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A new sensor based on Ethylbenzothiazolium-2-hydroxynaphthaldehyde conjugate-based fluorescent sensor, (E)-3-ethyl-2-(2-(2-hydroxynaphthalen-1-yl) vinyl) benzo[d]thiazol-3-ium iodide (SU-1) was designed and synthesized. The structure of SU-1 was confirmed by 1 H NMR, 13 C NMR, HRMS, and single crystal XRD spectral analysis. SU-1 displayed a colorimetric and fluorometric response in a DMSO:H 2 O (1:1,v/v) matrix, changing color from pale yellow to colorless visible to the naked eye, accompanied by a ∼ 120 nm red-shift in the absorption spectra upon CN - addition. This shift, due to formation of deprotonation followed by the nucleophilic attack on the benzothiazolium ring's double bond, disrupts π-conjugation, blocking intramolecular charge transfer within SU-1. However, competitive anions showed negligible interference while detecting CN - . The Limit of detection for CN - was determined to be 0.27 nM, significantly below the WHO's permissible CN - concentration in drinking water (1.9 μM). Job's plot analysis shows that the binding stoichiometry of SU-1 to CN - is a 1:1, with a stability constant (Ka) of 1.58 x 10 4 M -1 . The sensor demonstrated practical applications in environmental water samples and fluorescence imaging of intracellular CN - in CAD cell line., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

This study aims to prepare an ion-imprinted polymer (IIP) using copper sulfate as a template and potassium persulfate as an initiator to selectively adsorb copper ions (Cu 2+ ) from aqueous solutions and in an attempt to also test its applicability for removing strontium ions (Sr 2+ ). The prepared polymer was denoted by IIP-Cu. Various physical and chemical characterizations were performed for the prepared IIP-Cu. The scanning electron microscopy and transmission electron microscopy analyses confirmed the cavities formed after the removal of the template. It also indicated that the IIP-Cu had a rough and porous topology. The X-ray photoelectron spectroscopy confirmed the successful removal of the Cu template from IIP-Cu. The Brunauer-Emmet-Teller revealed that the surface area of IIP-Cu is as high as 152.3 m 2 /g while the pore radius is 8.51 nm. The effect of pH indicated that the maximum adsorption of Cu 2+ was achieved at pH 8 with 98.7%. Isotherm studies revealed that the adsorption of Cu 2+ was best explained using Langmuir models with a maximum adsorption capacity of 159 mg/g. The effect of temperature revealed that an increase in temperature had an adverse impact on Cu 2+ removal from the aqueous solution, which was further confirmed by thermodynamic studies. The negative value of standard enthalpy change (-4.641 kJ/mol) revealed that the adsorption of Cu 2+ onto IIP-Cu was exothermic. While the continuous increase in Gibbs free energy from -6776 kJ/mol to -8385 kJ/mol with the increase in temperature indicated that the adsorption process was spontaneous and feasible. Lastly, the positive value of the standard entropy change (0.023 J/mol.K) suggested that the Cu 2+ adsorption onto IIP-Cu had a good affinity at the solid-liquid surface. The efficiency of the prepared IIP-Cu was also tested by studying the adsorption capacity using Sr 2+ and real brine water. The results revealed that IIP-Cu was able to remove 63.57% of Sr 2+ at pH 8. While the adsorption studies revealed that the experiment was best described using the Langmuir model with a maximum adsorption capacity of 76.92 mg/g. Additionally, IIP-Cu was applied in a real brine sample, which consisted of various metal ions. The highest percentage of Cu 2+ removal was 90.6% and the lowest was 65.63% in 1:4 and 1:1 brine ratios, respectively. However, this study indicates the successful application of IIP-Cu in a real sample when it comes to the effective and efficient removal of Cu 2+ in a solution consisting of various competing ions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Colon cancer (CRC) is the second leading cause of death and the third most diagnosed cancer worldwide. Although curcumin (CUR) has demonstrated a potent anticancer activity, it is characterized by its poor solubility, low bioavailability, and instability. This study is a projection from a previous investigation where CUR and succinylated CUR (CUR.SA) were separately encapsulated in mannosylated-chitosan nanoparticles (CM-NPs) to form CUR-NPs and CUR.SA-NPs, respectively. Here, we aim to assess the anti-CRC activity of these two nanoformulations. Cytotoxicity studies using CCK-8 assay indicated that both CUR-NPs and CUR.SA-NPs have a dose and time-dependent toxicity towards CRC human cell-lines (HCT116 and SW480), and more cytotoxic compared to free CUR or CUR-SA in a time-dependent manner. A significant induction of early and late apoptosis in the CUR-NPs and CUR.SA-NPs treated CRC cell lines compared to untreated cells was observed. Western blotting analyses confirmed the induction of apoptosis through activation of Caspase signaling compared to untreated cells. Based on the physicochemical properties of CUR-NPs and CUR.SA-NPs along with the data from the in vitro studies, we may conclude these nanoparticle formulations hold very promising attributes, worthy of further investigations for its role in the management of CRC., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

