Copper has toxic effects in fish, whereas the cyanobacterium Spirulina reportedly has protective effects against metal toxicity in various animal species. The current study, therefore, aimed to investigate the prophylactic role of Spirulina platensis against the effects of copper sulfate (CuSO₄) and copper oxide nanoparticles (CuO-NPs) in Nile tilapia (Oreochromis niloticus). Biochemical, antioxidant, erthyron profile and histopathological endpoints were assessed after for 15 days of exposure in five separate treatment groups: (1) fish pre-fed the normal diet (control), (2) fish pre-fed the normal diet and exposed to 15 mg/L of CuSO₄, (3) fish pre-fed the normal diet augmented with 0.25% Spirulina and exposed to 15 mg/L of CuSO₄, (4) fish pre-fed the normal diet and exposed to 15 mg/L of CuO-NPs, and (5) fish pre-fed the normal diet augmented with 0.25% Spirulina and exposed to 15 mg/L CuO-NPs. Exposure to CuSO₄ or CuO-NPs significantly increased superoxide dismutase and catalase activities in fish, as well as serum total protein, glucose, aspartate aminotransferase, alanine aminotransferase, creatinine, and uric acid concentrations. In contrast, most hematological indices in fish significantly decreased after CuSO₄ or CuO-NPs exposure. Moreover, CuSO₄ and CuO-NPs caused a significant increase in the percentage of poikilocytosis and nuclear abnormalities of red blood cells, as well as histopathological changes in the brain, liver, intestine, and kidneys. Importantly, Spirulina supplementation mitigated against physiological disruption caused by CuSO₄ or CuO-NPs.

Due to the sensitivity for interchanging color by exposure to UV light, designing of fuorescent textiles is highly demanded to be employed in camping, military and sensing purposes. Aromatic compounds containing tetrahydroisoquinoline are known with their biological and medicinal activity, but they are not applied as fuorescent materials. Therefore, the present study focuses on synthesis of tetrahydrothienoisoquinoline derivatives and their application in textile technology to obtain fuorescent cotton fabrics. Four tetrahydrothienoisoquinoline derivatives were synthesized in three steps, starting from 2,4-diacetyl-5-hydroxy-5-methyl-3-(4-methoxyphenyl)cyclohexanone. The chemical structures ofthe synthesized tetrahydrothienoisoquinoline derivatives (Ar1-Ph, Ar2-Ph-Cl, Ar3-Ph-CH3 and Ar4-PhOCH3) were confrmed by infrared spectra, 1 HNMR and 13CNMR. The yields and melting points were both measured for all the synthesized compounds. The tetrahydrothienoisoquinoline derivatives were applied onto the cotton fabrics to obtain Ar1-Ph@ cotton, Ar2-Ph-Cl@cotton, Ar3-Ph-CH3@cotton and Ar4-Ph-OCH3@cotton fabrics. All modifed cotton fabrics were exhibited by green emission under UV lamp (325  nm). The excited modifed cotton fabrics showed an intense fuorescence emission peak at 444–467  nm, related to the implemented compounds. The intensity of the fuorescence peak followed the order of Ar1-Ph@cotton>Ar3-Ph-CH3@ cotton≥ Ar4-Ph-OCH3@cotton>> Ar2-Ph-Cl@cotton. The estimated quantum yield (QY) were 68.79%, 23.15%, 13.83% and 13.38%, for Ar1-Ph, Ar2-Ph-Cl, Ar3-Ph-CH3 and Ar4-Ph-OCH3, respectively. Due to the water insoluble character of tetrahydrothienoisoquinoline derivatives, the modifed fabrics showed quite good durability, as the the quantum yields were marginally diminished by only 10.1 – 12.3%, after 5 washings. The prepared tetrahydrothienoisoquinoline derivatives succeeded for obtaining durable fuorescent textiles, and could be further applied in advanced purposes including technical textiles, sensors/biosensors, smart labeling and anti-counterfeiting purposes.

The starting compounds 7-acetyl-8-aryl-4-cyano1,6-dimethyl-6-hydroxy-5,6,7,8-tetrahydroisoquinoline(2H)-3-thiones 3a,b were synthesized and reacted with some N-aryl-2- chloroacetamides 4a−e in the presence of sodium acetate to produce 7-acetyl-8-aryl-3-(N-arylcarbamoylmethylsulfanyl)-4- cyano-1,6-dimethyl-6-hydroxy-5,6,7,8-tetrahydroisoquinolines 5a− g. Upon heating in ethanol containing sodium ethoxide, they underwent intramolecular Thorpe−Zeigler cyclization, affording the corresponding 7-acetyl-1-amino-6-aryl-2-(N-arylcarbamoyl)- 5,8-dimethyl-8-hydroxy-6,7,8,9-tetrahydrothieno[2,3-c]- isoquinolines 6a−g. Compounds 6c,g,f were converted into the corresponding 1−(1-pyrrolyl) derivatives 7a−c by heating with 2,5-dimethoxytetrahydrofuran in glacial acetic acid. Structures of all synthesized compounds were characterized by elemental and spectral analyses. Also, the crystal structure of compounds 5a was determined by X-ray diffraction analysis.