Synthesis and Cytotoxicity in Vitro of N‐Aryl‐4‐(tert‐butyl)‐5‐(1H‐1,2,4‐triazol‐1‐yl)thiazol‐2‐amine

A series of novel N‐aryl‐4‐(tert‐butyl)‐5‐(1H‐1,2,4‐triazol‐1‐yl)thiazol‐2‐amines synthesized in a green way. H₂O₂‐NaBr Brominating circulatory system was used in the synthesis of the key intermediate in a mild condition. All of the target compounds were confirmed by ¹H NMR and elemental analysis and tested for their cytotoxicity against two different human cancer cell lines. The cytotoxicity assay revealed that some of the title compounds showed moderate to strong cytotoxic activities. Compound 2i was the most potent compound with the IC₅₀ values of 9 μM against Hela cells and 15 μM against Bel–7402 cells, respectively.     

Et3N‐Prompted Efficient Synthesis of Anthracenyl Pyrazolines and Their Cytotoxicity Evaluation against Cancer Cell Lines

A series of anthracenyl pyrazoline derivatives ( 3a – o ) were synthesized with an aim to evaluate their in vitro anticancer activities. Anthracenyl pyrazoline compounds were prepared by the reaction between various anthracenyl chalcones ( 1a – o ) and hydrazine hydrate ( 2 ). The reactions were carried out under reflux in the presence of triethylamine and ethanol for 24 h, and the obtained yields were from good to excellent (90–97%). The structure of each compound is well characterized by IR, ¹H‐NMR, ¹³C‐NMR, elemental analyses, and mass spectroscopic technics, and the molecular structures of compounds 3d and 3e were solved by single‐crystal X‐ray crystallographic methods. The newly synthesized compounds ( 3a – o ) were evaluated for their in vitro cytotoxic studies against four human cancer cell lines MCF‐7 (breast cancer cell lines), SK‐N‐SH (neuroblastoma cancer cell lines), HeLa (cervical cancer cell lines), and HepG2 (liver cancer cell lines), and the screening results show strong cytotoxic effects for most of the synthesized compounds against the three cell lines except SK‐N‐SH cells. Notably, compounds 3a , 3j , 3l , 3m , 3n , and 3o showed a highly potential activity against HeLa cells (IC₅₀: 0.22, 0.3, 0.3, 0.10, 0.25, and 0.25 μM), while compounds 3i , 3k , 3l , and 3m showed a significant cytotoxic activity in HepG2 cells (IC₅₀: 0.22, 0.44, 0.40, and 0.22 μM), whereas compounds 3a , 3b , 3d , and 3e exhibit a promising cytotoxicity against MCF‐7 cells (IC₅₀: 0.73, 0.495, 0.493, and 0.66 μM).     

Synthesis and Cytotoxic Evaluation of Some 4‐Anilinofuro[2,3‐b]quinoline Derivatives

Some 4‐anilinofuro[2,3‐b]quinoline derivatives were synthesized from dictamnine, a natural alkaloid, and evaluated for their cytotoxicity in the NCI's full panel of 60 human cancer cell lines derived from nine cancer cell types, including leukemia, non‐small‐cell lung cancer, colon cancer, CNS cancer, melanoma, ovarian cancer, renal cancer, prostate cancer, and breast cancer. 1‐[4‐(Furo[2,3‐b]quinolin‐4‐ylamino)phenyl]ethanone ( 5 ) (mean GI₅₀=0.025 μM ), bearing an 4‐acetylanilino substituent at C(4) of furo[2,3‐b]quinoline, was more active than its 3‐acetylanilino counterpart 7 (mean GI₅₀=5.27 μM ), and both clinically used anticancer drugs, N‐[4‐(acridin‐9‐ylamino)‐3‐methoxyphenyl]methanesulfonamide (m‐AMSA; mean GI₅₀=0.44 μM ) and daunomycin (mean GI₅₀=0.044 μM ). Compound 5 was capable of inhibiting all types of cancer cells tested with a mean GI₅₀ of less than 0.04 μM in each case except for the non‐small‐cell lung cancer (average GI₅₀=1.75 μM ). Although non‐small‐cell lung cancer is resistant to compound 5 , the sensitivity within this type of cancer cells varies: HOP‐62 (GI₅₀<0.01 μM ), NCI‐H460 (GI₅₀=0.01 μM ), and NCI‐H522 (GI₅₀<0.01 μM ) are very sensitive, while HOP‐92 (GI₅₀ = 12.4 μM ) is resistant. Among these non‐small‐cell lung cancers, NCI‐H522 was found to be very sensitive to 5, 8a , and 8b with a GI₅₀ values of <0.01, 0.074, and <0.01 μM , respectively.     