Curcumin (CUR) manifests anti-colon cancer activity but suffers from low solubility, bioavailability, and instability, rendering it not as effective as its chemotherapeutic cousins. Here, we conjugate CUR to succinic anhydride (SA), (CUR.SA conjugate), subsequently formulated in mannose-conjugated chitosan nanoparticles (CUR-NPs and CUR.SA-NPs). Instrumental analyses confirmed formation of CUR.SA and mannosylated chitosan (CM) conjugates, with CUR.SA being less crystalline thus, more soluble. Average particle size of CUR-NPs and CUR.SA-NPs were 268 ± 6 nm and 342 ± 4.6 nm, with drug entrapment of 93.34 ± 0.40 % and 98.46 ± 0.06 % respectively. In vitro releases of CUR and CUR.SA from nanoparticles in pH 1.2 and 6.8 media were slow and sustained over 2 h and 72 h, respectively. The physical characteristics of the nanoparticles were unchanged over 3 weeks of storage. Thus, a successful CUR.SA conjugate has been developed, couriered in CM nanoparticles, with favorable attributes that warrant further anti-colon cancer studies, which is ongoing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Interest in developing selective and sensitive metal sensors for environmental, biological, and industrial applications is mounting. The goal of this work was to develop a sensitive and selective sensor for certain metal ions in solution. The goal was achieved via (i) preparing the sensor ((E)-2-((pyridine-3-ylimino)methyl)phenol) (3APS) using microwave radiation in a short time and high yield and (ii) performing spectrophotometric titrations for 3APS with several metal ions. 3APS, a Schiff base, was prepared in 5 min and in a high yield (95%) using microwave-assisted synthesis. The compound was characterized by FTIR, XRD, NMR, and elemental analysis. Spectrophotometric titration of 3APS was performed with Al(III), Ba(II), Cd(II), Co(II), Cu(II), Fe(III), Mn(II), Ni(II), and Zn(II). 3APS showed good abilities to detect Al(III) and Fe(III) ions fluorescently and Cu(II) ion colorimetrically. The L/M stoichiometric ratio was 2:1 for Cu(II) and 1:1 for Al(III) and Fe(III). Low detection limits (μg/L) of 324, 20, and 45 were achieved for Cu(II), Al(III), and Fe(III), respectively. The detection of aluminum was also demonstrated in antiperspirant deodorants, test strips, and applications in secret writing. 3APS showed high fluorescent selectivity for Al(III) and Fe(III) and colorimetric selectivity towards Cu(II) with detection limits lower than corresponding safe drinking water guidelines.

There is growing concern in the rise of colorectal cancer (CRC) cases globally, and with this rise is the presentation of drug resistance. Like other cancers, current treatment options are either invasive or manifest severe side effects. Thus, there is a move towards implementing safer treatment options. Curcumin (CUR), extracted from Curcuma longa, has received significant attention by scientists as possible alternative to chemotherapeutic agents. It is safe and effective against CRC and nontoxic in moderate concentrations. Crucially, it specifically modulates apoptotic effects on CRC. However, the use of CUR is limited by its low solubility and poor bioavailability in aqueous media. These limitations are surmountable through novel approaches, such as nanoencapsulation of CUR, which masks the physicochemical properties of CUR, thus potentiating its anti-CRC effects. Furthermore, chemical derivatization of CUR is another approach that can be used to address the above constraints. This review spans published work in the last two decades, with key findings employing either of the two approaches, in addition to a combined approach in managing CRC. The combined approach affords the possibility of better treatment outcomes but not widely investigated nor yet clinically implemented., (© 2022. The Author(s).)

