**5. Schiff base biological activity**

Bacteria that display multiple antibiotic resistance [77] are closely linked to the rise in the mortality rate of infectious illnesses [78]. The main reason for this issue is the lack of efficient therapies. There is unquestionably an urgent medical need for the creation of new antibacterial drugs with inventive and more effective modes of action. Hence, Schiff bases called azomethines containing nitrogenous analogue of carbonyl compound changed by imine group are used. For antimicrobial activity, these bases produce excellent activity [79]. Aside from natural and synthetic molecules, biomolecules, sulfonamides, coumarins, aminothiazolyl, bromocoumarins, O-phthaldehyde, or 2-aminophenol, and 1, 2, 4-triazoles are other molecules that can be used as platforms to create Schiff bases for antibacterial activities [80].

As malaria is a disorder associated with severe health problems of public and globally its cases are increasing. Hence, various authors synthesized antimalarial Schiff base derivatives for prominent activity [81]. Also these bases have maximum activity for fungal infection due to its structure. In case of viral disorder, in the market there are numbers of drugs, but they are not fully active due to mutations in viruses. To overcome these problems, Schiff base derivatives are synthesized as an antiviral agent [82]. Different biological activities of Schiff bases are shown in **Table 2**.

### **6. Schiffs base abiological activity**

Schiff base possesses various medicinal activities. In addition to the same, they are now being used in diagnostics also. Some of the abioloical applications of Schiff's base are mentioned in this section.


**Table 1.** *Recently synthesized Schiff-base metal complex.*
