Thiosemicarbazones of p-aminobenzoic acid (PABA) were synthesized and tested for their antimicrobial and anticancer activity. Hydroxamate derivatives 4a-4l were found to have better antimicrobial and anticancer activity than their acid counterpart. Compound 4d was found to have good antimicrobial activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Vibrio cholerae, and Bacillus subtilis with IC(50) value of about 1 µM. Compound 4f showed potent antifungal activity against Candida albicans (IC(50)  = 1.29 µM) and compound 4h showed potent anticancer activity (IC(50)  = 0.07 µM).

Isatin or 1H-indole-2, 3-dione is an indole derivative. Isatin is an important class of heterocyclic compounds. Recently, heterocyclic compounds analogues and their derivatives have attracted strong interest in medicinal chemistry due to their biological and pharmacological properties. The structure have offered a high value of diversity that is proven useful for the development of new medicinal drugs and improved potency,less toxicity and good pharmacological activity. Isatin has a wide varity of pharmacological activities such as an antimicrobial, anticancer, antiviral, anticonvulsant, anti-inflammatory and analgesic etc. The aim of this review is to provide the recent efforts of scinentists in pharmacological screening of isatin, importants and synthesis of isatin derivatives,pharmacological action of isatin and their biological activity.