Synthesis and Cytotoxic Evaluation of Potential Bis‐Intercalators: Tetramethylenebis(oxy)‐ and Hexamethylenebis(oxy)‐Linked Assemblies Consisting of Flavone,Xanthone, Anthraquinone,and Dibenzofuran

In a search for potential inhibitors of solid‐tumor growth, certain alkanediylbis(oxy)‐linked assemblies were synthesized and evaluated for their cytotoxicity as bis‐intercalators. Symmetrical assemblies 1b – 12b were synthesized from their respective Aryl‐OH and either dibromobutane or dibromohexane, while unsymmetrical ones 13 – 15 were prepared from Aryl¹‐OH and either Aryl²‐O‐(CH₂)₄Br or Aryl²‐O‐(CH₂)₆Br. These bis‐intercalators were inactive against the growth of leukemia cells. However, some of them were active against the growth of certain solid tumors such as HOP‐62, HOP‐92 (non‐small‐cell lung cancer), SF‐265, SNB‐75, U251 (CNS cancer), A498 (renal cancer), and HS578T (breast cancer). Among them, [hexane‐1,6‐diylbis(oxy)bis(4,1‐phenylene)]bis[4H‐1‐benzopyran] ( 6b ) was especially active against the growth of all CNS cancer cell lines and also the growth of A498, HOP‐62, and HOP‐92 with GI₅₀ values of 17.0, 20.0, and 21.8 μM , respectively.     

Synthesis and Cytotoxic Activities of α‐Methylidene‐γ‐butyrolactones Bearing a Quinolin‐4(1H)‐one Moiety

The cytotoxicities of the α‐methylidene‐γ‐butyrolactones 4 , 5 , and 8 , which are linked to a quinolin‐4(1H)‐one moiety through a piperazine or O‐atom bridge were studied. These compounds were synthesized by alkylation of 1‐ethyl‐6‐fluoro‐1,4‐dihydro‐7‐hydroxy‐4‐oxoquinoline‐3‐carboxylic acid ( 6 ) followed by a Reformatsky‐type condensation. Compounds 4 , 5 , and 8 were evaluated in vitro against 60 human‐tumor cell lines derived from nine cancer‐cell types and demonstrated not only strong growth‐inhibitory activities against leukemia cancer cells, but also fairly good activities against the growth of certain solid tumors (see Table). The O‐bridged derivatives 8a and 8b exhibit both cytostatic (mean log GI₅₀=−5.20 and −5.82, resp.) and cytocidal (mean log LC₅₀=−4.30 and −4.93, resp.) effects, while the piperazine‐bridged analogues 4 and 5 possess only weak cytostatic (mean log GI₅₀=−5.19 and −4.74, resp.; mean log LC₅₀>−4.00) capability. Among them, 8b is the most potent, with log GI₅₀=−6.47, −6.72, −6.53, and −6.52 against leukemia, SW‐620 (colon), Lox IMV1, and SK‐MEL‐28 (melanoma) cancer cells, respectively.     

Ciprofloxacin/Gatifloxacin‐1,2,3‐triazole‐isatin Hybrids and Their In Vitro Anticancer Activity

Eleven novel ciprofloxacin/gatifloxacin‐1,2,3‐triazole‐isatin hybrids ( 8a – k ) were designed, synthesized, and screened for their in vitro anticancer activity in this paper. A significant part of the synthesized hybrids was active against A549, HepG2, and SF‐268 cancer cell lines, whereas the parent drugs ciprofloxacin and gatifloxacin were devoid of activity. Among them, hybrid 8i (IC₅₀: 78.1–90.7 μM) was found to be the most active against A549, HepG2, and SF‐268 cancer cell lines, and it was comparable with or better than Vorinostat (IC₅₀: 71.1 to >100 μM). Thus, these kind hybrids have potentiality for discovery of new anticancer candidates for clinical deployment in the control and eradication of cancers.     

