A survey of isatin hybrids and their biological properties

Abstract

The emergence of diverse infections worldwide, which is a serious global threat to human existence, necessitates the urgent development of novel therapeutic candidates that can combat these diseases with efficacy. Molecular hybridization has been established as an efficient technique in designing bioactive molecules capable of fighting infections. Isatin, a core nucleus of an array of compounds with diverse biological properties can be modified at different positions leading to the creation of novel drug targets, is an active area of medicinal chemistry. This review containing published articles from 2005 to 2022 highlights isatin hybrids which have been synthesized and reported in the literature alongside a discussion on their biological properties. The enriched structure-activity relationship studies discussed provides insights for the rational design of novel isatin hybrids with tailored biological properties as effective therapeutic candidates inspired by nature.

Keywords: Biological properties; Isatin hybrids; Molecular hybridization; Pharmacophore; Structure–activity relationship.

Fig. 1

The various possible modification positions on the isatin scaffold [12]

Fig. 2

Distribution of isatin hybrids

Fig. 3

Chemical structures of isatin-azole hybrids

Fig. 4

Chemical structures of isatin-furan hybrids

Fig. 5

Chemical structures of isatin-thiophene hybrids

Fig. 6

Chemical structures of isatin-indole hybrids

Fig. 7

Chemical structures of isatin-fluoroquinolone hybrids

Fig. 8

Chemical structures of isatin-sulfonamide hybrids

Fig. 9

Chemical structures of isatin-pyridine hybrids

Fig. 10

Chemical structures of isatin-chalcone hybrids

Fig. 11

Chemical structures of isatin-quinazoline hybrids

Fig. 12

Chemical structures of isatin-phthalazine hybrids

Fig. 13

Chemical structures of isatin-hydrazide hybrids

Fig. 14

Chemical structures of isatin-thiosemicarbazone hybrids

Fig. 15

Chemical structures of isatin-oxime hybrids

Fig. 16

Chemical structures of isatin-nitrone hybrids

Fig. 17

Chemical structure of an isatin-piperazine hybrid

Fig. 18

Chemical structures of isatin-uracil hybrids

Fig. 19

Chemical structures of isatin-coumarin hybrids

Fig. 20

Chemical structures of isatin-thiolactone hybrids

Fig. 21

Chemical structures of isatin-pyrimidine hybrids

Fig. 22

Chemical structures of isatin-quinoline hybrids

Fig. 23

Chemical structures of isatin-thioacetazone hybrids

Fig. 24

Chemical structures of other isatin hybrids