The study aims to prepare a novel low-cost and environmentally friendly adsorbent by using date pits (DP) impregnated with cellulose nanocrystals (CNCs) and ionic liquid (IL), named IL-CNC@DP. The batch adsorption of lithium onto IL-CNC@DP and DP were studied at different pH values, initial lithium concentrations, and temperatures. The thermodynamics constants of the adsorption process showed that the IL-CNC@DP was exothermic, did not favor a high level of disorder, and spontaneous in nature. At pH 6, there is a significant increase in the removal efficiency where it increased to 90%. This also could be explained by the fact that electrostatic attraction forces and hydrogen bonding existed between the protonated Li + and the less protonated IL-CNC@DP adsorbent surface, which enhanced the percentage of Li + removal. A strong inter- and intra-hydrogen bonding (O-H) stretching absorption is seen at 3311 cm -1 that occurs in cellulose components. In conclusion, the IL-CNC@DP in comparison to the DP confirmed exceptional results proving that the modification enhanced the remediation of the Li + from water. Furthermore, the selectivity of IL-CNC@DP towards real groundwater samples isolated in Qatar depends upon the physicochemical characteristics of each element., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

The title compound, C 13 H 16 N 2 O 4 , crystallizes in the monoclinic centrosymmetric space group, P 2 1 / c , with four mol-ecules in the asymmetric unit, thus there is no crystallographically imposed symmetry and it is a racemic mixture. The structure consists of a six-membered unsaturated ring bound to a five-membered pyrrolidine-2,5-dione ring N-bound to a six-membered piperidine-2,6-dione ring and thus has the same basic skeleton as thalidomide, except for the six-membered unsaturated ring substituted for the aromatic ring. In the crystal, the mol-ecules are linked into inversion dimers by R 2 2 (8) hydrogen bonding involving the N-H group. In addition, there are bifurcated C-H⋯O inter-actions involving one of the O atoms on the pyrrolidine-2,5-dione with graph-set notation R 1 2 (5). These inter-actions along with C-H⋯O inter-actions involving one of the O atoms on the piperidine-2,6-dione ring link the mol-ecules into a complex three-dimensional array. There is pseudomerohedral twinning present which results from a 180° rotation about the [100] reciprocal lattice direction and with a twin law of 1 0 0 0 0 0 0 [BASF 0.044 (1)].

(E)-2-((benzo[ d ]thiazol-2-ylimino)methyl)-4-nitrophenol 1 and (E)-2-(((6-methoxybenzo[ d ]thiazol-2-yl)imino)methyl)-4-nitrophenol 2 were synthesized efficiently under microwave conditions. The structures were confirmed using IR, ¹H NMR, and 13 C NMR. UV-vis. Fluorescence investigations demonstrated that 1 and 2 are sensitive and selective sensors for detection of cyanide over all other anions SCN − , AcO − , N₃ − , H₂PO₄ − , H₂AsO₄ − , F − , Cl − , Br − , and I − in aqueous media. Cyanide induces colorimetric change from pale yellow to dark yellow and from transparent to pale yellow for 1 and 2, respectively. It enhances the absorption at wavelengths 385 nm and 425 nm of 1 and 385 nm and 435 nm of 2 . Acidic anions H₂PO₄ − and H₂AsO₄ − displayed significant interference with the interaction of cyanide and sensors 1 and 2 . Sensor 1 has lower detection limit (LDL) 1 × 10 −6 M, while 2 has LDL 1.35 × 10 −6 M.

