexes. Nevertheless, GdL3 and GdL4 retain a relatively high relaxivity due to an important second-sphere contribution generated by the strongly hydrophilic peptide chain. Weak PARACEST effects are detected for the amine-derivative EuL1 and NdL1 chelates. Unfortunately, the GdL3 and GdL4 complexes are not significantly converted by the enzymes. The lack of enzymatic recognition of these complexes can likely be explained by the participation of donor groups from the peptide side chain in metal coordination.

Amine Derivative from the Aerial Part of Spilanthes acmella Murr. and their Alkaline Phosphatase Activity

Background: Spilanthes acmella Murr. is included in Asteraceae family which is used as a traditional remedy for tooth-aches, and originated from Africa, America, Borneo, India, Sri Lanka, Bangladesh, China, Japan, Thailand, and Indonesia. The present research aims to isolate the amine derivative from the ethyl acetate layer of this plant and to evaluate the isolated compounds of alkaline phosphatase activity as a sign of bone formation. Methods: The air-dried plants of Spilanthes acmella Murr. were extracted with methanol, then partitioned with n-hexane and ethyl acetate successively by using liquid-liquid extraction, and then the chromatographic techniques were repeated, such as silica gel, octadecyl silylated silica gel, and HPLC. The isolated compounds were determined by spectrometric analysis using ultraviolet, infrared, high-resolution electrospray ionization mass spectrometry, 1D and 2D NMR. Results: Benzenepropanoic acid, 4 hydroxy-2-oxo-3 piperidinyl ester (1), was isolated from the ethyl acetate layer of the whole plants of Spilanthes acmella Murr. together with dendranthemoside A (2), uridine (3), icariside B2 (4), chicoriin (5), dendranthemoside B (6), and ampelopsisionoside (7) from their butanol layer. Conclusion: An amine derivative, a benzenepropanoic acid that determined as 4 hydroxy-2-oxo-3 piperidinyl ester (1) was isolated and reported for the first time from the ethyl acetate layer of Spilanthes acmella naturally. All the isolated compounds from this plant stimulated alkaline phosphatase activity as a mark of bone formation up to 128%.

Experimental and theoretical investigations of four amine derivatives as effective corrosion inhibitors for mild steel in HCl medium

Four amine derivative compounds were synthesized and used as organic corrosion inhibitors.