Synthesis and Microtubule‐Destabilizing Activity of N‐Cyclopropyl‐4‐((3,4‐dihydroquinolin‐1(2H)‐yl)sulfonyl)benzamide and its Analogs

While clinically useful, microtubule‐targeting agents are limited by factors that include their susceptibility to multidrug resistance. A series of aryl sulfonamides, terminally substituted with an amide or carboxylic acid, was synthesized and assayed for biological activity in two human cancer cell lines. The resulting antiproliferative activity data demonstrated that an amide was superior to a carboxylic acid in the para position. The most potent compound ( 3 ) had an IC₅₀ for growth inhibition in the low micromolar range, caused cells to accumulate in G₂M of the cell cycle, and led to depolymerization of microtubules. It was also not susceptible to the P‐glycoprotein drug efflux pump that underpins the resistance of cells to long‐term drug treatment schedules.     

Synthesis,Crystal Structure and Anticancer Activities of Tetrahydropyrido[4,3‐d]dihydropyrimidine‐2‐thiones

A new series of tetrahydropyrido[4,3‐d]dihydropyrimidine‐2‐thiones ( 3a–3x ) were designed and synthesized. Their structures were confirmed by ¹H NMR, IR, MS and elemental analysis, and the conformation of compound 3j was confirmed by X‐ray diffraction. Preliminary bioassays indicated that most of the target compounds presented good antiproliferative activities against leukemic K562 cells, ovarian cancer HO‐8910 cells and liver cancer SMMC‐7721 cells in vitro. Among them the compounds 3i and 3m afford the best activity, the IC₅₀ of them were 3.22 and 3.65 µg/mL against leukemic K562 cells, respectively, which were lower than the anticancer drug of clinical practice 5‐FU (IC₅₀=8.56 µg/mL). Preliminary mechanism of action studies revealed that compound 3i caused DNA fragmentation and activated caspase‐3/7 in leukemic K562 cells.     

An efficient synthesis and cytotoxic activity of 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole obtained using a magnetically recyclable Fe3O4 nanocatalyst‐mediated white tea extract

A simple and efficient procedure has been developed for the synthesis of biologically relevant 2‐substituted benzimidazoles through a one‐pot condensation of o‐phenylenediamines with aryl aldehydes catalysed by iron oxide magnetic nanoparticles (Fe₃O₄ MNPs) in short reaction times with excellent yields. In the present study, Fe₃O₄ MNPs synthesized in a green manner using aqueous extract of white tea (Camelia sinensis) (Wt‐Fe₃O₄ MNPs) were applied as a magnetically separable heterogeneous nanocatalyst to synthesize 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole which has potential application in pharmacology and biological systems. Fourier transform infrared and NMR spectroscopies were used to characterize the 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole. In vitro cytotoxicity studies on MOLT‐4 cells showed a dose‐dependent toxicity with non‐toxic effect of 2‐(4‐chlorophenyl)‐1H–benzo[d]imidazole, up to a concentration of 0.147 µM. The green synthesized Wt‐Fe₃O₄ MNPs as recyclable nanocatalyst could be used for further research on the synthesis of therapeutic materials, particularly in nanomedicine, to assist in the treatment of cancer.     

Syntheses and antitumor activities of medium molecular weight polymers containing α-ethoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil

The new monomer, α-ethoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl-5-fluorouracil (EETFU), was synthesized from 5-fluorouracil (5-FU) and α-ethoxy-exo-3,6-epoxy-1,2,3,6-tetrahydrophthaloyl chloride. Its homopolymer and copolymers with acrylic acid (AA) and vinyl acetate (VAc) were synthesized by photopolymerizations using 2,2-dimethoxy-2-phenylaceto-phenone. The synthesized samples were characterized by FT-IR, ¹H-NMR and ¹³C-NMR spectroscopes, elemental analysis, and gel permeation chromatography. The EETFU contents in poly(EETFU-co-AA) and poly(EETFU-co-VAc) were 40 and 37 mol %, respectively. The number average molecular weights were in range from 8,400 to 10,300. The in vitro cytotoxicities of synthesized samples were evaluated against mouse mammary carcinoma (FM3A), mouse leukemia (P388), and human histiocytic lymphoma (U937) as cancer cell lines and mouse liver cells (AC2F) as a normal cell line. The range of IC₅₀ values obtained from the in vitro test for synthesized samples were 0.03–0.16 µg/mL against cancer cell lines. The in vitro cytotoxicities of polymers were beter than 5-FU. The in vivo antitumor activities of synthesized monomer and polymers were also investigated by mice bearing the sarcoma 180 tumor cells. The in vivo antitumor activities of the synthesized monomer and polymers were greater than those of 5-FU at corresponding dosage concentrations. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2619–2627, 1999     