In the title compound, C 12 H 9 NO 3 , the benzoate and furan rings are almost coplanar, making a dihedral angle of 11.68 (9)°. The twist angle between the -COO group and the benzene ring is only 2.79 (16)°. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming chains along [100]. The mol-ecules stack in a herringbone fashion and inversion-related chains are linked by offset π-π inter-actions [inter-centroid distance = 3.931 (1) Å], forming ribbons propagating along the a -axis direction.

The application of IR 786 perchlorate (IR-786) as a selective optical sensor for cyanide anion in both organic solution (acetonitrile (MeCN), 100%) and solvent-free solid surfaces was demonstrated. In MeCN, IR-786 was selective to two anions in the following order: CN(-) > OH(-). A significant change in the characteristic dark green color of IR-786 in MeCN to yellow was observed as a result of nucleophilic addition of CN(-) to the fluorophore, i.e., formation of IR 786-(CN), which was also verified by a blue shift in the 775 nm absorbance peak to 430 nm. A distinct green fluorescence emission from the IR-786-(CN) in MeCN was also observed, which demonstrated the selectivity of IR-786 towards CN(-) in MeCN. Fluorescence emission studies of IR-786 showed that the lower detection limit and the sensitivity of IR-786 for CN(-) in MeCN was 0.5 μM and 0.5 to 8 μM, respectively. The potential use of IR-786 as a solvent-free solid state sensor for the selective sensing and monitoring of CN(-) in the environment was also demonstrated. On solvent-free solid state surfaces, the sensitivity of the IR-786 to CN(-) in water samples was in the range of 50-300 μM with minimal interference by OH(-).

The title compound, C15H12N2O2S, crystallizes in the ortho-rhom-bic space group Pna21 , with two mol-ecules in the asymmetric unit (Z' = 2). Each mol-ecule consists of a 2-hy-droxy Schiff base moiety linked through a spacer to a 2-amino-benzo-thia-zole moiety. Each mol-ecule contains an intra-molecular hydrogen bond between the -OH group and imine N atom, forming a six-membered ring. The two independent molecules are linked by a pair of C-H⋯O hydrogen bonds, forming dimers with an R (2) 2(20) ring motif. These dimers are further lined into sheets in the ab plane by weak inter-molecular C-H⋯N inter-actions. The structure was refined as an inversion twin.

The title Schiff base compound, C15H15N3O3, crystallizes with two mol-ecules (A and B) in the asymmetric unit. Each mol-ecule adopts an E conformation around the C= N imine bond. The two mol-ecules have minor differences in their conformations. In mol-ecule A, the dihedral angle between the nitro group and its benzene ring is 2.1 (2)° and that between the two benzene rings is 0.88 (7)°, while the corresponding angles for mol-ecule B are 5.7 (1) and 2.45 (6)°, respectively. In each mol-ecule, there is an intra-molecular O-H⋯N hydrogen bond. In the crystal, inversion-related mol-ecules are linked via O-H⋯O hydrogen bonds forming A-A and B-B dimers. These dimers are linked via C-H⋯O hydrogen bonds involving the nitro O atoms, forming A-A-A and B-B-B slabs that lie parallel to one another and to (010).

In the title compound, C12H10N2O4, the furan-2-ylmethyl group is disordered over two sets of sites, with refined occupancies of 0.858 (3) and 0.143 (3). In the major component of disorder, the dihedral angle between the furan and benzene rings is 63.1 (2)° and for the minor component this value is 67.9 (6)°. The planes of the nitro group and the attached benzene ring form a dihedral angle of 4.34 (17)°. In the crystal, inversion-related mol-ecules are linked by two pairs of weak C-H⋯O inter-actions, one involving the nitro group and the other involving the O-H group as an acceptor. As a result of these associations, ribbons are formed along [120]. A strong intra-molecular O-H⋯N hydrogen bond is observed.

In the title crystal structure, C(12)H(22)NOSi(+)·Cl(-), anions and cations are linked via O-H⋯Cl, N-H⋯Cl and N-H⋯O hydrogen bonds to form a two-dimensional network parallel to (101). Within the hydrogen-bonded network, R(4) (2)(22) ring motifs are stacked along [010].

