Benzazoles, such as benzoxazoles and benzothiazoles, are compounds with important biological and pharmacological activities and important intermediaries in synthesis. This report presents the synthesis of a butanamide derived from linking 5-chloro-2-aminobenzoxazole and 2-aminobenzothiazole via 4-chlorobutanoyl chloride. The corresponding compound N-(benzothiazol-2-yl)-4-((5-chlorobenzoxazol-2-yl)aminobutanamide was obtained 76 % yield global using accessible starting materials and methodology in two reaction steps. Furthermore, we made docking studies of this compound on 3-TOP protein to explore its potential as an antidiabetic agent.

The synthesis of the presented benzo[d]thiazol-2-amine derivatives was performed by condensing-(4-chlorobenzylidene) benzo[d]thiazol-2-amine with a number of substituted phenols in the presence of potassium iodide and anhydrous potassium carbonate in dry acetone. IR spectroscopy, 1HNMRspectroscopy and spectroscopy methods were used to characterize the structural properties of newly synthesized derivatives. In order to observe the attributes of drug-like candidates of these derivatives, the number of their molecular properties was estimated. Benzo[d]thiazol-2-amine derivatives were molecularly docked with selective enzymes COX-1 and COX-2. Findings suggested that Compounds G3, G4, G6, G8 and G11 possess higher binding affinity than diclofenac sodium, when docking was performed with enzyme COX-1. Compounds G1, G3, G6, G8and G10 showed lower binding affinity than Indomethacin when docking performed with enzyme COX-2.In vitro evaluation of the COX-1 and COX-2 enzyme inhibitory activities were performed for synthesized compounds. Compounds 10 and 11 exhibited significant COX-1 and COX- enzyme inhibitory action with IC50 values of 5.0 and 10 µM, respectively. Using the hot plate method and the carrageenan-induced rat paw edema model, the synthesized compounds were screened for their biological activities, including analgesic and anti-inflammatory activities. The highest analgesic action was exhibited by derivative G11and the compound G10 showed the highest anti-inflammatory response.

It is known that eumelanin (EM) is photoprotective while pheomelanin (PM) is phototoxic. A recent study using a mouse model demonstrated that PM produces reactive oxygen species (ROS) that cause DNA damage and eventually lead to melanomagenesis. A biochemical study showed that PM possesses a pro-oxidant activity. PM consists of benzothiazine (BT) and benzothiazole (BZ) moieties, the former being transformed to the latter by heat or light. In this study, we compared the effects of ultraviolet A (UVA) irradiation using synthetic PMs with different BT to BZ ratios and using various coat color mouse hairs. We found that UVA irradiation of BZ-PM increased glutathione (GSH) consumption and generated more H₂O₂ than UVA irradiation of BT-PM. Non-irradiated controls did not exhibit strong pro-oxidant activities. Upon UVA irradiation, yellow mouse hairs oxidized GSH and produced H₂O₂ faster than black or albino mouse hairs. Next, to examine the mechanism of the pro-oxidant activity of BT-PM and BZ-PM, we examined the pro-oxidant activities of 7-(2-amino-2-carboxyethyl)-dihydro-1,4-benzothiazine-3-carboxylic acid (DHBTCA) and 6-(2-amino-2-carboxyethyl)-4-hydroxybenzothiazole (BZ-AA) as BT and BZ monomers, respectively. Their pro-oxidant activities were similar, but a large difference was seen in the effects of ROS scavengers, which suggests that the redox reactions may proceed via singlet oxygen in BZ-AA and via superoxide anions in DHBTCA. These results show that UVA enhances the pro-oxidant activity of PM, in particular BZ-PM.