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Planar 1,2-naphthalocyanines present four different geometrical isomers of C_4h, C_2v, D_2h and C_s symmetries. In the case of magnesium complexes these four isomers have been isolated and characterized for the first time. The C_4h and C_s isomers of the magnesium complexes have been transformed in two steps into the corresponding lutetium mononaphthalocyanines 1,2-NcLuX.

3,5-Dicaffeoylquinic acid (diCQA) is a part of the chlorogenic acid group of compounds, largely isolated from food sources and possessing potent antioxidant activity. Only the trans–trans isomer exists in nature, however, abiotic stresses, such as UV-radiation, give rise to cis isomers. There have been no reports on the antioxidant activity of the cis isomers. The current study, performed using the B3LYP/6-311$+$G(d,p) method, is aimed at investigating and comparing the antioxidant properties of the geometrical isomers of 3,5-diCQA. The study is conducted by checking the molecules’ ability for two main radical scavenging mechanisms, hydrogen atom transfer (HAT) and electron transfer (ET). A separate DPPH assay experimental study performed in this study shows that all the geometrical isomers are potent radical scavengers. The lowest O$-$H bond dissociation enthalpy value (70.599 kcal/mol) corresponds to the trans–trans isomer and is comparable to that of gallic acid, a commercially available antioxidant. The lowest ionization potential value corresponds to the cis–cis isomer (149.54kcal/mol), indicating that it is best antioxidant, in terms of ET mechanism.