The title compound, C(12)H(22)NSi(+)·Cl(-), contains two formula units in the asymmetric unit and is a hydro-chloride salt in which the amine N atom is protonated and the NH(3) (+) group forms hydrogen bonds with the Cl(-) anion, forming a ribbon in the c-axis direction.

In the title compound, C(17)H(24)NO(2) (+)·Br(-)·H(2)O, the pentyl group chain in the cation extends nearly perpendicular [N-C-C-C = -64.4 (3)°] to the mean plane of the indole ring with the carboxyl end group twisted such that the dihedral angle between the mean planes of the indole and carb-oxy groups measures 43.2 (4)°. Both ions in the salt form inter-molecular hydrogen bonds (O-H⋯Br and O-H⋯O) with the water mol-ecule. As a result of the Br⋯H-O-H⋯Br inter-actions, a zigzag chain is formed in the c-axis direction. The crystal packing is influenced by the collective action of the O-H⋯O and O-H⋯Br inter-molecular inter-actions as well as π-π stacking inter-molecular inter-actions between adjacent benzyl rings of the indole group [centroid-centroid distance = 3.721 (13) Å] and inter-molecular C-H⋯π inter-actions between a methyl hydrogen and the benzyl ring of the indole group. The O-H⋯Br inter-actions form a distorted tetra-hedral array about the central Br atom. A MOPAC AM1 calculation provides support to these observations.

In the title mol-ecule, C(12)H(11)N(3)O(2), the dihedral angle between the mean planes of the naphthalene and carboxamide groups is 28.9 (8)°. The hydrazine N atoms are twisted slightly out of the plane of the carboxamide group [C-C-N-N torsion angle = -175.06 (13)°]. The crystal packing is influenced by N-H⋯O hydrogen bonding which includes a bifurcated hydrogen bond between the amide N atom and nearby carboxyl and hydroxyl O atoms. A second bifurcated hydrogen bond occurs between the hydroxyl O atom and nearby amide (inter-molecular) and hydrazine (intra-molecular) N atoms. As a result, mol-ecules are linked into a co-operative hydrogen-bonded network of infinite one-dimensional O-H⋯O-H⋯O-H chains along the (101) plane of the unit cell in a zigzag pattern, the dihedral angle between the mean planes of the naphthalene groups of adjacent mol-ecules in the chain being 86.9 (2)°. A MOPAC PM3 calculation provides support to these observations.

In the title mol-ecule, C(13)H(10)N(2)O(4), the dihedral angle between the mean planes of the benzene and phenolate rings is 21.6 (4)°. The nitro O atoms are twisted slightly out of the plane of the ring to which the nitro group is attached [dihedral angle 8.4 (3)°]. The amine group forms an intra-molecular hydrogen bond with both nearby O atoms. An extended π delocalization throughout the entire mol-ecule exists producing a zwitterionic effect in this region of the mol-ecule. The shortened C-O bond [1.2997 (15) Å] in concert with the slightly longer C-OH bond [1.3310 (16) Å] provide evidence for this effect. The crystal packing is influenced by strong inter-molecular O-H⋯O hydrogen bonding. As a result, mol-ecules are linked into an infinite zigzag chain running along the b axis. A MOPAC PM3 calculation provides support to these observations.

The title mol-ecule, C(11)H(12)N(2)O(4), consists of a 3-aza-bicyclo-[3.2.0]heptane group containing a nearly planar cyclo-butane ring (r.m.s. deviation of fitted atoms is 0.0609 Å), fused to a pyrrolidine ring, bonded to a 2,6-dioxopiperidine ring at the 3-position. The angle between the mean planes of the cyclo-butane and fused pyrrolidine ring is 67.6 (6)°. The dihedral angles between the mean planes of the pyrrolidine and cyclo-butane rings and the dioxopiperidine ring are 73.9 (2) and 62.4 (4)°, respectively. The pyrrolidine and dioxopiperidine rings are twisted about the 3-yl group [torsion angles = -55.0 (1) and 115.0 (1)°] in a nearly perpendicular manner. Crystal packing is influenced by extensive inter-molecular C-H⋯O and N-H⋯O inter-actions between all four carbonyl O atoms and H atoms from the cyclo-butane and dioxopiperidine rings, as well as between the N atom and an H atom from the cyclo-butane ring. In addition, weak π-ring interactions also occur between H atoms from the cyclobutane ring and the five-membered pyrrolidine ring. As a result, mol-ecules are linked into infinite chains diagonally along the [101] plane of the unit cell in an alternate inverted pattern.