Moxifloxacin/Gatifloxacin‐1,2,3‐triazole‐isatin Hybrids with Hydrogen‐Bond Donor and Their In Vitro Anticancer Activity

A series of novel moxifloxacin/gatifloxacin‐1,2,3‐triazole‐isatin hybrids ( 8a – i ) were designed, synthesized, and screened for their in vitro anticancer activity in this paper. All of the synthesized hybrids were active against A549 and HepG2 cancer cell lines, whereas the parent drugs moxifloxacin and gatifloxacin were devoid of activity. Among them, hybrid 8i (IC₅₀: 41.1–98.3 μM) showed considerable activity against A549, HepG2, and MCF‐7 cancer cell lines, and it was no inferior to Vorinostat (IC₅₀: 64.32 to >100 μM) against the three cancer cell lines. Thus, this kind of hybrids has potentiality for discovery of new anticancer candidates for clinical deployment in the control and eradication of cancers.     

Synthesis,structural and chemosensitivity studies of arene d6 metal complexes having N‐phenyl‐N´‐(pyridyl/pyrimidyl)thiourea derivatives

The d⁶ metal complexes of thiourea derivatives were synthesized to investigate its cytotoxicity. Treatment of various N‐phenyl‐N´ pyridyl/pyrimidyl thiourea ligands with half‐sandwich d⁶ metal precursors yielded a series of cationic complexes. Reactions of ligand (L1‐L3) with [(p‐cymene)RuCl₂]₂ and [Cp*MCl₂]₂ (M = Rh/Ir) led to the formation of a series of cationic complexes bearing general formula [(arene)M(L1)к²_(N,S)Cl]⁺, [(arene)M(L2)к²_(N,S)Cl]⁺ and [(arene)M(L3)к²_(N,S)Cl]⁺ [arene = p‐cymene, M = Ru ( 1 , 4 , 7 ); Cp*, M = Rh ( 2 , 5 , 8 ); Cp*, Ir ( 3 , 6 , 9 )]. These compounds were isolated as their chloride salts. X‐ray crystallographic studies of the complexes revealed the coordination of the ligands to the metal in a bidentate chelating N,S‐ manner. Further the cytotoxicity studies of the thiourea derivatives and its complexes evaluated against HCT‐116 (human colorectal cancer), MIA‐PaCa‐2 (human pancreatic cancer) and ARPE‐19 (non‐cancer retinal epithelium) cancer cell lines showed that the thiourea ligands displayed no activity. Upon complexation however, the metal compounds possesses cytotoxicity and whilst potency is less than cisplatin, several complexes exhibited greater selectivity for HCT‐116 or MIA‐PaCa‐2 cells compared to ARPE‐19 cells than cisplatin in vitro. Rhodium complexes of thiourea derivatives were found to be more potent as compared to ruthenium and iridium complexes.     

Lysosome‐targeted potent half‐sandwich iridium(III) α‐diimine antitumor complexes

Fifteen organometallic Ir(III) half‐sandwich complexes ( 1A – 5C ) having the general formula [(η⁵‐Cp^x)Ir(N^N)Cl]PF₆ (Cp^x = Cp*, tetramethyl(phenyl)cyclopentadienyl (Cp^xph) or tetramethyl(biphenyl)cyclopentadienyl (Cp^xbiph); N^N = diamine) have been synthesized and characterized. The molecular structure of 1A was determined using single‐crystal X‐ray diffraction analysis. The hydrolysis of 1A – 5C was monitored using UV–visible spectra. Complexes 3A – 3C showed catalytic activity for the oxidation of NADH to NAD⁺, where 3C showed the highest turnover number of 29.9 within 450 min. Cytotoxicity examination by MTT assay was carried out against two human cancer cell lines (HeLa and A549) after 24 or 48 h drug treatment. The complexes showed high potency, where the most potent complex ( 3C ; IC₅₀ = 3.4 μM) was six times more active than cisplatin against A549 cells after 24 h drug exposure. Cytotoxic potency towards A549 cells increased with phenyl substitution on Cp ring: Cp^xbiph > Cp^xph > Cp*. In addition, the biological studies showed that 3C caused cell apoptosis and cell cycle arrest at G₁ phase in A549 cancer cells. Moreover, 3C increased the level of reactive oxygen species markedly after 24 h, which may provide an important basis for killing cancer cells. Confocal laser scanning microscopy was used to track 3C in A549 cells. The cellular localization experiment showed that 3C targeted lysosomes and caused lysosomal damage.     

