This review describes the contemporary development applications on scientific areas of acyclic and cyclic Schiff bases and their complexes with an emphasis on the author's contribution to the field. After a short historical introduction, this manuscript is divided into two main parts. In the first section, Schiff bases are reviewed for their biological activities including antibacterial, antifungal, antioxidant, cytotoxic, and enzymatic activities as well as their interaction with single-stranded-DNA which have shown remarkable activities in each region of research. The second part deals with the corrosion of metal and its alloys in corrosive environments and their organic inhibitors. The main section of this part is to investigate the different chemical structures for Schiff bases used in such aggressive solution to protect metals.Knowing the maximum corrosion efficiency or bioactivity of a specific chemical structure in a specific application environment is helpful for choosing the most appropriate compound. Scheme 2 Synthesis of complexes M(L 1 )PPh 3 -M(L 4 )PPh 3 . Scheme 3 Synthesis of Schiff base complexes (a-c). Scheme 4 Synthesis of imines (HL 1 -HL 4 ). Scheme 5 Structures of the ligands and the formation of complexes 1-3. This journal is Scheme 6 Structures of SBs (L 1 and L 2 ). Scheme 7 Synthesis of the copper complexes from bis(dithiocarbazate) ligands. Reagents and conditions: (a) CS 2 , KOH, EtOH, 0 C, 1 h; (b) CH 3 I or PhCH 2 Cl, EtOH, 0 C, 5 h; (c) for SMHDH 2 (2,5-hexanedione, EtOH, 79 C, 1 h), for SBHDH 2 (2,5-hexaedione, EtOH, 79 C, 5 min) and (d) for CuSMHD [Cu(OAC) 2 $H 2 O, MeOH, 65 C, 1 h], for CuSBHD [Cu(OAc) 2 , acetonitrile, r.t, 1 h]. Scheme 13 Synthetic pathway for the protection of target compounds 2, 3, 4, 5, 6 and 7. This journal is Scheme 14 Synthesis of copper complexes [Cu(L 1 ) 2 -Cu(L 3 ) 2 ]. Scheme 15 Synthesis of Schiff bases 1-5. Scheme 16 Synthesis of C6-Schiff bases of chitosan derivatives. Scheme 17 Synthesis of chitosan Schiff bases (ChBs). Scheme 18 Modification of chitosan-graft-polyacrylonitrile.
This journal isScheme 19 Schematic representation of ionic liquid-anchored chitosan Schiff bases and their metal complexes.