The title mol-ecule, C(13)H(9)N(3)O(6), consists of a 2-hydr-oxy-5-nitro-phenyl-iminio group and a 4-nitro-phenolate group bonded to a methyl-ene C atom with both of the planar six-membered rings nearly in the plane of the mol-ecule [dihedral angle = 1.3 (4)°]. Each of the nitro O atoms is twisted slightly out of the plane of the mol-ecule. The amine group forms an intra-molecular hydrogen bond with both nearby O atoms, each of which has partial occupancy of attached H atoms [0.36 (3) and 0.64 (3)]. An extended π-delocalization throughout the entire mol-ecule exists producing a zwitterionic effect in this region of the mol-ecule. The shortened phenolate C-O bond [1.2749 (19)°], in concert with the slightly longer phenol C-O bond [1.3316 (19) Å], provides evidence for this effect. The crystal packing is influenced by extensive strong inter-molecular O-H⋯O hydrogen bonding between the depicted phenolate and hydr-oxy O atoms and their respective H atoms within the π-delocalized region of the mol-ecule. As a result, mol-ecules are linked into an infinite polymeric chain diagonally along the [110] plane of the unit cell in an alternate inverted pattern. A MOPAC AM1 calculation provides support for these observations.

The title compound, C(33)H(34)O(4)Si, is a dioxasilepine compound, an effective chiral dopant for the determination of high helical twisting powers in liquid crystals. Its structure consists of a five-membered dioxolo ring fused to a seven-membered dioxasilepine ring which contains two sets of phenyl rings in a twisted butterfly shape attached to the two Csp(3) atoms in the ring opposite each other. Two methyl groups are attached to the Si atom in the ring and two additional methyl groups are attached to the Csp(3) atom in the dioxolo ring (one of which is disordered) and which lies in an envelope pattern. The dihedral angles between the mean planes of the phenyl ring pairs are 85.9 (2) and 83.5 (1)°. The dihedral angles between the mean planes of the dioxolo ring and the two pairs of butterfly shaped phenyl rings are 46.2 (1), 67.7 (1), 35.6 (7) and 83.5 (1)°.

Unsubstituted cyclic imides were synthesized from a series of cyclic anhydrides, hydroxylamine hydrochloride (NH2OH.HCl), and 4-N,N-dimethylamino-pyridine (DMAP, base catalyst) under microwave irradiation in monomode and multimode microwaves. This novel microwave synthesis produced high yields of the unsubstituted cyclic imides for both the monomode (61 - 81%) and multimode (84 - 97%) microwaves.

Efficient syntheses of (Z,E)-5,7-dodecadienol, a pheromone component of the Siberian moth, Dendrolimus superans sibiricus, and (E,Z)-10,12-hexadecadienol, a pheromone component of various Lepidoptera pheromones, were accomplished by cis reduction of the corresponding enynols with activated zinc. The most energetic reagent was zinc galvanized with copper and silver (Zn/Cu/Ag) that achieved rapid and high-yield reduction in methanol-water. The stereoselectivity of semi-hydrogenation was > or =98%. A process whereby zinc dust was continuously activated throughout the reduction with an acid was also satisfactory (95-98% cis). Field evaluation of the 1:1 mixture of (Z,E)-5,7-dodecadienol and (Z,E)-5,7-dodecadienal with the Siberian moth in Russia showed that the rubber septa pretreated with compound and stored at -80 degrees C were as effective as freshly treated septa. Moth responses to septa aged in open air indicated that lure effectiveness declined significantly after 2 weeks of aging. Thus, if rubber septa are used as pheromone dispensers in Siberian moth traps monitoring, they should be replaced biweekly with fresh septa for optimal trap effectiveness.