Synthesis and Cytotoxicity of Arene‐Ru Compounds Containing 4‐Nitroaniline or 2‐Halogenated 4‐Nitroaniline

The compounds [(η⁶‐p‐cymene)RuCl₂(4‐nitroaniline)] and [(η⁶‐p‐cymene)RuCl₂(2‐halogen‐4‐nitroaniline)] were synthesized and characterized by various means. The [(η⁶‐p‐cymene)RuCl₂(4‐nitroaniline)] and [(η⁶‐p‐cymene)RuCl₂(2‐fluoro‐4‐nitroaniline)] compounds were determined by X‐ray diffraction, appearing in a distorted piano‐stool type of arrangement with similar bond lengths and angles around the ruthenium. The compounds exhibited moderate to strong in vitro cytotoxicity against A549 and MCF‐7 human cancer cells. Substitution of heavy halogen atom on the ortho position of para‐nitroaniline weakened the cytotoxicity against both of MCF‐7 and A549, except the cases of fluorine substitution for hydrogen atom regarding A549 and bromine substitution for chlorine atom regarding MCF‐7, which showed minor deviation.     

Porous CuxCoyS Supraparticles for In Vivo Telomerase Imaging and Reactive Oxygen Species Generation

In this study, we successfully synthesized Cu_xCo_yS supraparticles (SPs) on the nanoscale featuring multiple pores inside and strong absorption from 400 to 900 nm. Porous Cu_xCo_yS SPs produced the highest reactive oxygen species (ROS) yield (1.39) when illuminated with near‐infrared (NIR) light. Furthermore, we demonstrated that Cu_xCo_yS SPs could be used to identify cancer cells through intracellular telomerase‐responsive fluorescence (FL) imaging in living cells. Because the Cu_xCo_yS SPs were associated with telomerase‐responsive bioimaging and high ROS production, they can be efficiently used in the diagnosis and therapy of tumors with high selectivity and excellent therapeutic effects in vivo. This study provides a new vision for the creation of multifunctional SPs, which can be used as cellular sensors and control tools for pathologies across a broad range of biological systems.     

Synthesis and Cytotoxicity Evaluation of Certain α‐Methylidene‐ γ‐butyrolactones Bearing Coumarin,Flavone, Xanthone,Carbazole, and Dibenzofuran Moieties

The cytotoxicities of α‐methylidene‐γ‐butyrolactones, which are linked to coumarins (see 15 and 16 ) and to potential DNA‐intercalating carriers such as flavones, xanthones, carbazole, and dibenzofuran (see 9a – e , 10a – e , 11 , and 12 ), were studied. These compounds were synthesized via alkylation of their hydroxy precursors followed by a Reformatsky‐type condensation (Scheme). These α‐methylidene‐γ‐butyralactones were evaluated in vitro against 60 human tumor cell lines derived from nine cancer cell types and demonstrated a strong growth‐inhibitory activity against leukemia cancer cells (Tables 1 and 2). For flavone‐ and xanthone‐containing α‐methylidene‐γ‐butyrolactones 9a – e and 10a – e , respectively, the overall potency (mean value) decreased on introduction of an electron‐withdrawing substituent at the γ‐phenyl substituent and increased with an electron‐donating substituent. Comparing the different chromophores established the following order of decreasing potency (log GI₅₀): dibenzofuran ( 12 , −6.17) > flavone ( 9a , −5.96) > carbazole ( 11 , −5.80) and xanthone ( 10a , −5.77) > coumarin ( 15 , −5.60; 16 , −5.65). Among them, the dibenzofuran derivative 12 showed not only strong inhibitory activities against leukemia cancer cell lines with an average log GI₅₀ value of −7.22, but also good inhibitory activities against colon, melanoma, and breast cancer cells with average log GI₅₀ values of −6.23, −6.31, and −6.39, respectively.     

Coordination‐Driven Self‐Assembly and Anticancer Potency Studies of Ruthenium–Cobalt‐Based Heterometallic Rectangles

Three new cobalt–ruthenium heterometallic molecular rectangles, 1 – 3 , were synthesized through the coordination‐driven self‐assembly of a new cobalt sandwich donor, (η⁵‐Cp)Co[C₄‐trans‐Ph₂(4‐Py)₂] (L ; Cp: cyclopentyl; Py: pyridine), and one of three dinuclear precursors, [(p‐cymene)₂Ru₂(OO∩OO)₂Cl₂] [OO∩OO: oxalato ( A₁ ), 5,8‐dioxido‐1,4‐naphthoquinone ( A₂ ), or 6,11‐dioxido‐5,12‐naphthacenedione ( A₃ )]. All of the self‐assembled architectures were isolated in very good yield (92–94 %) and were fully characterized by spectroscopic analysis; the molecular structures of 2 and 3 were determined by single‐crystal X‐ray diffraction analysis. The anticancer activities of bimetallic rectangles 1 – 3 were evaluated with a 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT) assay, an autophagy assay, and Western blotting. Rectangles 1 – 3 showed higher cytotoxicity than doxorubicin in AGS human gastric carcinoma cells. In addition, the autophagic activities and apoptotic cell death ratios were increased in AGS cells by treatment with 1 – 3 ; the rectangles induced autophagosome formation by promoting LC3‐I to LC3‐II conversion and apoptotic cell death by increasing caspase‐3/7 activity. Our results suggest that rectangles 1 – 3 induce gastric cancer cell death by modulating autophagy and apoptosis and that they have potential use as agents for the treatment of human gastric cancer.     

Synthesis,Characterization, and in vitro Cytotoxicity of Gold(I) Complexes of 2‐(Diphenylphosphanyl)ethylamine and Dithiocarbamates

Gold(I) complexes of 2‐(diphenylphosphanyl)ethylamine or (2‐aminoethyl)diphenylphosphine (AEP), and dithiocaarbamates (R₂NCS₂) were prepared by the reaction of these ligands with (CH₃)₂S‐AuCl in dichloromethane. The synthesized complexes [Au(AEP)Cl] ( 1 ), [Au(AEP)₂]Cl ( 2 ), and [Au₂(R₂NCS₂)₂]_n (R₂ = dimethyl ( 3 ), diethyl ( 4 ), and dibenzyl ( 5 )) were characterized by elemental analysis, IR, ¹H, ¹³C and ³¹P NMR spectroscopy. The complexes were evaluated for anticancer activity against three cancer cells, A549 (human lung carcinoma), HCT15 (human colon cancer), and MCF7 (human breast cancer) cell lines. Three of the five tested complexes showed significant in vitro cytotoxicity and for A549, the inhibition effect of three compounds is greater than cisplatin.     

An Efficient Synthesis of Chromeno[4,3‐d]isoxazolo[5,4‐b]pyridin‐6‐one Derivatives

A series of chromeno[4,3‐d]isoxazolo[5,4‐b]pyridin‐6‐one derivatives were easily and efficiently synthesized by the reaction of 3‐acyl‐2H‐chromen‐2‐ones with isoxazol‐5‐amine in acetic acid. Some synthesized compounds were evaluated for their antiproliferative properties in vitro against cancer cells, and these compounds were found to have some activities.     

Preparation of Ultrathin Two‐Dimensional TixTa1−xSyOz Nanosheets as Highly Efficient Photothermal Agents

Although two‐dimensional (2D) metal oxide/sulfide hybrid nanostructures have been synthesized, the facile preparation of ultrathin 2D nanosheets in high yield still remains a challenge. Herein, we report the first high‐yield preparation of solution‐processed ultrathin 2D metal oxide/sulfide hybrid nanosheets, that is, Ti_x Ta_1−x S_y O_z (x =0.71, 0.49, and 0.30), from Ti_x Ta_1−x S₂ precursors. The nanosheet exhibits strong absorbance in the near‐infrared region, giving a large extinction coefficient of 54.1 L g⁻¹ cm⁻¹ at 808 nm, and a high photothermal conversion efficiency of 39.2 %. After modification with lipoic acid‐conjugated polyethylene glycol, the nanosheet is a suitable photothermal agent for treatment of cancer cells under 808 nm laser irradiation. This work provides a facile and general method for the preparation of 2D metal oxide/sulfide hybrid nanosheets.